U.S. patent number 6,459,955 [Application Number 09/715,307] was granted by the patent office on 2002-10-01 for home cleaning robot.
This patent grant is currently assigned to The Procter & Gamble Company. Invention is credited to Eric Richard Bartsch, Charles William Fisher, Paul Amaat France, Gary Gordon Heaton, Thomas Charles Hortel, James Frederick Kirkpatrick, Arseni Velerevich Radomyselski, James Randy Stigall.
United States Patent |
6,459,955 |
Bartsch , et al. |
October 1, 2002 |
Home cleaning robot
Abstract
An autonomously movable cleaning robot comprising a platform and
motive force to autonomously move the robot on a substantially
horizontal surface having boundaries. The robot further has a
computer processing unit for storing, receiving and transmitting
data, and a cleaning implement operatively associated with the
robot. The robot receives input data from an external source. The
external source may be physical manipulation of the robot, remote
control, or by triangulation from at least three external
transmitters.
Inventors: |
Bartsch; Eric Richard
(Cincinnati, OH), Fisher; Charles William (Loveland, OH),
France; Paul Amaat (West Chester, OH), Kirkpatrick; James
Frederick (Milford, OH), Heaton; Gary Gordon
(Cincinnati, OH), Hortel; Thomas Charles (Cincinnati,
OH), Radomyselski; Arseni Velerevich (Hamilton, OH),
Stigall; James Randy (Hebron, KY) |
Assignee: |
The Procter & Gamble
Company (Cincinnati, OH)
|
Family
ID: |
22602381 |
Appl.
No.: |
09/715,307 |
Filed: |
November 17, 2000 |
Current U.S.
Class: |
700/245;
318/568.11; 342/418; 318/587; 318/568.16; 318/568.12; 342/457;
700/259; 700/258; 700/256; 700/247 |
Current CPC
Class: |
G05D
1/0253 (20130101); A47L 11/4061 (20130101); G05D
1/0221 (20130101); A47L 9/00 (20130101); F24F
11/30 (20180101); A47L 9/0009 (20130101); F24F
8/10 (20210101); A47L 9/009 (20130101); G05D
1/0272 (20130101); A47L 11/4011 (20130101); G05D
1/0274 (20130101); F24F 2110/50 (20180101); Y02B
30/70 (20130101); G05D 1/0227 (20130101); G05D
2201/0207 (20130101); G05D 2201/0203 (20130101); G05D
1/0242 (20130101); G05D 1/028 (20130101); A47L
2201/04 (20130101); F24F 8/50 (20210101); G05D
1/0246 (20130101); G05D 2201/0214 (20130101); F24F
2221/42 (20130101); G05D 1/0255 (20130101); G05D
1/0261 (20130101) |
Current International
Class: |
A47L
9/00 (20060101); G05D 1/02 (20060101); G06F
019/00 () |
Field of
Search: |
;700/245,247,256,259,79,83,258 ;318/587,568.11,568.16,568.12
;701/22,23,25,24,206,207,225,300,26,28,217,223 ;342/457,418
;180/167,169 ;340/990,991,995 ;215/319 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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3536974 |
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Apr 1987 |
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DE |
|
0476023 |
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Mar 1992 |
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EP |
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0786229 |
|
Jul 1997 |
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EP |
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2324047 |
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Apr 1977 |
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FR |
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99178764 |
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Jul 1999 |
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JP |
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99178765 |
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Jul 1999 |
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JP |
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WO9702075 |
|
Jan 1997 |
|
WO |
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WO01/06905 |
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Feb 2001 |
|
WO |
|
Other References
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cleaning task, 2001, IEEE, pp. 1041-1046.* .
Jung et al., Range adn pose estimation for visual servoing, 1998,
Internet/IEEE, pp. 1226-1229.* .
Science News, Computer designs and makes robots, 2000, Internet,
pp. 1-4.* .
Spencer, Personal robots, 1999, Internet, pp. 1-4.* .
Takahashi et al., Tension control of wire suspended mechanism and
application to bathroom cleanning robot, 2000, Internet, p
143-147.* .
M. Sekiguchi et al., "Behavior Control For A Mobile Robot By
Multi-Hierarchical Neural Network", Proceedings of the
International Conference on Robotics and Automation, Scottsdale,
May 15-19, 1989, vol. 3, May 15, 1989, pp. 1578-1583, XP000044339,
Institute of Electrical and Electronics Engineers. .
A. Holenstein et al., "Collision Avoidance In A Behavior-Based
Mobile Robot Design", Proceedings of the International Conference
on Robotics and Automation, Sacramento, Apr. 9-11, 1991, vol. 1,
No. Conf. 7, Apr. 9, 1991, pp. 898-903, XP000218429, Institute of
Electrical and Electronics Engineers. .
Fei Yue Wang et al., "A Petri-Net Coordination Model For An
Intelligent Mobile Robot", IEEE Transactions On Systems, Man And
Cybernetics, vol. 21, No. 4, Jul. 1, 1991, pp. 777-789,
XP000263601. .
R. Hinkel et al., "An Application For A Distributed Computer
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Radio Shack Product Catologue No. Dustbot 600-2556. 16 pictures of
the Radio Shack Dustbot are enclosed..
|
Primary Examiner: Cuchlinski, Jr.; William A.
Assistant Examiner: Marc; McDieunel
Attorney, Agent or Firm: Huston; Larry L. Lewis; Leonard
L.
Parent Case Text
This application claims benefit of provisional application No.
60/166,237 filed Nov. 18, 1999.
Claims
What is claimed is:
1. An autonomously, movable home cleaning robot comprising: a) a
platform; b) a motive force attached to said platform, said motive
force to autonomously move said platform on a substantially
horizontal surface having boundaries; c) a computer processing unit
for storing, receiving and transmitting data, said computer
processing unit attached to said platform; d) a cleaning implement
operatively associated with said platform; and e) a power source
connected to said motive force and said computer processing unit,
whereby said computer processing unit directs horizontal movement
of said platform within the boundaries of the horizontal surface
based upon input data defining said boundaries, said input data
being input to said robot by physical manipulation of said robot or
by remote control.
2. An autonomously, movable cleaning robot comprising: a) a
platform; b) a motive force attached to said platform, said motive
force to autonomously move said platform on a substantially
horizontal surface having boundaries; c) a computer processing unit
for storing, receiving and transmitting data, said computer
processing unit attached to said platform; d) at least one sensor
attached to said platform and capable of detecting an obstacle on
the horizontal surface, said sensor providing input to said
computer processing unit; e) a cleaning implement operatively
associated with said platform; and f) a power source connected to
said motive force and said computer processing unit, whereby said
computer processing unit directs horizontal movement of said
platform within the boundaries of the horizontal surface based upon
input data received by physical manipulation of said robot or by
remote control, wherein said input data are useful for manipulating
said robot through a desired task.
3. A home cleaning robot according to claim 2, wherein said sensor
interrupts said motion when said sensor senses an obstacle.
4. A autonomously, movable home cleaning robot comprising: a) a
platform; b) a motive force attached to said platform, said motive
force to autonomously move said platform on a substantially
horizontal surface having boundaries; c) a navigation system
including a computer processing unit for receiving, storing and
transmitting data, said navigation system receiving input about an
environment that includes the horizontal surface and using the
input to map said horizontal surface; d) a cleaning implement
operatively associated with said platform; and e) a power source
connected to said motive force and said navigation system, whereby
said navigation system directs the movements of said platform in
accordance with the map of said horizontal surface, said navigation
system comprising a triangulation system including three fixed
transmitters located within the environment, said computer
processing unit using signals received from said transmitters to
calculate a coordinate position of said robot within the boundaries
of the surface, and generating a control signal to steer said robot
in the direction of the next point of said stored coordinate
system.
5. A home cleaning robot according to claim 4, wherein said
navigation system includes a receiver for receiving input from the
environment, said receiver sending input to said computer
processing unit, whereby said computer processing unit using the
input to map the horizontal surface.
6. A home cleaning robot according to claim 5, wherein said
navigation system including a visual image processor and a camera
attached to said robot, said system determining said robot's
orientation and position on the surface based upon an image of a
ceiling above the surface, said system then generates control
signals to steer said robot within the boundaries of the
surface.
7. A home cleaning robot according to claim 5, wherein said
navigation system includes a position identification apparatus that
senses a distance traveled by said robot and a change in a
direction of travel of said robot, said navigation system
calculates a position of said robot in two-dimensional coordinates
in response to the sensed distance and the sensed change in
direction, and generates a position signal representative of said
robot position.
8. A home cleaning robot according to claims 1, 3 or 5, further
comprising a cover removably attached to said platform.
9. A home cleaning robot according to claims 1, 3 or 5, further
comprising a ball support.
Description
FIELD OF THE INVENTION
The present invention is directed to autonomous, microprocessor
controlled home cleaning robots having useful functions. More
specifically, the present invention relates to autonomous, mobile
home cleaning robots having a low energy cleaning apparatus. Even
more specifically, the present invention relates to autonomous,
mobile home cleaning robots having a low energy cleaning apparatus
and a capability of adaptively performing and being trained to
perform useful chores.
BACKGROUND OF THE INVENTION
Toys have provided play value and entertainment to children when
the child imagines the toys are capable of independent behavior.
Microprocessor controlled toys have recently offered limited
simulations of living behavior for the non-productive enjoyment of
children including violence-oriented video games. Microprocessor
based toys, until now, do not educate by engaging in useful
task-oriented behaviors with the child. Ideally a toy should
benefit the child by not only providing play value, but also
transparently encourage creative, task-oriented behavior which
benefits the child and reduces the workload of working families.
This invention is directed toward that end.
Principles of toys can be adapted to useful home cleaning robots. A
toy that serves that purpose would be capable of performing useful
tasks, capable of easily being trained by the child to perform
tasks, and would be adaptive in operation to account for less then
ideal training. Further the toy should have the appearance of some
real or imaginary thing consistent with the useful behavior the
child and toy would be engaged in so that the child's interaction
is with an emotionally engaging plaything. Once learned, the
task-oriented behavior should be storable, transferable, and
recallable.
Non-functional toys intended to encourage task-oriented behavior in
children have traditionally approximated tools and appliances used
to perform tasks. For example, U.S. Pat. No. 5,919,078 (Cassidy,
issued Jul. 6, 1999) discloses a toy which has the appearance of a
cyclone-type vacuum cleaner. However, it does not vacuum, learn, or
adapt.
