U.S. patent application number 11/305941 was filed with the patent office on 2007-06-21 for autonomous load/unload robot.
This patent application is currently assigned to Betzalel Robotics, LLC. Invention is credited to Howard Mark Garon, Meyer Gross.
Application Number | 20070140821 11/305941 |
Document ID | / |
Family ID | 38173698 |
Filed Date | 2007-06-21 |
United States Patent
Application |
20070140821 |
Kind Code |
A1 |
Garon; Howard Mark ; et
al. |
June 21, 2007 |
Autonomous load/unload robot
Abstract
An autonomous robot for loading and unloading cargo of a cargo
container includes a first vertical member; a second vertical
member spaced in substantially parallel relation to the first
vertical member; and a cross-member secured to the first and second
vertical members in a substantially perpendicular orientation
thereto. The robot further includes a first arm and a second arm
secured to the cross-member and extending in a forward direction
with respect to the robot. The robot also includes means for
imparting vertical movement to the cross-member along the length of
the first and second vertical members and means for imparting
horizontal movement to the first and second arms along the length
of the cross-member. Means for imparting motive force to the robot
is/are provided. A processing unit is configured to control
directional movement, loading, and unloading routines of the robot.
A method for loading/unloading the container is also disclosed.
Inventors: |
Garon; Howard Mark; (Silver
Spring, MD) ; Gross; Meyer; (Brooklyn, NY) |
Correspondence
Address: |
THE WEBB LAW FIRM, P.C.
700 KOPPERS BUILDING
436 SEVENTH AVENUE
PITTSBURGH
PA
15219
US
|
Assignee: |
Betzalel Robotics, LLC
Port Washington
NY
|
Family ID: |
38173698 |
Appl. No.: |
11/305941 |
Filed: |
December 19, 2005 |
Current U.S.
Class: |
414/618 ;
414/416.01; 414/730 |
Current CPC
Class: |
B25J 9/026 20130101;
B65G 67/08 20130101; B25J 9/0084 20130101 |
Class at
Publication: |
414/618 ;
414/730; 414/416.01 |
International
Class: |
B65B 69/00 20060101
B65B069/00 |
Claims
1. An autonomous robot for loading and unloading cargo of a cargo
container, wherein the robot is comprised of: a first vertical
member; a second vertical member spaced in substantially parallel
relation to the first vertical member; a cross-member secured to
the first and second vertical members in a substantially
perpendicular orientation thereto; means for imparting vertical
movement to the cross-member along the length of the first and
second vertical members; a first arm and a second arm secured to
the cross-member and extending in a forward direction with respect
to the robot; means for imparting horizontal movement to the first
and second arms along the length of the cross-member; means for
imparting motive force to the robot; and a processing unit
configured to control directional movement, loading, and unloading
routines of the robot.
2. The autonomous robot of claim 1, further comprising environment
sensing hardware secured to the robot, wherein the environment
sensing hardware is selected from one or more of: a multi-element
passive photon detector; a multi-element or single element sound
transducer; a multi-element or single element thermal sensor; a
multi-element or single element passive radio-frequency sensor; a
multi-element or single element active radio-frequency transducer;
and a gas/liquid sampling sensor.
3. The autonomous robot of claim 1, further comprising a conveyor
extending in a rearward direction from the robot.
4. The autonomous robot of claim 3, wherein the conveyor includes a
loading shelf adapted to receive cargo from the first and second
arms of the conveyor, wherein the loading shelf is situated such
that in a first position, vertical travel of the cross-member is
obstructed by the shelf, and such that in a second position,
vertical travel of the cross-member along the length of the first
and second vertical members is unobstructed.
5. The autonomous robot of claim 1, wherein the means for imparting
vertical movement of the cross-member include at least one: a
linear actuator; a pulley; a belt drive; and a expanding
member.
6. The autonomous robot of claim 1, wherein at least one of the
first and second arms is non-articulated, articulated, rotatable,
or a combination thereof.
7. The autonomous robot of claim 6, wherein the first arm is
configured to move independently of the second arm.
8. The autonomous robot of claim 6, wherein at least one of the
first and second arms includes a pressure sensor for conveying
pressure data to the processing unit relating to an amount of
pressure applied to the cargo.
9. The autonomous robot of claim 1, wherein the means for imparting
horizontal movement of the first and second arms includes at least
one: a linear actuator; a pulley; a belt drive; and an expanding
member.
10. The autonomous robot of claim 1, wherein the means for
imparting motive force to the robot include at least one of: a
retractable foot; one or more treads; and a plurality of
wheels.
11. The autonomous robot of claim 1, wherein the processing unit is
configured to: detect the size of the cargo; detect an edge of the
cargo; optionally detect a wall, ceiling, or floor of the cargo
container; detect shifted cargo and the position thereof; create
loading and unloading strategies based upon the size of the cargo;
optimize the loading and unloading strategies during the course of
loading and unloading, respectively; conduct self-tests to ensure
operational functionality of the robot; receive external queries;
or detect unanticipated movement within a predefined perimeter.
12. The autonomous robot of claim 1, further comprising a third and
fourth vertical member secured in substantial parallel relation to
the first and second vertical members, respectively, wherein the
first and second vertical members are configured to move vertically
with respect to the third and fourth vertical members,
respectively.
13. The autonomous robot of claim 1, further comprising a compound
linear actuator for imparting horizontal movement to the first and
second arms substantially beyond a width of the robot, wherein the
width of the robot is defined by the width of the cross-member.
14. A method of loading a cargo container with cargo, the method
comprising the steps of: providing an autonomous robot configured
for movement into and out of the cargo container, wherein the robot
includes a first arm and a second arm, environment sensing
hardware, and a conveyor; positioning the robot within the cargo
container; placing the cargo on the conveyor and conveying the
cargo toward the first and second arms via the conveyor; moving the
first and second arms to a first position such that the first and
second arms are adjacent to the cargo on opposing sides thereof;
applying a suitable holding pressure on the cargo by the first and
second arms; detecting one or more edges of existing cargo within
the container to determine an offload space sized to accommodate
the cargo; selecting an offload coordinate within the offload
space; moving the first and second arms to a second position,
wherein the second position corresponds to the offload coordinate,
whereby the cargo is moved from the conveyor into the offload
space; and reducing the holding pressure applied to the cargo by
the first and second arms, whereby the cargo is released into the
offload space.
15. The method of claim 14, further comprising the step of
imparting forward motion to the robot until a sensor situated on at
least one of the first and second arms senses a predetermined
amount of pressure exerted thereon.
16. The method of claim 14, further comprising the step of reducing
the size of a space between the cargo and existing cargo by using
either the first arm or the second arm to push a side of the cargo
opposite the existing cargo toward the existing cargo.
17. A method of unloading a cargo container with cargo, the method
comprising the steps of: providing an autonomous robot configured
for movement into and out of the cargo container, wherein the robot
includes a first arm and a second arm, environment sensing
hardware, and a conveyor; determining the location of the cargo by
detecting one or more edges thereof utilizing the environment
sensing hardware; moving the first and second arms to a first
position such that the first and second arms are adjacent to the
cargo on opposing sides thereof; applying a suitable holding
pressure on the cargo by the first and second arms; moving the
first and second arms to a second position, wherein the second
position is defined as an area situated near the conveyor; and
reducing the holding pressure applied to the cargo by the first and
second arms, whereby the cargo is conveyed away from the first and
second arms via the conveyor.
18. The method of claim 17, further comprising the step of: moving
the cargo from a skewed position to a position conducive for
grasping by the first and second arms by utilizing either the first
or second arms to push against a front face of the cargo, a side of
the cargo, or a combination thereof.