Toys are also known to the art, which while they do not perform
useful functions, do have some level of behavioral response to
their environment. Recent examples of such toys are "Electronic
Furby" available from Tiger Electronics, Vernon Hills, Ill. and
various "Actimates" interactive dolls from Microsoft Corp., Redmond
Wash. These toys are not suitable for teaching children to perform
useful tasks although some of the better toys may build
intellectual skills in reading, writing, or math. They do not learn
tasks nor are they substantially adaptive to their environment.
Toys are also known to the art which are programmable by some means
but which do not respond to environmental changes. For example U.S.
Pat. No. 4,702,718 (Yanase, issued Oct. 27, 1987) discloses a
mobile toy wherein the toy responds optically to prerecorded,
rotating disks.
Toys are known which are mobile and to a limited degree have some
means to perform a useful function but which are not trainable or
adaptive. An example is a Dustbot toy previously sold by Radio
Shack/Tandy Corporation, Fort Worth, Tex., catalog number 60-2556
which was a motorized, mobile toy capable of lightly vacuuming
crumbs from a table-top. The toy was not trainable or adaptive.
Expensive consumer robots primarily intended for entertainment are
known. A recent example is a robotic entertainment dog called
"Aibo" available briefly from the Sony Corporation at a cost two
orders of magnitude beyond most toys. Various devices of this type
including commercially available research robots have been promoted
as home robots for many years without widespread commercial
success. Typically they require complex user interactions including
programming, are not designed to perform useful tasks and are too
costly to serve as children's toys as opposed to prestigious adult
entertainment devices.
Many industrial and military "robots" exist which are trainable or
adaptively interact with their environment or both. This robotic
art is not directed at toys or the home. It focuses exclusively on
utility without regard to play value. U.S. Pat. No. 3,952,361
(Wilkins, issued Apr. 27, 1976) discloses the general principle of
task training in a self-guided floor cleaner which is manually
operated through a floor-cleaning task. The device is trained by
recording pulse-driven wheel motor signals during the manual
operation onto a tape recorder. The tape subsequently is played to
generate motor-driving pulses for automated operation.
Other "training" means used in mobile commercial robots include
making a digital image map of the ceiling during manual operation
from an upward-focused, robot-mounted video camera as in U.S. Pat.
No. 5,155,684 (Burke et al. Issued Oct. 13, 1992) which is hereby
incorporated by reference; setting up external beacons for
triangulation as in U.S. Pat. No. 5,974,347 (Nelson, issued Oct.
26, 1999) which is hereby incorporated by reference; or using
combinations of directional cues present in the operating
environment such as gravity, the earth's magnetic field (multi-axis
magnetometers), inertial guidance systems, global positioning via
satellite (GPS), and radar imaging as in the case of guided
missiles. Examples of such missile guidance technologies include
U.S. Pat. No. 5,451,014 (Dare et al. issued Sep. 19, 1995)
disclosing an inertial guidance system not requiring
initialization; U.S. Pat. No. 5,943,009 (Abbot, Aug. 24, 1999)
disclosing a simple GPS guidance system; and U.S. Pat. No.
5,917,442 (Manoongian et al., issued Jun. 29, 1999) disclosing
guidance means where the target is illuminated (by radar). Related
in technology, but not purpose, is U.S. Pat. No. 5,883,861 (Moser
et al., issued May 12, 1998) disclosing an electronic compass in a
wristwatch. Although many of these guidance technologies have been
reduced to compact solid-state devices, they have not, sans
warheads, heretofore been adapted for use in educational toys.
There is an unfilled for home cleaning robots that use low energy
cleaning techniques and thus make chores easier for the user.
SUMMARY OF THE INVENTION
The present invention relates to autonomous, mobile,
microprocessor-controlled home cleaning robots provided with the
means to perform useful functions and capable of learning and
adaptively performing useful functions.
In one embodiment, the present invention is a mobile,
microprocessor-controlled home cleaning robot. The robot comprises
a platform, a motive force attached to the platform. This motive
force moves the platform on a substantially horizontal surface. The
robot also includes a computer processing unit capable of storing,
receiving and transmitting data that is attached to said platform.
The robot also includes at least one sensor attached to the
platform, which is capable of detecting a change on the horizontal
surface. The sensor provides input to the computer processing unit.
The platform includes a cleaning implement operatively associated
with the platform and a power source connected to the motive force
and computer processing unit, whereby the computer processing unit
directs horizontal movement of the platform based upon input data
received from the at least one sensor.
In one embodiment the present invention is comprised of an
autonomous, adaptive mobile home cleaning robot provided with a
detachable or dischargeable electrostatic cleaning cloth.
In one embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a detachable or dischargeable electrostatic cleaning
cloth.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of the platform of
the robot of the present invention;
FIG. 2 is a side elevational view of the platform shown in FIG.
1;
FIG. 3 is a side elevational view of one embodiment of a cover for
the platform, wherein the cover is designed to look like a
turtle;
FIG. 4 is a top planar view of a further embodiment of a cover for
the platform, wherein the cover is designed to look like a
mouse;
FIG. 5 is a block diagram of one embodiment of a robot control
system of the present invention;
FIG. 6 is a schematic plan view of an alternative robot platform
and control system in accordance with the present invention;
FIG. 7 is a diagram explanatory of a deviation of the robot from a
predetermined straight path in accordance with the control system
of FIG. 6.
FIG. 8a is an illustrative block diagram showing a mobile robot,
constructed and operated in accordance with one embodiment of the
invention, which includes a camera having an upwardly pointing
field of view for viewing a ceiling above the robot, the ceiling
having a plurality of ceiling fixture light sources;
FIG. 8b is a block diagram of the image processor 118 of FIG.
8a;
FIG. 8C is a block diagram which illustrates a feedback control
system wherein ceiling related position measurements function as an
error signal;
FIGS. 9a and 9b illustrate an image plane of the ceiling vision
system of FIG. 8a;
FIGS. 10a, 10b and 10c are illustrative views of the control system
in FIG. 8a within an environment having a plurality of ceiling
fixtures;
FIGS. 11a, 11b, 11c, 11d, 11e and 11f are graphical representations
of the mathematical derivation of robot position relative to
ceiling light fixtures;
FIG. 12 is a perspective view of a robot having a triangulation
control system;
FIG. 13 shows a perspective view of the rotating directional loop
antenna;
FIG. 14A shows a diagram of two circle equations together showing
the intersection which provides the x-y coordinates defining the
location of the robot using the triangulation control system in
FIG. 12;
FIG. 14B shows a diagram of one circle defined by the angle A and
the chord between transmitters T1 and T2, with the offset a and
radius r1;
FIG. 14C shows a diagram of another circle defined by the angle B
and the chord between transmitters T2 and T3, with the offsets b,
c, and radius r2;
FIG. 15 shows a functional block diagram of that part of the
control system of FIG. 12 located on the robot along with three
continuous wave transmitters;
FIG. 16 shows the functional blocks associated with signal
detection and pulse generation of the system in FIG. 12; and
FIG. 17 is a schematic diagram of the sequencer of the control
system in FIG. 12.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the word "autonomous" is meant to describe the
characteristic of independent mobility as opposed to active
guidance by a human. For example a radio-controlled home cleaning
robot relying on human operation of the remote control would not be
autonomous. A similar home cleaning robot being instantly navigated
by an onboard or off-board microprocessor and sensors without
immediate human guidance would be autonomous.
As used herein the word "learning" is meant to describe mapping by
being guided through a desired path or task manually and
electronically recording the motions made to follow the path or
perform the task. This may also be referred to as "training" the
home cleaning robot. The recording can be of encoders on motors or
wheels, recording an environment map of images or sonar responses,
images, or various forms of beacons such as radio frequency
sources, or passive RF beacons, or reflective or active optical
beacons. Other mapping means can be used such as off board imaging
or sensing of the mobile home cleaning robot in its environment
while being guided. Learning in this sense can be accomplished by
physically manipulating the home cleaning robot or by remotely
controlling the home cleaning robot through a desired task, or by
reinforcing desired behaviors as they occur by any communicative
means. Programming such as the writing of non-variant software is
not "learning" in the instant sense.
As used herein the word "adaptive" refers to storage of prior
actions with respect to a desired goal or endpoint and changing the
map of desired motor actions to optimize various behavior goals.
For example, if a goal is to avoid light, and traveling along a
first path does not reduce the level of incident light, that action
would not be repeated but others would be tried successively until
a direction or motion was found that resulted in reduced levels of
light. In other words the behavior to a stimuli is not fixed, but
varied until the desired goal is substantially achieved. Similar
adaptive behaviors include, but are not limited to, tactile or
sonar detection of obstacles that are discovered after programming
and selecting actions which result in planning a path around the
obstacle. It is to be understood that adaptive behavior is not
limited to path selection but may also be applied to other output
parameters such as light projection, audio output, speech patterns,
and so on--dynamic selection of a behavior in accordance with the
environment as found.
The primary emphasis of the instant invention is to provide an
automated home cleaning robot having a low energy-cleaning device,
which will free the user from such tasks. The present invention may
optionally have play value which can be achieved through the
inclusion of the inclusion of a personality by animalistic
appearance, actions, sound, and the like distinguishes the instant
invention from non-toys.
As used herein the phrase "play value" refers to the quality of
home cleaning robots that provides pleasure, recreation, and
training for user. One optional aspect of the instant invention is
that it could provide play value to children (of all ages) while
learning to perform useful tasks and teaching and watching their
toys perform such tasks.
As used herein the word "platform" refers to an electromechanical
device under microprocessor or computer control capable of some
physical action such as, but not limited to, motion including but
not limited to movement across a surface such as a horizontal
surface, heating, spraying, moving air in response to sensor inputs
such as sensed light, odor, contact, sound, radar, magnetic fields,
electromagnetic fields, moisture, and the like. Typically a
platform will be comprised of a microprocessor, a locomotion means,
sensors, and a power source. A platform may be embodied in a single
physical device or be distributed. For example a mobile platform
may be guided by a remote computer or by wireless Internet access
means to a remote computer. A data storage means may be on-board
the mobile home cleaning robot or at a remote sight.
The general design principles of robot platforms are well known and
described in the prior art. For applications, which require
movement on a relatively flat, horizontal surface, the most
suitable platform for the present invention is a wheeled or tracked
locomotion form where the wheels may be selectively driven. The
wheel or track alignment is substantially parallel. In two-wheeled,
as opposed to tracked, platforms, one or more additional castered
wheels or sphere-in-sockets may be used to support the body in
addition to the independent drive wheels. A track-driven platform
may be entirely supported by the tracks such as in the case of a
bulldozer. Wheeled robotic platforms are available from
Cybermotion, Salem, Va.; IS Robotics, Somerville, Mass.; Poulan,
Robotic Solar Mower Dept., Shreveport, La.; and Nomadic
Technologies Mountain View, Calif.
The robot of the present invention is "autonomously movable".
"Autonomously movable", as used herein, is illustratively defined
as the robot can move or translate within, preferably throughout,
boundaries of a substantially horizontal surface that is desired to
be cleaned without input from the user. "Movable", as used herein,
means the movement or translation of the entire robot body, or in
other words, the robot does not have a fixed base. The robot body
can translate and optionally can rotate. In contrast, a robot that
has a fixed base that rotates to accomplish tasks, such as sweep an
arm of the robot, is not included within the meaning of the present
invention.
The Home cleaning robot of the present invention is typically less
than 10 kilograms, preferably less than 8 kilograms.
FIG. 1 illustrates one embodiment of the platform of the present
invention provided with motor-driven wheels. The drive wheels 2,
are separately and independently driven by an encoder-equipped
motor 1 mounted on a common circuit board printed onto the
platform, 10. The platform is provided with fastening points 3, for
attachment of the cover by a fastening means not illustrated.
Sensors 4 and 6, the power cell 5, and microprocessor control unit
9 are likewise mounted on the platform printed circuit board. In an
alternative embodiment, a sound producing means 7, and an infrared
port 8, for download or uploading instructions and remote operation
of the platform is provided. It should be noted that tracks rather
than wheels could be used when the application involves locomotion
on other than a relatively smooth surface.
FIG. 2 is a side view of the platform showing a front-mounted
contact sensor 4, the printed circuit board 11 mounted on the
platform structure, and a ball support means 12.
FIGS. 3 and 4 illustrate typical covers that might be applied to
the platform to provide an animalistic appearance. FIG. 3
illustrates a turtle shell cover, and FIG. 4 illustrates an
animalistic cover, which may be fabricated from an electrostatic
dusting material. The covers typically will extend beyond the
wheels unless otherwise noted so that the wheels cannot be caught
on vertical obstacles.
Other means of locomotion may be used without changing the scope of
this invention. It is to be understood that a wheeled or tracked
platform is to be applied to tasks that are to be performed on
substantially level, horizontal surfaces such as floors, counter
tops, lawns, gardens, roofs with low angles of inclination, and the
like. The wheeled or tracked platform provides a motive force to
move the platform on a substantially horizontal surface.
Generally, the robot is placed onto a substantially horizontal
surface that is desired to be cleaned and then is powered on. Next,
the robot moves randomly about the substantially horizontal surface
performing a useful chore, such as cleaning with a nonwoven
electrostatic cloth. Upon coming in contact with either a
horizontal or vertical obstacle, the at least one sensor will
trigger the platform to stop motion and then reorient itself and
proceed with its task. This random motion robot does not include or
require a navigation system.
As used herein the word "map" or "mapping" refers to a data
structure stored in a computer memory means such as read and write
memory, magnetic media, optical media, or the like which represents
a task environment. This data may include but is not limited to a
stored schedule of actions such as the number of encoder pulses per
unit time from each of the locomotion motors, the compass direction
per unit time, or relative position coordinates (e. g. triangulated
position from sonar, light, or other beacon means, and other stored
or calculated data against which real time sensor inputs can be
compared to guide a mobile, computer operated platform or task
performing components thereof such as manipulators, projectors,
dispensing means, spray pumps, and so on. The map typically is
initially built by a user manually leading the home cleaning robot
through a set of desired actions or motions or the user doing so be
remote direction. More data may be added adaptively during
operation such as when obstacles are encountered. In a simple
example a platform with two drive wheels may be manually pushed
along a desired path. The output of optical, magnetic, or
mechanical encoders on each drive wheel, a series of pulses, are
recorded as a count per unit time for each encoder and stored in a
memory means by the microprocessor under program control. The data
storage means may be onboard the mobile home cleaning robot or
located remotely via a wireless communications link or the Internet
or some combination thereof.
One example of the microprocessor-based control and mapping system
suitable for the guidance system of the present invention is shown
and described in expired U.S. Pat. No. 4,674,048 (Okumura, issued
Jun. 16, 1987), which is herein incorporated by reference. The
guidance system comprises position identification means for sensing
a distance traveled by the robot and a change in a direction of
travel of the robot, calculating a position of the robot in
two-dimensional coordinates in response to the sensed distance and
the sensed change in direction, and generating a position signal
representative of the robot position. Such a guidance system is
known in the art. Obstruction sensor means senses an obstruction to
generate an obstruction signal. The obstruction sensor means are
mounted on a front end and both sides of the robot with respect to
an intended direction of travel of the robot. Storage means stores
a map consisting of a number of unit blocks, which are defined by
parallel columns and parallel rows in the two-dimensional
coordinates. Teaching means causes the robot to make a round along
a boundary of a range to be traveled by the robot, so that the
range is stored in the map of the storage means in response to the
position signal output from the position identification means.
Referring to FIG. 5 of the drawing, a distance sensor 20 for
producing a pulse signal which is proportional to a distance
traveled by the mobile robot, e.g. number of rotations of drive
wheels. A direction sensor 22, such as a gas rate gyro, is
sensitive to a change in the traveling direction of the robot. The
pulse signal output from the distance sensor 20 and the output of
the direction sensor are supplied to position identification means
24. The position identification means 24 is constructed to measure
a distance traveled by the robot by counting incoming pulses from
the distance sensor 20 and to identify a moving direction of the
robot from the output of the direction sensor 22, thereby
identifying by operation instantaneous positions of the robot in
two-dimensional coordinates for each unit travel distance.
Obstruction sensors 26 are mounted on the front, opposite sides and
back of the robot with respect to a direction of movement of the
robot. Each of the obstruction sensors 26 is adapted to sense a
wall, column or like obstruction and a distance to the obstruction
by emitting a supersonic wave and receiving the reflection. Also
mounted on the robot are touch sensors 4 which locate obstructions
by mechanical contact therewith, independently of the obstruction
sensors 26. The outputs of the sensors 4 and 26 are routed via an
amplifier 28 and an input/output (I/O) port 29D to a control
circuit 9, which comprises a microprocessor. Also, the output of
the position identification means 24 is applied to the control
circuit 9 via an I/O port 29A.
The control circuit 9 comprises a central operational circuitry
(CPU) 30, and a storage 32 made up of a read only memory (ROM) and
a random access memory (RAM). The control circuit 9 further
comprises an oscillator 34A for generating clock pulses, and an
interrupt controller 34B. As will be described, the CPU 30 delivers
a drive signal to a drive circuit 36 via an I/O port 29C in order
to reversibly control the rotation of drive motors (servo motors or
stepping motors) 1A and 1B, which are respectively associated with
right and left drive wheels of the robot. At the same time, the
control 9 may optionally control the rotation of an optional drive
motor 36 for cleaning sweepers, which are mounted on the robot. A
control console 38 is accessible for selectively turning on and off
a system power source, switching a running mode, setting a start
position, adjusting a sensitivity of the direction sensor 22, etc.
In order to teach the robot a boundary of a travel range assigned
thereto, a command may be applied to the drive 36 by interruption
with priority on a radio control basis. This is effected by a
remote control transmit unit 40 and a receive unit 42. The outputs
of the control console 38 and remote control receive unit 42 are
routed also to the control circuit 9 via an I/O port 29B.
Referring to FIG. 6, one particular embodiment of the mobile robot
is shown in a schematic plan view. As shown, the robot comprises a
platform 10 which is substantially entirely surrounded by a front
bumper 50, side bumpers 51 and 52, and a rear bumper 53, each
carrying the touch sensor 4 therewith. An obstruction is sensed by
the contact of any one of the bumpers 50-53 therewith.
As shown in FIG. 7, assume that the robot is deviated to the right
from the reference path by a distance "d" with respect to the
travelling direction of the robot, and that it is misoriented by an
angle .THETA. relative to the reference path. Then, that the
deviation of the robot is to the right of the reference path is
determined. Also, whether the sign of d+tan .THETA. is positive or
negative is determined by operation. Let it be assumed that d+tan
.THETA. is either d+tan .THETA..gtoreq.0 or d+tan
.THETA.+<0.
In the first-mentioned condition, d+tan .THETA..gtoreq.0, the
distance d is large, or the angle .THETA. is relatively small, or
the orientation of the robot lies in the positive angular range.
Then, the rotation speed V of the left drive wheel is controlled to
be V=V.sub.0 -(d+tan .THETA.) (where the minimum value of V is
assumed to be V.sub.0), while the rotation speed of the right drive
wheel is kept at V.sub.0, whereby the robot is caused to make a
leftward turn or rotate leftwardly about an axis thereof.
The other condition, d+tan .THETA.<0 represents a situation in
which the angle .theta. is negative and the robot is directed
toward the path at a large angle. In this case, while the rotation
of the left drive wheel is maintained the same, the rotation speed
V of the right drive wheel is controlled to be V=V.sub.0 +(d+tan
.THETA..), thereby turning or rotating the robot to the right.
In this manner, the actual path of the robot is controlled to the
reference path if dislocated therefrom, that is, the position of
the robot is corrected.
The compensation effected for rightward deviation of the actual
robot path from the reference path as described similarly applied
to leftward deviation of the robot, except for the reversal of
angles and that of the control over the right and left drive
wheels.
Due to the use of a tan function as a compensation term for the
angle .THETA., so long as MAX in the relation -MAX<tan
.THETA.<MAX is sufficiently large, there exists a position and
an angle where d+tan .THETA.=0 holds, even if the deviation d from
the path is substantial. At such a specific point, the right and
left drive wheels of the robot are equal in velocity and they
approach the path at an angle to the path which becomes closer to
the right angle as the distance d increases and decreases with the
decrease in the distance d. Stated another way, the orientation of
the robot is compensated sharply when the distance d is large and
the compensation is slowed down as the distance d becomes smaller.
This insures smooth compensation. If desired, the term d may be
multiplied by a positive constant ".alpha." and the term tan
.THETA. by a positive constant .beta. so that any desired path
compensation characteristic is established up to the point where
.alpha.d+.beta.tan .THETA.=0 holds, that is, the point where the
robot advances straight with the right and left drive wheels
running at an equal angle.