19. An autonomous robot for loading and unloading cargo of a cargo
container, wherein the robot is comprised of: means for grasping
the cargo and transferring the cargo from a pick-up point to a
drop-off point; means for detecting cargo within the cargo
container; means for detecting at least one of a wall and a ceiling
of the container; means for imparting motive force to the robot;
and a processing unit configured to control directional movement,
loading, and unloading routines of the robot.
20. The autonomous robot of claim 19, wherein the means for
detecting the cargo, walls, and ceiling is a multi-element or
single-element detector configured to detect energy within the
electromagnetic spectrum.
21. The autonomous robot of claim 19, wherein the means for
imparting motive force to the robot include at least one of: a
retractable foot; one or more treads; or a plurality of wheels.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is directed to an autonomous robot
and, more specifically, to a robot for loading and unloading cargo
into and out of cargo containers.
[0003] 2. Description of Related Art
[0004] Shipping containers are provided in standardized sizes in
order to facilitate transport at all international ports. Bulk
merchandise is normally packaged within cartons, cardboard boxes,
or other substantially rectilinear packages. Depending upon the
merchandise, the cartons may be plastic-wrapped in order to further
contain and protect the contents. The cartons may also vary in size
within a single shipping container due to transportation of perhaps
dissimilar goods within the same shipping container.
[0005] Sea-going shipping containers used for international
transport of bulk merchandise rarely employ pallets. Although the
use of pallets would aid the loading and unloading of such
containers, dedicating space and weight to the pallets is not
customary due to the fact that space and weight are at a premium.
Specifically, the more cargo that is stored within the container,
the more cost-efficient the transit of that container becomes.
Therefore, most containers are close-packed including only the
merchandise, from wall to wall and floor to ceiling of the
container.
[0006] A number of different methods have been proposed to
accomplish unloading of the container. For example, one such method
includes shaking the contents of the container out between
guideposts down a chute. Obviously, such an approach is only
appropriate for the unloading of non-fragile merchandise.
Furthermore, this approach does not provide for the end transport
of the individual merchandise to stocking inventory or splitting up
a given shipment for further distribution to multiple destinations.
In any case, no automated process of efficiently loading a
container has yet been heretofore devised.
[0007] It is, therefore, desirable to overcome the above problems
and others by providing a system and method for efficient
autonomous loading and unloading of bulk merchandise from cargo
containers. Generally, such a system should operate in a timely and
cost-effective manner and account for space and weight constraints
imposed by the merchandise and the container.
SUMMARY OF THE INVENTION
[0008] Accordingly, we have invented an autonomous robot for
loading and unloading cargo of a cargo container. Cargo may
include, but is not limited to, one or more cartons, packages, or
boxes. Thus, the robot of the present invention is configured to
load and unload cargo having various and different physical
characteristics.
[0009] In a desirable embodiment, the robot includes a first
vertical member; a second vertical member spaced in substantially
parallel relation to the first vertical member; and a cross-member
secured to the first and second vertical members in a substantially
perpendicular orientation thereto. The robot further includes a
first arm and a second arm secured to the cross-member and
extending in a forward direction with respect to the robot. The
first and second arms may be non-articulated, articulated,
rotatable, or a combination thereof. Additionally, each arm may be
configured to move independently of the other arm. At least one of
the first and second arms include a pressure sensor for conveying
pressure data relating to an amount of pressure applied to the
cargo. Means, such as a retractable foot, one or more treads, or a
plurality of wheels, are utilized for imparting motive force to the
robot. A plurality of cameras are secured to the robot to provide a
field of vision for the robot.
[0010] Optionally, the robot may include a conveyor extending in a
rearward direction from the robot. The conveyor includes a loading
shelf adapted to receive cargo from the first and second arms of
the conveyor, wherein the loading shelf is situated such that in a
first position, vertical travel of the cross-member is obstructed
by the shelf, and such that in a second position, vertical travel
of the cross-member along the length of the first and second
vertical members is unobstructed.
[0011] The robot also includes means for imparting vertical
movement to the cross-member along the length of the first and
second vertical members and means for imparting horizontal movement
to the first and second arms along the length of the cross-member.