Teaching the robot a desired range of movement may be implemented
by the supersonic wave sensors 4A, 4B and 4C and the touch sensors
5 which are mounted on the robot itself, instead of the remote
control transmit and receive units. Some of the supersonic wave
sensors 4A, 4B and 4C are capable of identifying short and medium
ranges and the others, long ranges. Such self-teaching with the
various sensors is optimum for cleaning, for example, the floor of
a room which is surrounded by walls; the robot will make one round
automatically along the walls of the room by sensing the walls with
the sensors.
Another example of mapping suitable for use as a navigation system
in the present invention includes mapping via imaging ceiling
lights, which is known in the art. Such a system is shown and
described in expired U.S. Pat. No. 4,933,864 (Evans et al., issued
Jun. 12, 1990) and is herein incorporated by reference.
In such a mapping and navigation system, the robot microprocessor
uses an imaged input to make a map of an environment, such as a
kitchen, and determines the home cleaning robots position and
orientation on that map from an image input, such as the ceiling
lights in that room. In particular, the guidance system robot
images light patterns on the ceiling. By extension, the camera
could include the robot on a two dimensional surface.
Referring now to FIG. 8a there is shown a side view of one
embodiment of a mobile robot 110 comprising an electronic imaging
device, such as a camera 112. In accordance with the invention this
optical configuration is arranged to view a ceiling 114 having a
plurality of light fixtures 116, the ceiling 114 being disposed
above the desired path of the robot 110. The camera 112 preferably
includes a CCD imaging device having a square or rectangular field
of view (FOV) which is directed obliquely upward such that it
images the ceiling 114 within the forward path of the robot 110.
The camera 112 generates a plurality of pixels, individual ones of
which have a value indicative of an intensity of radiation incident
upon a corresponding surface area of the camera radiation sensing
device. Robot 110 further comprises an image processor 118 which is
coupled to the output of camera 112. Image processor 118, as shown
in greater detail in FIG. 8b, comprises a video memory 118A which
stores a representation of one video frame output of camera 112. An
input to video memory 118A may be provided by an analog to digital
(A/D) converter 118B which digitizes the analog output of camera
112. The digital output of A/D 118B may form an address input to a
lookup table (LUT) 118C wherein pixel brightness values may be
reassigned. The LUT 118C may also be employed for image
thresholding and/or histogram correction. Image processor 118
further comprises an image processing device, such as a
microcomputer 118D, which is coupled to the video memory 118A and
which is operable for reading the stored video frame data
therefrom. Image processor 118 further comprises memory 118E which
includes memory for storing program instructions, constants and
temporary data. The program data may be operable for performing
calculations of the type which will be described in detail
hereinafter. An output of image processor 118 which is expressive
of position information relating to ceiling fixtures 116 within the
FOV of camera 112 may be supplied, via an RS-232 or parallel data
link, to a navigation control processor 120 which derives
navigation data based upon the perceived image of the ceiling
environment, particularly the orientation of ceiling light
fixtures. This data may be employed to steer the robot down a
hallway or to orient the robot within a coordinate system of a room
or other enclosure having ceiling light fixtures. An output of
navigation control processor 120 is supplied to a drive and
steering control 122 which has outputs coupled to drive and
steering wheels 124. The wheels 124 are in contact with a
supporting surface 126 which is typically a floor. Navigation
control processor 120 typically receives an output from the drive
and steering control 122, the output being expressive of odometer
readings which relate to the distance traveled by the robot 110.
Navigation control processor 120 comprises a data processing device
having associated memory and support circuitry. An enclosure is
provided to contain the aforementioned apparatus and to provide
protection therefore.
As can be seen in FIG. 8c the navigation control processor 120 is
generally responsible for interpreting robot 110 position
measurements generated by ceiling navigation image processor 118,
in conjunction with possible inputs from other sensor systems, to
control the drive system 122 in order to guide the robot 110 along
a desired path. Thus, position measurements function as an error
signal in a feedback control system wherein the drive and steering
mechanisms serve as the actuators which change the position of the
robot.
The camera 112 may be a model TM440 CCD camera manufactured by
Pulnix. The camera 112 may have a relatively short focal length of,
for example, 8.5 mm in order to maximize the field of view.
Microcomputer 118D may be a member of the 68000 family of
microprocessor devices manufactured by Motorola, Inc. LUT 118C and
video memory 118A may be contained within a frame grabber pc-board
such as a type manufactured by Coreco or Imaging Technologies.
Referring briefly to FIG. 10a there is illustrated a typical
institutional hallway. In a suitably thresholded camera image
ceiling lights 116 are the overwhelmingly prominent visual
features. The linear edges, or straight line boundaries, of the
ceiling lights define, in accordance with the method and apparatus
of the invention, reference lines for visual navigation.
As can be appreciated, when searching for and identifying the
centers and edges of ceiling lights it is important to examine as
few pixels as possible in order to reduce overall processing time.
This search operation is facilitated by providing for an image
threshold or a camera 112 aperture setting which causes the ceiling
lights to appear as bright regions which are embedded within a dark
background. A binary threshold technique may then be utilized to
identify bright, illuminated pixels from dark pixels.
To initially locate a ceiling light in the image an initial
preliminary search may be performed over the entire image,
beginning at the top row of pixels and working towards the bottom
row. Once a pixel is detected that has a value above a
predetermined search threshold value the preliminary search is
terminated. The predetermined threshold value is influenced by such
factors as the type of camera employed, the camera aperture setting
and/or the particular type of pixel thresholding. The preliminary
search is preferably begun from the top of the image such that a
ceiling light that is nearest to the robot will first be
detected.
When a pixel above the threshold is detected a method of the
invention, as described below, may thereafter employ a binary
subdivision search. As an example; given a white point or pixel
within a ceiling light there is next located an edge of the light
where a transition from white to black occurs. This may be
accomplished by moving outwards from the white point while
examining pixel values to detect a transition from a pixel value
which corresponds to that of the light to a pixel value which
corresponds to the dark background. Of course, the pixel values may
not normally correspond to fully white or fully black but will
typically be expressed as varying shades of gray. Sampling every
pixel while moving towards an edge of the light may be less than
optimum in that the edge may be hundreds of pixels removed from the
initially detected pixel. Therefore, a preferred method involves
stepping initially by some relatively large increment of pixels,
such as by 16 pixels per step. Stepping outward in 16 pixel
increments continues until a pixel value indicates that the search
has entered the dark background. At this time the search increment
is divided by two and the search direction is reversed. This
process of dividing the stepping increment and reversing the
stepping direction continues until the step size is divided down to
one. At that point the pixel under consideration is either one
pixel into the bright light or one pixel into the dark background.
This search technique is repeated, as described below, to detect
multiple edges of a ceiling light in order to obtain sufficient
information to accurately locate the left and the right edges and a
center point of the light.
Referring to FIG. 11f it can be seen that after a pixel, designated
by the point (X), within a light is found a vertical line (1) and a
horizontal line (2) are projected through the point (X) to the
edges of the light using the above described pixel search method.
If the vertical line (1) is longer than the horizontal, a new
horizontal line (3) is projected from the center of line (1).
Instead, if the horizontal line (2) is longer a second vertical
line is projected from the center of the horizontal line (2). These
steps succeed in bringing the initial point, which may have been at
an extreme edge of the light, farther into the center of the light
as indicated by the point X'. Thereafter, the slope of the edges of
the light is determined as described below.
A plurality of vertical lines (4, 5, and 6) are projected, one line
(5) at the middle of the horizontal line (3) and the other two
lines (4,6) approximately 25% in from the ends of the horizontal
line (3). Thereafter, from the points (a, b, c, d, e, f) which
define the ends of the vertical lines (4,5,6) there is found an
average slope for the light. A line (7) is then projected which
passes through the center of vertical line (5), the line (7) having
a slope equal to the average slope of the light as previously
calculated. It should be noted that the vertical lines (4, 5, 6)
may have been drawn so close together that the calculated average
slope may not be of high accuracy. Thus, the line (7) may not
intersect the two ends of the light. Therefore, at points
approximately 25% of the way in from the ends of line (7) two
additional vertical lines (8,9) are projected and the average slope
from the end points (g, h, i, j) of lines (8,9) is determined. From
the center point of each of the two vertical lines (8,9) a line (10
and 11, respectively) is projected toward the nearest edge of the
light along the most recently computed average slope. The edge
transition between illuminated and nonilluminated pixels sensed
along lines 10 and 11 indicate the true ends of the light (A,B). At
a point halfway between the edges (A,B) is the center point of the
light (CP).
After accurately locating one light a second light is found and
analyzed in a substantially identical manner in order to generate a
set of points with which to project lines (C,D) to the vanishing
point at the horizon.
To find the second light a line (12) is projected downwards in the
image from the center (CP) of the first light and perpendicular to
the slope of line (7). Pixels along the line (12) are analyzed to
determine if another light is encountered. Because of the differing
angles which the lights may assume relative to one another line
(12) may not intersect a second light. If this is the case two more
lines (13,14) are projected from the ends of the first light
perpendicularly to the line (7) to determine where and if a second
light is intersected. From lines (12,13,14) it is assured that one
of them will intersect another light if there is one.
It should be realized that the preceding description of a method of
locating edges of ceiling lights is but one suitable technique. For
example, known methods of finding straight line patterns in a video
image include the use of Hough transforms, edge detection and
linking, and curve fitting.
Referring to FIG. 9a it is shown that the camera 112 configuration
is treated geometrically as a viewpoint 130 and an image plane 132.
The viewpoint 130 may be considered as the center of the camera
lens. Images are projected perspectively from an arbitrary point P
in three dimensional space onto point P, in the image plane 132,
along a line through the viewpoint 130. It is mathematically
convenient to consider the image plane 132 to be a unit distance
from the viewpoint 130. N is the unit vector normal to the image
plane 132. Thus units of distance measured in the image plane
correspond to the tangent of the angle from the normal N through
the viewpoint 130 perpendicular to the image plane 132. This
convention provides for the scaling of the view angle tangent with
respect to camera 112 pixel count as follows.
Referring to FIG. 9b it can be seen that the horizontal angle of
field of view of the camera 112 is designated as fovh and the
vertical angle of field of view is designated as fovv. The image
plane 132 is rectangular and is positioned symmetrically with
respect to the camera FOV, as is standard in most video cameras.