The means include, but are not limited to a linear actuator, a
pulley, a belt drive, or an expanding member.
[0012] A processing unit is configured to control directional
movement, loading, and unloading routines of the robot. The
processing unit is configured to detect the size of the cargo;
detect an edge of the cargo; detect a wall, ceiling, or floor of
the cargo container; detect shifted cargo and position thereof;
create loading and unloading strategies based upon the size of the
cargo; optimize the loading and unloading strategies during the
course of loading and unloading, respectively; conduct self-tests
to ensure operational functionality of the robot; receive external
queries; and/or detect unanticipated movement within a predefined
perimeter.
[0013] In an alternative embodiment, the robot further includes a
third and fourth vertical member secured in substantial parallel
relation to the first and second vertical member, respectively,
wherein the first and second vertical members are configured to
move vertically with respect to the third and fourth vertical
members, respectively. In still another alternative embodiment, the
autonomous robot may include a compound linear actuator for
imparting horizontal movement to the first and second arms
substantially beyond a width of the robot, wherein the width of the
robot is defined by the width of the cross-member.
[0014] A method for loading and unloading a cargo container with
cargo is also disclosed. Generally, loading the cargo container
includes the steps of providing an autonomous robot configured for
movement into and out of the cargo container, wherein the robot
includes a first arm and a second arm, a plurality of cameras, and
a conveyor; positioning the robot within the cargo container; and
placing the cargo on the conveyor and conveying the cargo toward
the first and second arms via the conveyor. The first and second
arms are configured to move to a first position such that the first
and second arms are adjacent to the cargo on opposing sides
thereof. Suitable holding pressure is applied to the cargo by the
first and second arms. Thereafter, the presence of one or more
edges of existing cargo within the container are detected to
determine an offload space sized to accommodate the cargo. An
offload coordinate is then selected within the offload space. The
offload coordinate is determined as a triangulation function
utilizing at least a first and second pixel from a first and second
video frame of a first and second respective camera selected from
the plurality of cameras. The first and second arms are moved to a
second position, wherein the second position corresponds to the
offload coordinate. Accordingly, the cargo is moved from the
conveyor into the offload space. Finally, the holding pressure
applied to the cargo by the first and second arms is reduced to
cause the cargo to be released into the offload space.
[0015] Generally, unloading the cargo container includes the steps
of providing an autonomous robot configured for movement into and
out of the cargo container, wherein the robot includes a first arm
and a second arm, a plurality of cameras, and a conveyor;
determining the location of the cargo by detecting one or more
edges thereof utilizing one or more of the cameras; and moving the
first and second arms to a first position such that the first and
second arms are adjacent to the cargo on opposing sides thereof.
Suitable holding pressure is then applied on the cargo by the first
and second arms. The first and second arms are moved to a second
position, wherein the second position is defined as an area
situated near the conveyor. Finally, the holding pressure applied
to the cargo by the first and second arms is reduced to cause the
cargo to be released and conveyed away from the first and second
arms via the conveyor. The robot is configured to move the cargo
from a skewed position to a position conducive for grasping by the
first and second arms by utilizing either the first or second arms
to push against a front face of the cargo, a side of the cargo, or
a combination thereof.
[0016] The robot of the present invention is deemed to operate
autonomously in the sense that there is a complete lack of human
intervention or support once a given container has been identified
for loading or unloading purposes. Furthermore, the robot may be
integrated into an automated inventory conveyor having put-and-pick
functionality that permits the development of a completely
automatic warehouse and distribution center.
[0017] Still other desirable features of the invention will become
apparent to those of ordinary skill in the art upon reading and
understanding the following detailed description, taken with the
accompanying drawings, wherein like reference numerals represent
like elements throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a front perspective view of a robot for loading
and unloading cargo;
[0019] FIG. 2 is a perspective exploded view of the robot of FIG.