Npixh is the number of pixels 134 in a horizontal line and npixv is
the number of vertical rows of pixels 136. Image plane 132 (u,v)
coordinates are given in tangent units, respectively horizontal and
vertical, from the center 138 of the image plane 132. The following
equations convert pixel coordinates to tangent coordinates:
For a typical CCD video camera having an 8.5 mm focal length and a
conventional frame grabber the following relationships apply:
FIG. 10a illustrates, in accordance with one aspect of the
invention, a zenith gazing camera 112 mounted to the robot 110.
Distance from the camera 112 viewpoint to the ceiling 114 is "c".
The image plane u-axis is aligned with a vehicle forward axis. Yaw
angle, theta, is measured between the u axis and a long axis,
designated as A, of the hallway. The image of the ceiling as viewed
by camera 112 is illustrated in FIG. 10b.
The angle of rotation of the ceiling image on the camera 112 image
plane is equal to the vehicle yaw angle, as illustrated in FIGS.
10a and 10b. The precision of measurement accuracy depends in part
on the accuracy of identifying a linear edge, or boundary, of a
ceiling light 116 and also upon the length of the boundary. In a
typical environment, the edge of a light 116 may subtend 100 pixels
while the edge measurement may be accurate to within two pixels.
This corresponds to approximately 0.2 radians accuracy in yaw
measurement, or slightly more than one-half of a degree.
As the robot 110 moves a distance d along the floor 126, as
measured by wheel encoders or odometers, the zenith projection of
the view axis moves d units along the ceiling 114. Points in the
image of the ceiling move distance d' in image plane u-v units.
FIG. 10c illustrates this movement relative to vehicle 110
coordinates, that is, as if the vehicle 110 were stationary and the
ceiling 114 moved distance d. An analysis of similar triangles
yields the ceiling distance above the camera 112 viewpoint as:
Generally
Considering an example in which the camera 112 is 2.5 feet above
the floor 126, the ceiling 114 has a height of 10 feet and the
robot 110 moves two feet per second, then c=7.5 feet. In 250
milliseconds the robot 110 moves six inches. Therefore
d'=d/c=0.5/7.5 or 0.0666 tangent units. For a camera 112 having a
FOV of 55 degrees with 512 pixels per row, this motion corresponds
to 32 pixels. If c is unknown in advance, an image motion of 32
pixels within 250 milliseconds implies that the ceiling 114 is 10
feet above the floor, it being given that the camera 112 height
above the floor is 2.5 feet. Thus, ceiling height may be directly
inferred.
The accuracy of motion measurement is derived from pixel
"footprint" size on the ceiling 114 as follows. In the example
given above the fovh=55 degrees thus one pixel represents u=tan
(fovh/2)/256=0.002 tangent units. Hence, d=c*d'=7.5*0.002=0.15 feet
or 0.18 inches. While this error term may exceed that of the
instantaneous motion encoder accuracy it should be realized that
this error term is absolute, not cumulative, over time. Thus, if
motion encoder based measurements are accurate to approximately 1%,
visual observation of the ceiling 114 surpasses motion encoder
based dead reckoning accuracy after only 18 inches of floor travel.
However, the vehicle 10 platform may wobble somewhat due to floor
surface irregularities and absorption of acceleration in the
suspension of the vehicle 110 platform. A two degree tilt of the
vehicle 110 projects to a three inch error on the ceiling 114, or
roughly 17 pixels. If wobble of this magnitude is common, one
suitable method to reduce the effect of wobble on positional
registration is to use zenith gazing visual observations at
intervals of three feet or more of floor travel. Kalman filtering
techniques, based on covariance matrices of uncertainties, may also
be employed to merge visual and encoder based position estimates
thereby maintaining absolute position control.
The footprint ("headprint") of the viewscreen on the ceiling 114
for the example given above is approximately eight feet. If lights
116 are spaced more than four feet apart, and one set of lights is
burned out, there will be robot positions for which no lights are
visible. Using conventional CCD cameras and lenses, the FOV cannot
readily be widened beyond approximately 55 degrees without inducing
a "fisheye" type of distortion. This form of distortion, or
aberration, distorts the linearity of images of lines, which in
turn significantly complicates the geometry of image processing. A
preferred solution to this limitation is to aim the camera 112
obliquely upward from the horizon, viewing an area of the ceiling
ahead of the vehicle 110 and along a projected forward path of the
robot.
The following description sets forth the geometry and calculations
to infer vehicle orientation and lateral position in an
environment, such as a hallway, from an image of ceiling lights.
The following description makes use of an imaging device, such as a
camera, which is pitched up obliquely at an intermediate angle
between the horizon and the zenith. The ceiling lights are
preferably of rectangular shape and are aligned with the hallway.
The ceiling lights may be arranged with their long axis parallel to
or perpendicular to a long axis of the hallway. The lights may
comprise incandescent or fluorescent bulbs and may or may not be
covered. Preferably the lights present a pattern or alignment which
is substantially parallel to or perpendicular to the long axis of
the hallway. That is, the shape being detected may be either a line
boundary or a linear row of simple shapes, such as light bulbs. The
inferred axis of alignment is treated as a geometric line in the
following discussion.
It is convenient to center the origin at the viewpoint of the
camera 112 and to adopt right-handed Cartesian coordinates (x,y,z)
aligned with the hallway as follows. The z-axis is vertical, the
y-axis points down the hallway parallel to the long axis of the
hallway and the x-axis is perpendicular to the long axis of the
hallway. Position is referenced from the camera 112 and direction
is referenced with respect to the walls of the hallway. Hence the
designation "cam-wall" coordinates which will be employed
hereinafter.
FIG. 11a illustrates the general configuration of the cam-wall
coordinate system. The distance from a camera 150 to a ceiling 152
is c. The ceiling plane is characterized as
-infinity<x<infinity, -infinity<y<infinity and z=c. The
camera 150 is pitched up by an angle Pch radians and yawed over by
an angle Yaw radians. There is no roll component in that camera
raster lines are parallel to the ceiling, floor and horizon planes.
Pch is measured from the x-y plane verticallyto the viewplane
normal vector N. Yaw is measured as the angle between the y-z plane
and the vertical plane containing the vector N. From these
definitions, it is apparent that the normal vector N is given
by:
That is, the vertical component of N is sin(Pch). The horizontal
component is cos(Pch), which decomposes into x and y components in
the ratio cos(Yaw):sin(Yaw).
Perspective projection from cam-wall coordinates to image
coordinates is illustrated in FIG. 11b. A general vector P (x, y,
z) in three dimensional space is connected to the origin by a
straight line. It intersects the image plane 154 at
Image coordinates [u,v] from the center of the image plane 154 are
expressed with respect to the unit vectors U and V, namely
V is a unit vector perpendicular at both N and U, that is, the
vector cross product of N and U which is given by ##EQU1##
where I, J, K are the unit basis vectors of the (x, y, z) cam-wall
coordinates.
That is,
The image plane 154 coordinates of the image of a point P are the
projections of P' onto U and V, namely,
A row of ceiling lights along the axis of the hallway defines a
line, LO, which is parallel to both the walls and the floor. In
cam-wall coordinates, the equation of line LO is
where
As s goes to infinity, u and v approach the limits
[u,v].fwdarw.[uu,vv],
where
As seen in FIG. 11c the projected the image LO' of the ceiling line
LO approaches a vanishing point 156 on the screen. This vanishing
point 156 is the intersection of the images of all lines parallel
to LO, i.e. with all possible choices of xO and zO. Intuitively, it
is a point on a horizon where two parallel lines, such as railroad
tracks, would appear to converge and meet.
This converging line analogy is advantageously employed, in
accordance with a method of the invention, to determine the values
of uu and vv. That is, two lines within the image plane 154 are
selected which are images of ceiling features known to be in a
parallel relationship, such as the left and right boundary of a row
of ceiling lights 116 as in FIG. 10a. The intersection in image
plane coordinates of the two boundaries is then determined by the
substitution of the equation of one boundary into the other. The
determined intersection point may lie physically off the image
plane 54 but nevertheless yields values for the vanishing point uu
and vv. Pitch is thus
and yaw is
It should be noted that vv is independent of Yaw. The value of v is
therefore the horizontal line on the screen that is the image of
the horizon.
Returning briefly now to a consideration of FIG. 11a it should be
recalled that once camera pitch (Pch) is known, ceiling height may
be inferred from the motion of image features as the vehicle 110
moves along the floor. To further clarify the relevant geometry, it
is useful to consider a coordinate system which aligns with the
forward direction of the camera and vehicle motion. This is
accomplished by rotating the x-y plane of the cam-wall coordinate
system such that it aligns with the horizontal component of the
image plane 154 normal N. FIG. 11d illustrates this new coordinate
system. Note that the z-axis is in common with the cam-wall
coordinates while the x-axis the y-axis are replaced by a u-axis
and a w-axis whose basis vectors are
And
Z={0,0,1} (30)
The brace notation {u, w, z} denotes coordinates with respect to
the basis U, W, Z which will be referred to herein as the
"cam-floor" coordinates system. Both the cam-wall and cam-floor
coordinate systems use the camera viewpoint as the origin 150.
Conversion from (x,y,z) to {u,w,z} is accomplished by the
transformation: ##EQU2##
The inverse transformation is accomplished by ##EQU3##
Referring to FIGS. 11b, 11c and 11e and considering the trajectory
of a point P on the ceiling in cam-floor coordinates as the robot
moves forward, u=uO, w=s and z=zO, where s is the parameter of
distance travelled in direction W. The image of this line is
derived by projection onto the image plane 154 as follows. The
image plane U basis vector is the same as for cam-wall coordinates,
as previously set forth in Equation 28.
The image plane 154 normal in cam-floor coordinates is given by
N={O, cos(Pch), sin(Pch)} (33)
and the image plane 154 basis vector (V) is
Thus P projects onto the screen at
where
Image plane 154 coordinates are derived by projecting p' onto U and
V,
These image lines, which represent the streamlines of optic flow,
all radiate from the vanishing point,
Transforming the origin of image plane coordinates to this point,
using the primed bracket to denote the new image plane coordinate
system,
implies that an arbitrary optic flow line maps into
Thus, the slope of the optic flow line is
v'/u'=zO/(uO*cos(Pch)). (41)
It is noted that the v' component is independent of uO which
simplifies the computation of ceiling height as will be shown.
FIG. 11e illustrates the w-z component of image plane and ceiling.
The u-component can be ignored in computing zO as previously shown.
As the vehicle 110 moves forward distance d in the direction W, the
footprint ("headprint") of the screen moves distance d along the
ceiling. Any point P1 moves distance d to P2; the corresponding
images on the screen are P1' and P2', separated vertically by d' in
the image plane. That is, v2'-v1'=d'.
As can be seen d' and d" are a side and a base, respectively, of a
triangle similar to the one formed by the image plane 154 w-axis
and the line 0-P2'. Thus,
Inasmuch as d" and d are corresponding parts of similar triangles
0-P1'-Q and 0-P1-P2 whose altitudes, indicated by the vertical
dashed lines in FIG. 11e, are v1'*cos (Pch) and zOit can be
realized that
Equation 44 gives ceiling elevation as a function of image plane
154 pitch and the image plane 154 vertical coordinates, [v1',
v2',], of two successive images of a feature, the vehicle traveling
a distance d between images. The ratio of d" to d is the same as
the ratio of the w-component of ranges from the origin to P1' and
P1, respectively, by virtue of similar triangles 0-P2'-R and
0-P1-S. Thus,
which implies
(w1=d*v2'*(1-v1'*sin(Pch)*cos(Pch))/(v2'-v1'). (46)
Thus, the invention provides for range to be inferred from the same
image data that yields ceiling height. Lateral displacement of the
robot 10 from the tracked ceiling feature is derived below.
Recalling from Equation 41 that the slope of the image line is
v'/u'=zO/(uO*cos(Pch) the lateral position of the tracked feature
relative to the robot path (u-axis coordinate) is
If ceiling height is known, either from a database, sonar readings,
or from the optic flow analysis as described above, the position of
the robot 110 with respect to the center line LO, or any other
measurable line, of the ceiling may be derived in hallway
coordinates as described below. Robot pitch and yaw are also
necessary inputs. As shown in the preceding discussion, pitch and
yaw may be derived from the image plane 154 coordinates of the
vanishing point 56.
The cam-wall origin and the line LO described previously define a
plane known as an epipolar plane.
The system includes a means for obtaining an image of a surface
which overlies a robot or a projected path of the robot, the
surface having one or more sources of illumination disposed
thereon; means, coupled to the obtaining means, for detecting
within the image a location of the one of more sources and means,
coupled to the detecting means, for generating, from the detected
source location or locations, vehicle navigation information. The
generating means is shown to include means for determining at least
an offset distance and an angular displacement of the vehicle
relative to the location of the source within the image. Further in
accordance with the invention there is disclosed a method of
providing navigation related information for a mobile robot. The
method includes the steps of (a) obtaining at least one image of a
ceiling having one or more distinct visual features, the ceiling
overlying at least the projected path of the robot; (b) locating
within the ceiling image the one or more distinct visual features;
(c) detecting a boundary of the distinct visual features; (d)
generating at least one reference line relative to the detected
boundary; and (e) determining a location of the robot relative the
reference line.
Yet another means of mapping suitable for inclusion as a guidance
system in the present invention is the triangulation from plural
radio frequency beacons, which is known in the art. Such a guidance
system is shown and described in U.S. Pat. No. 5,974,347 (Nelson,
issued Oct. 26, 1999), which is herein incorporated by
reference.
In this embodiment, the guidance system uses three stationary radio
sources placed in known locations and a receiver with a rotating
directional antenna located on the robot to triangulate the robots
position and to build a map during the training of the robot. To
start the programming phase of operation, the user places the
continuous wave transmitters 420A, B, and C in a right angle
formation somewhat outside the area to be cleaned. Although, FIG.
12 shows one particular platform design with this guidance system,
any platform can be used, including but not limited to the platform
design shown in FIG. 1. The following description is for
illustrative purposes only and not meant to limit the
invention.
Referring to FIG. 12, the platform 10 includes a whip antenna 440A
that receives data from a hand-held programmer transmitter 422.
Another whip antenna 440B, included on the platform, communicates
with a central processor or computer 434 via a transceiver
interface 432. A directional loop antenna 436 receives radio
frequency signals from continuous wave transmitters 420A, 420B, and
420C. A housing 438 supports these antennas. Directional loop
antenna 436 is located between the whip antennas. A selector switch
548 and a keypad/display 464 are mounted for convenient access near
the whip antennas.
FIG. 13 is a perspective view of one particular embodiment of the
directional loop antenna 436. The antenna is a coil of several
turns of wire wound on a form 437. The form is a plastic cylinder
attached by glue to a plastic support tube 470. Leads from the coil
pass down the inside of the support tube to two slip rings 466A and
466B. A pair of contact brushes 68A and 68B connect the slip rings
to leads, which carry the radio frequency signal to a radio
frequency amplifier 510 in FIG. 15. The support tube is attached to
a wheel 472. Wheel 472 is driven by friction contact on its
circumference by a shaft 476. Shaft 476 is directly connected to a
pulley 474. Pulley 474 is connected to a pulley 480 by a drive belt
478. Pulley 480 is connected to a motor shaft 490 of a direct
current electric motor 488. A notched disk 486 is centered on shaft
90 to chop a light beam produced by a light source 482 and a light
sensor 484.
FIG. 14A shows an example x-y coordinate system defined by the
locations of continuous wave transmitters 420A, 420B, and 420C.
These transmitters are shown as points T1, T2 and T3, respectively,
in a right angle configuration. The location of home cleaning robot
of FIG. 12 is depicted as M in FIG. 14A. Angle A formed by T1, T2
and M defines a locus of points which is a circle 492A with an
offset a on the x-abscissa. An equation 492B then describes circle
492A. Similarly Angle B formed by T2, T3 and M defines a locus of
points which is a circle 494A with an offset b in the x-abscissa,
and an offset c in the y-ordinate. An equation 494B then describes
circle 494A. The solution of the two simultaneous circle equations
provides the value x in an equation 496 and the value y in an
equation 498.
FIG. 14B shows circle 492A with its radius r1, and its offset a. An
equation 100 calculates radius r1 and an equation 502 calculates
offset a from the value of angle A and distance d. Angle A is the
angle measured by the directional loop antenna between transmitters
T1 and T2. Distance d is the distance between transmitters T1 and
T2.
FIG. 14C shows circle 494A with its radius r2 and offsets b, and c.
An equation 504 calculates radius r2. Equations 506 and 508
calculate offsets b and c, respectively, from angle B and distances
d and e. Angle B is the angle measured by the directional loop
antenna between transmitters T2 and T3. Distance d is the distance
between transmitters T1 and T2. Distance e is the distance between
transmitters T2 and T3.
FIG. 15 is a functional block diagram illustrating the system
operation in the present invention. The three continuous wave
transmitters send a constant signal to directional loop antenna
436. The loop antenna is rotated at a constant speed by direct
current motor 488. The speed of the motor is controlled by a phase
locked loop 512. The phase locked loop receives input from light
sensor 484. A clock 514 provides a reference frequency for the
phase locked loop and a counter 130. The frequency of the clock
input to counter 530 can be designed for about 4096 Hertz. The
signal from the directional loop antenna is amplified by a radio
frequency amplifier 510. The amplified signal is fed to filters
516, 518, and 520 tuned to each one of the continuous wave
transmitters. The T1 filter is tuned to the frequency of
transmitter 420A. Likewise the T2 filter is tuned to the frequency
of transmitter 420B, and the T3 filter is tuned to the frequency of
transmitter 420C. The outputs of each of these filters are fed into
signal conditioners 522, 524, and 526 respectively. Functions of
these signal conditioners will be described in more detail in FIG.
16. These signal conditioners feed a sequencer 128 which operates
to assure that the proper sequence of pulses control counter 530
and a load pulse generator 532. Circuit description of the
sequencer is provided in more detail in FIG. 17.
The pulses generated by the signal conditioners are also held in a
latch 534. The information in the counter and latch are selected by
a multiplexer 536 for input into a universal asynchronous receiver
transmitter, UART 540. Load control signals for the UART are
provided by the load pulse generator and a divide-by-N circuit 538.
The serial output of the UART drives a modulator 566, which
modulates a transceiver 546. This transceiver then transmits and
receives signals from remote transceiver interface 432 of FIG. 12.
All the transceivers used for data communication in this invention
may be of the type used in cordless telephones commonly used in the
industry. Thus any of the commercial cordless telephones will
suffice. An audio coupler, not shown, may be used to make
connection to the microphone input of the cordless handset. An
alternate transceiver is the Micro-T transceiver manufactured by
Adcon Telemetry of Boca Raton, Fla.
A manual control receiver 544 receives signals from hand-held
programmer transmitter 422. Selector switch 548 is used to select
the programming signal in the program mode, or the automated signal
in the automatic mode of operation. A pulse shaper/conditioner 542
conditions the signal for serial input to UART 540. The serial data
is converted to parallel data in UART 540 and is provided to a
steering latch 550 and a drive latch 552. Data in latch 550 is
converted to analog form by a D/A converter 554. The analog signal
then feeds into a power driver and comparator 556, which controls
steering motor 426. Feedback to comparator 556 is provided by a
potentiometer 450, which is mechanically connected to the cross arm
as previously described. This feedback provides for proportional
control of steering motor 426. Data in latch 552 are buffered by
drivers 558A, B, C, and D to relays 560A, B, C, and D respectively.
Relays 560A and B connect power to drive motor 562. Relays 560C and
D connect power to a speed control motor 564. Motor 564
mechanically turns a rheostat 428, which controls the current
through drive motor 562 to control speed of movement.
FIG. 16 shows the functional blocks within signal conditioners 522,
524, and 526 of FIG. 15. These conditioners are analog circuits
commonly used in the industry and are available from National
Semiconductor Corp., Santa Clara, Calif. They consist of an
envelope detector 568, an inverter 570, a differentiator 572, a
zero crossing detector 574, and a pulse generator 576.
FIG. 17 shows a detailed circuit diagram of a sequencer 528.
Operation of this circuit serves to allow only the proper sequence
of pulses T1, T2, and T3 to be latched and read. This is required
because of the symmetrical nature of the antenna pattern of the
directional loop antenna. In certain locations of the cutting area,
the order of reception of signals from the continuous wave
transmitters may be backwards. The function of sequencer 528 is to
allow only a forward sequence to assure the correct clock count and
thus the correct angles between the transmitters. The sequencer is
composed preferably of CMOS logic, and functions as follows. D flip
flops U1, U2, and U3 are initialized to a 1,0,0 state upon
power-up. A power-on reset 588 is produced by resistor R and
capacitor C. Power-on reset is inverted by inverter U4 producing a
momentary logic 1 output from U4. A logic 1 input to one of the
inputs of NOR gate U5, U14, and U16 produce a logic 0 input to
inverters U6, U15, and U17. The outputs of these inverters are
logic 1 which sets flip flop U1 to logic 1, and resets flip flops
U2 and U3 to logic 0. The sequencer is now initialized.
In this state only a T1 pulse 650 from signal conditioner 522 of
FIG. 15 will change its state. When the T1 pulse comes in, it feeds
through NAND gate U7 producing a logic 0 pulse to the input of
inverter U8. The output of inverter U8 is a logic 1 pulse which
sets flip flop U2 to logic 1, and resets flip flop U1 to logic 0.
The output of NAND gate U7, a sequencer signal 596, is fed into an
input of NAND gate U13. Since the other inputs to U13 are logic 1,
the output of U13, a sequencer output 660, is a logic 1 pulse. Any
other input before this point would not produce a sequencer output
pulse nor would it change the state of the flip flops.
After the T1 pulse, the state of flip flops U1, U2, and U3 is
0,1,0. The output of flip flop U2 is a logic 1. The state of U1 is
logic 0 which prevents the T1 pulse from getting through NAND gate
U11. The logic 1 state of flip flop U2 does allow a T2 pulse 252 to
get through NAND gate U9 to produce a logic 0 pulse, a sequencer
signal 598. Signal 598 is transmitted through NAND gate U13 to
produce a logic 1 pulse on sequencer signal 660. Signal 598 is
inverted by inverter U10 to produce a logic 1 pulse which sets flip
flop U3 to logic 1 and resets flip flop U2 via NOR gate U14 and
inverter U15. After the T2 pulse, the state of flip flops U1, U2,
and U3 is 0,0,1.
In this state U1 and U2 are logic 0 which prevents the T1 pulse
from getting through NAND gate U7. Likewise the T2 pulse is
prevented from getting through NAND gate U9. Only a T3 pulse 654 is
allowed to get through NAND gate U11 to produce a logic 0 pulse on
a sequencer signal 600. Signal 600 is transmitted through NAND gate
U13 to produce a logic 1 pulse on sequencer signal 660. Signal 600
is also inverted by inverter U12 to produce a logic 1 pulse which
sets flip flop U1 to logic 1 via NOR gate U5 and inverter U6. The
logic 1 pulse output of inverter U12 also resets flip flop U3 to 0
via NOR gate U16 and inverter U17. After the T3 pulse, the state of
flip flops U1, U2, and U3 is returned back to the original state of
1,0,0. The process repeats that operation. Whether the input order
of pulses is forward, T1, T2, and T3, or in reverse, T3, T2, and
T1, the output of the sequencer, signal 660 is always in the
forward order, T1, T2 and T3.
Another mapping input commonly used in military guidance systems is
the electronic compass. The compass input, like that from the other
means described, is used to create a map by storing directional
data as the platform is manually led through the desired path.
Another process of use is that the robot is placed in learning mode
by temporarily closing a sensor contact (push button) or by
infrared (IR) or radio frequency (transmitted) remote command or by
voice command. In this mode sensor input is encoded in timed
increments and stored in memory by the microprocessor. The home
cleaning robot is manually pushed through the desired path by the
user or directed remotely with a remote control device. During this
learning period the output of the drive wheel motor and application
specific sensors are recorded to read-write memory by the CPU
optionally along with the output of the electronic compass thereby
making a record of wheel revolutions, application events, and a
record of direction during the task during successive time periods.
At this point the home cleaning robot is said to be trained and the
activity mapped. The end of the training may be input by manual
sensor input (e. g. releasing a push button) or by reaching a
sensed goal such as light level, radio frequency source (or
reflector) IR source (or reflector) or some other activation means.
Subsequently, the toy may be placed back at the starting point and
placed in "playback mode" manually wherein the CPU recalls the
stored encoder and direction data to control the motors (e. g.
controls drive motors to reproduce same encoder timing and count)
while comparing time and direction data during movement.
In the event of an obstacle in the path, the control system may
become adaptive in that when obstacles are sensed by contact
switches, sonar, or light, it will perform programmed record
backing and turning avoidance movements and direction around the
obstacle and record the deviation so as to store a vector from the
point of obstruction in the map and then calculate a new vector
back to a resumption point along the obstructed path. It should be
recognized that this is a general description and that variations
may be embodied in the control system for application-specific
circumstances without departing from this teaching.
It should be further recognized that training and adaptation could
be mixed. For example if the user grasps the home cleaning robot
during operation and manually moves with the teaching mode engaged,
the new motion would be recorded and inserted as part of the
trained activity so as to allow piece-meal training. In this way a
user may edit a task may by simple manual demonstration.
Once tasks are learned software may be additionally be provided for
communication and storage of a task to a storage means such as a
floppy disc, memory stick, a computer, or a like home cleaning
robot by a hardwired connection or wireless communication.
Optionally a platform may be provided with enough memory and an
interface to allow storage and replay of plural trainings. In this
manner a single home cleaning robot can be trained to perform a
number of different tasks.
In a first embodiment, the platform is provided with a low energy
cleaning implement. One embodiment of a low energy cleaning
implement is a nonwoven electrostatic, cloth cover, such as the
Swiffer.RTM. electrostatic cleaning clothes available from Procter
& Gamble Company, Cincinnati Ohio. The cover is provided with
cut outs on the under side to allow the wheels, or tracks to make
contact with surface on which the home cleaning robot is operated.
The underside of the platform may be further equipped with a foam
pad or pad(s) to insure that the cover is brought in compliant
contact with the underlying surface. The covers may connected to
the platform in a variety of ways, including but not limited to
wherein the cover is removably adhesively attached, wherein a
frictional grip is used to attach the covers, wherein a mechanical
engagement is used to attach the covers to this platform.
In an alternative embodiment, the low energy cleaning implement is
a nonwoven wet cloth impregnated with a cleaning solution, such as
the Swiffer.RTM. cleaning clothes available from Procter &
Gamble Company, Cincinnati Ohio.
In a further embodiment of the present invention, the cover used is
provided with the appearance of a bunny rabbit with large ears that
act to dust base boards. The may also have a an adaptive behavior
mode where it avoids light thus allowing it to be placed under
furniture where it will dust and acting very much like a small
nocturnal animal.
The method of use in one embodiment is to train the home cleaning
robot by switching it into training mode and manually moving it
over the surface to be cleaned. At the completion of the cleaning
task training mode is switched off. Subsequently, the now-trained
home cleaning robot set in play-ack mode can repeat the cleaning
motions it was manually led through. In this embodiment contact
sensors or proximity sensors on the outward facing edge of the
platform provide for adaptive navigation so that the task may be
completed even if obstacles subsequently are placed in the
path.
In the second embodiment, the platform is provided with an electric
spray pump and a fluid tank or container. Preferably the container
is filled with a cleaning or deodorizing fluid that is benign to
humans. The platform is to be additionally equipped with a
disposable towel or a removable towel wiping means affixed to the
underside of the home cleaning robot so as to have compliant
contact with the underlying surface such as over a foam material.
The spraying feature is controlled by a momentary contact switch
(push button) mounted flush with the surface of the cover. The
method of use is to train and then to subsequently operate. It is
to be understood that if the home cleaning robot encounters
obstacles near spray points it will not spray at those points.
In a third embodiment the home cleaning robot may be provided with
a wax or polish impregnated pad or towel attached to the underside
and having complaint contact with surface by means of a foam
support. Alternatively a polish or wax may be dispensed onto the
surface by an electric spraying pump, in which case the pad or
towel would not necessarily be impregnated with a wax or polish. It
is to be understood that a wide range of polishes, oils, or waxes
might be provided depending on the nature of the surface to be
polished or waxed. The methods of use follows the pattern of
training and then adaptive operation as previously described.
In a fourth embodiment the home cleaning robot is applied to weed
killing. In this embodiment the platform is preferably provided
with driven tracks rather than wheels and may be further provided
with a solar recharging means for recharging the power cell such an
cover having a amorphous silicon solar cell (film) on its upper
surface. The home cleaning robot is further equipped with a digital
imaging means. The platform in this instance is provided with a
sealed cartridge from which a safe herbicide may be dispensed or
alternatively equipped with a magnifying glass means of
concentrating solar energy on suspect weeds and safely destroying
them by heating. One or more passive radio frequency (PRF) tags are
provided to be implanted in lawn areas where weed killing is to
take place. The home cleaning robot is provided with a (PRF) tag
exciting transmitter and a receiver for detecting resonating
tags.
The method of operation of the fourth embodiment requires training
to the extent that the home cleaning robot is placed over typical
weed types and typical grass and the images are recorded.
Subsequently the home cleaning robot is moved a radial distance
away from the PRF homing tag that will define an approximate limit.
The home cleaning robot is then placed in operative mode wherein it
spirally moves in toward the PRF tag scanning for weed image
patterns and releasing spray or focusing sunlight onto the
offending weeds when they are found.
In the fifth embodiment the platform is equipped with a digital RF
transmitter and receiver and PRF homing tags with separate resonant
frequencies are used to tag articles which may be misplaced. An LCD
window and keypad may also be provided with the platform for manual
I/O.
The method of operation of the fifth embodiment requires that PRF
tags are placed on articles that may be misplaced such as purses,
keys, wallets, clothing, and the like. During training the name of
each tagged article is encoded into the home cleaning robot after
being presented to it in training mode. The home cleaning robot is
further trained by manually leading it through a general search
path. In operation it will travel that path and alarm when it is in
close proximity to a PRF tag selected from a menu of learned tags.
It should be recognized that the use of learned RF tags permits
games of hide and seek, competitive searching, and many other play
activities.
In the sixth embodiment, the platform is provided with an air
filter or an activated carbon air purifying means, or both. The
method of operation is to train the home cleaning robot to follow a
path through a room or multiple rooms thus purifying and/or
cleaning air over a wider area than would be possible with a
stationary filter or air purifier. The platform may additionally be
provided with a sensor that detects smoke or gases and which
provides an alarm of unsafe conditions. Such sensing technology is
readily available from a wide range of sources including any
Walmart.
In the seventh embodiment, the platform is provided with an odor
detecting sensor means and a means of spraying an odor reducing
substance. One such substance is cyclodextrin in water. Various
odor reducing fluids suitable for use are available from Procter
and Gamble Company, Cincinnati, Ohio. The home cleaning robot in
this case is trained to "patrol" a path. It's path programming is
overridden when strong odors are detected and it moves along the
gradient of increasing intensity.
In an 8.sup.th embodiment the platform is provided with a means of
dispensing aromatic sprays such as, but not limited to, essential
oils and perfumes. The method of use is training the home cleaning
robot to follow a path with positions where it is trained to
dispense aromatic sprays. The dispensing means can consist of a fan
blowing over an cartridge with an odor dispensing wick, a spraying
means, or an atomizing means such as an oscillating membrane. The
platform may optionally be provided with plural aromatic or odor
producing means so as to produce different odors at different
locations.
In a 9.sup.th embodiment the platform is provided with an infrared
(IR) or sonar detection means in order to act a security measure.
It is trained to "patrol" a path or to travel to different
locations at different times, and provides an alarm in the event
motion is detected. A wide range of motion detection electronics
are available from Radio Shack stores.
In 10.sup.th embodiment the platform is provided with a vacuuming
means. In this embodiment the vacuuming means may be supplemented
by drawing the vacuum through an electrostatic cloth, such as the
Swiffer product available from Procter & Gamble, Cincinnati,
Ohio. Alternatively a conventional brush a vacuum arrangement may
be used. It is trained to vacuum as desired. Such a home cleaning
robot may be programmed to avoid light so that it preferentially
stays and vacuums under furniture where full-sized vacuum cleaners
do not reach and dust and pet hair collect.
In an 11.sup.th embodiment the platform is provided with a means of
cutting or killing grass such as a string, hot wire, spray, or
solar heat concentrating magnifying glass and trained to follow the
edges of walkways and driveways and the like cutting or destroying
over-growing vegetation.
In a 12.sup.th embodiment, the platform is provided with a suction
means such as a vacuum (a reverse of a skirted air cushion
levitation means) so that it is held on a wall or other
non-horizontal surface and provided with a dusting means such as an
electrostatic cleaning cloth or dust mop. Again the home cleaning
robot is trained to follow a particular path. In this instance a
remote means of training guidance is preferred.
In a 13.sup.th embodiment a floating platform is provided with a
propulsion means such as a flexible fish-tail, paddling feet, or
the like wherein the extremities or tail have a lightly abrasive
cover. This platform may further be equipped with a soap dispensing
or deodorizing means. It is employed by the child as bath home
cleaning robot and acts to clean the bathtub after use. This
platform would be primarily trained and guided by electronic
compass. In a variation, without the abrasive cover, it could be
placed in laundry tub to agitate the laundry and dispense
detergent.
In a 14.sup.th embodiment a tracked platform or one with
high-traction wheels is provided with a pushing means (this might
have the appearance of a animalistic bulldozer). The home cleaning
robot is trained to patrol a path and when encountering obstacles,
push them away from the path or to a particular location. This home
cleaning robot would be of particular value to a teenager.
In a 15.sup.th embodiment a tracked platform, or one with
high-traction wheels is provided with a blade or equipped with a
means of dispensing salt or other ice melting substances. It is
trained to patrol a walkway or driveway and remove snow or dispense
ice melting substances. The platform would optionally have a solar
charging means and a flashing light means such as an LED for use in
the dark after training. The home cleaning robot would optionally
have a remote guidance control so that the child could remain in a
warm house and guide the home cleaning robot outside. The same home
cleaning robot can also be trained by the child to dispense
fertilizer or seed in the spring and summer.
In a 16.sup.th embodiment a larger platform is used capable of
supporting a garbage can or optionally being a wheeled can. The
platform would optionally be provided with a solar recharging
means. The child would train the "garbage can" by wheeling it from
its storage position to a garbage pick-up position on an
appropriate schedule. The can might optionally be provided with
odor reducing means whereby it would spray the contents
periodically with an odor reducing fluid or sterilizing fluid.
In a 17.sup.th embodiment the home cleaning robot is equipped with
a video camera and is trained to patrol a path. The platform is
provided with a wireless Internet interface so that the images can
be remotely accessed. Its play value is manifold.
In an 18.sup.th embodiment the home cleaning robot is provided with
some and gas detection means and is trained to patrol a path. It is
further provided with a means of dispensing a fire-retardant
substance. The platform is further provided with IR sensors. If, on
its trained path, the IR sensors detect emissions at combustion
temperatures, the home cleaning robot will dispense the fire
retardant substance via a pump and nozzle.
In a 19.sup.th embodiment the home cleaning robot is provided with
a track or wheels having permanent magnetic surfaces or
sub-surfaces. The home cleaning robot is further provided with an
electrostatic cloth. The home cleaning robot is trained to follow
paths on ferromagnetic surfaces such as automobiles or
appliances.
In a 20.sup.th embodiment the home cleaning robot is provided with
a near-field motion detecting means. Such a means may include, but
is not limited to, a photodiode-photoreceptor pair, sonar, or
tactile contacts such as fine optical fibers wherein motion of the
fiber changes light transmission properties. The home cleaning
robot is trained to patrol a path where insects are suspected or
present. The home cleaning robot may dispense water, an insect
repellant, or emit ultrasound to rid the locale of insects.
In a 21.sup.st embodiment the platform is provided with tracks or
wheels having velcro-like micro-hooks (or velcro). The platform is
further provided with a cleaning means such as a dusting cloth,
cleaning fluid, or vacuum or some combination. It is trained along
paths that involve highly irregular, cloth surfaces such a
furniture or bedcovers.
In a 22.sup.nd embodiment, the platform is provided with a metal
detecting means. Such means are readily available from a wide range
of suppliers. The home cleaning robot is equipped with a compass
navigation means and a triangulating beacon means and trained by
locating at perimeter points. (It does not have to manually moved
along the perimeter.) In operation it covers the area within the
perimeter and can be used to search for lost jewelry, coins, keys,
and the like. It can also be used to prospect for various
"treasures" to be found in parks and the like.
In a 23.sup.rd embodiment, a small platform is provided with a
soft, pliant tracks. The method of use is to train the home
cleaning robot to travel on a human back delivering a back rub.
Other and similar non-enumerated embodiments are similarly possible
as will now become apparent by combining a platform with a similar
task-enabling means and a cover and personality consistent with the
task behavior. They include:
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of receiving signals from sensors carried on or in
living organisms to monitor temperature, blood pressure, pulse
rate, motion, perspiration, or odors or some combination
thereof.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of detecting the direction and intensity of sound at
pre-determined frequency ranges. Such a home cleaning robot can be
used to detect abnormal noise in the home such as a water leak, a
faulty motor, or an alarm. It will also can give the appearance of
listening and moving toward a pers on speaking.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of receiving and broadcasting sound so as to simulate
various acoustic phenomena such as moving sound sources or
time-separated sound sources such as spatially displaced
instruments in an orchestra or band. Such a home cleaning robot can
be used in lieu of stationary loudspeakers.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of magnetic attachment and an electrostatic cloth
whereby the home cleaning robot can dust ferromagnetic surfaces
such as automobiles and appliances.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of attachment to a smooth surface such as a vacuum
between the home cleaning robot and surface or by means of an
aerodynamic force, whereon said home cleaning robot can perform
some function to the surface. An example would we a window cleaning
or mirror cleaning home cleaning robot.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of walking locomotion and a dirt or dust collecting
capability so as to be able to gather dirt and dust from irregular
surfaces such as the interior of an automobile or stairs.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means propulsion under water. Said home cleaning robot may
optionally record or transmit sound or images.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a lighter than air means of flying and provided with sound and
video recording or transmitting means.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of detecting higher energy radiation (such as
microwave, x-ray, or nuclear) and traveling toward such radiation
or alarming if such radiation exceeds predetermined thresholds.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means detecting raised or inverted folds of cloth on a flat
surface such as an ironing board and stretching them flat.
Generally this may be done a platform with a pair of wheels
additional to the driving wheel pair. The home cleaning robot,
detecting the fold by simple optical means (e.g. diode
photodetector pair), positions itself over the fold with a pair of
wheels on each side at which time each pair of wheels is caused to
turn opposing one another.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means traversing rain gutters on roofs and removing leaves
and other debris from the gutter. In this instance a tracked
platform may be used and the platform is to be optionally provided
with a solar recharging means. The debris or leaves are removed by
a one arm scoop wherein the scoop, lifted, may be rotated around
the arm to dump the scooped debris over the edge of the gutter.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means delivering paint to surfaces. The home cleaning robot
is used by training to cover a typical area shape and size and then
operated to cover wider and wider areas.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of delivering chemistries or radiation to reduce
mildew, moss, and other growth on the roofs of buildings, said
robot being waterproof and provided with a solar power generating
means.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of detecting ground moisture and selectively
delivering water to arid areas of gardens near flowers and other
shrubbery.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of detecting pet feces on lawns and kennel floors and
gathering said feces by means of a one-armed scoop where the scoop
is capable of rotating around the arm.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot is
provided with a soft plastic or rubber surface and a rapid, but
intermittent propulsion means so to act as artificial prey for
cats, dogs, or children with hunting instincts (in lieu of small
animals).
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of cellular communication such as a cellular phone
capable for remote mobile acoustic monitoring.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of cleaning or sterilizing food serving areas such as
tables with depressed surfaces for food in lieu of dishes.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a tracked means of propulsion so as to traverse fields, woods,
and the like. Said home cleaning robot to be provided with
photosensitive areas which when illuminated by a laser strike
provide for an acoustic or motional response so as to provide a
non-lethal outdoor hunting experience where harmless laser pens or
pointers used as "weapons".
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a grinding or mulching means for use in reducing the volume of
garbage or trash in a container.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a paint or dye spraying means to prepare banners, flags, and
paintings.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive home cleaning robot provided with a
powder spraying means to prepare sports playing areas for various
games such as hopscotch, soccer, and the like.
In yet another embodiment the present invention is comprised of an
autonomous, trainable, adaptive mobile home cleaning robot provided
with a means of recording it motions in a form or format that can
be transferred to a full sized appliance or vehicle. For example,
but not limited to, a home cleaning robot lawnmower that can be run
over the lawn, not cutting, wherein its recorded path can be
subsequently downloaded to a robotic lawn mower with hazardous
blades that could not be used by a child.
Although particular versions and embodiments of the present
invention have been shown and described, various modifications can
be made to these home cleaning robots without departing from the
teachings of the present invention. The terms used in describing
the invention are used in their descriptive sense and not as terms
of limitation, it being intended that all equivalents thereof be
included within the scope of the claims.
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