1;
[0020] FIG. 3a is a perspective view of a first embodiment gripper
assembly of the robot;
[0021] FIG. 3b is a perspective view of a second embodiment gripper
assembly of the robot;
[0022] FIG. 3c is a perspective view of a third embodiment gripper
assembly of the robot;
[0023] FIG. 4a is a perspective view of a first embodiment for
imparting motive force to the robot;
[0024] FIG. 4b is a perspective view of a second embodiment for
imparting motive force to the robot;
[0025] FIG. 4c is a perspective view of a third embodiment for
imparting motive force to the robot;
[0026] FIG. 5 is a perspective view of a compound linear actuator
for imparting horizontal movement to the gripper assembly;
[0027] FIG. 6 is a perspective view of a compound linear actuator
for imparting vertical movement to the gripper assembly; and
[0028] FIG. 7 is perspective view of an exemplary cargo container
with cargo situated therein.
DETAILED DESCRIPTION OF THE INVENTION
[0029] For purposes of the description hereinafter, spatial or
directional terms shall relate to the invention as it is oriented
in the drawing figures. However, it is to be understood that the
invention may assume various alternative variations, except where
expressly specified to the contrary. It is also to be understood
that the specific apparatus illustrated in the attached drawings,
and described in the following specification, are simply exemplary
embodiments of the invention. Hence, specific dimensions and other
physical characteristics related to the embodiments disclosed
herein are not to be considered as limiting.
[0030] FIGS. 1 and 2 depict an autonomous robot 10 configured to
load cargo into and unload cargo out of a cargo container.
Generally, robot 10 includes a first vertical member 12 spaced in a
substantially parallel relation to a second vertical member 14. A
cross-member 16 is secured to first and second vertical members 12,
14 in a substantially perpendicular orientation thereto. A first
arm 18 and a second arm 19 are secured to cross-member 16 and
extend in a forward direction with respect to robot 10. The
cross-member 16 in combination with first and second arms 18, 19
are referred to herein as a gripper assembly 20 of robot 10.
Accordingly, this aspect of robot 10 assumes a framework design,
which may be structurally strengthened via additional supports,
such as support 22. The structural components of robot 10 may be
constructed of any suitable material adapted to withstand stresses
associated with loading and unloading operations of robot 10. The
material type, gauge, and reinforcement used in construction of
robot 10 may be defined by the greatest anticipated forces (e.g.,
torque) in addition to a safety multiplier. Exemplary materials
that may be utilized include, but are not limited to a titanium
alloy and an extruded aluminum alloy.
[0031] Webster's II New College Dictionary, Copyright 2001 by
Houghton Mifflin Company, defines "robot" as "a machine or device
that works automatically or by remote control." Accordingly, the
term "robot" in the context of the present application should be
given a broad interpretation to encompass any mechanical device
configured to autonomously load and unload cargo from a cargo
container. Furthermore, it is to be understood that robot 10
discussed herein is only an exemplary embodiment robot and,
therefore, the design of a robot suitable for autonomously loading
and unloading cargo from a cargo container is not to be construed
as limited by the description or drawings provided herein.
[0032] Robot 10 is configured to allow for a wide range of vertical
and horizontal movement of first and second arms 18, 19.
Specifically, vertical movement of the first and second arms 18, 19
is effected by moving gripper assembly 20 the length of first and
second vertical members 12, 14. First and second vertical members
12, 14 may incorporate a linear actuator, pulley/belt drive,
expanding/telescoping member motor driven system, or any other
suitable drive mechanism for imparting vertical movement to gripper
assembly 20. Thus, it is to be understood that gripper assembly 20
is movably secured to first and second vertical members 12, 14. For
example, as shown in FIG. 2, a respective actuator 24 may be
integrated within first and second vertical members 12, 14 for
vertical travel therein. Portions of actuators 24 extending from
first and second vertical members 12, 14 may be connected to
respective opposing ends of cross-member 16. The aforementioned
drive mechanisms are for exemplary purposes only and are not to be
construed as limiting the invention. Additionally, the drive
mechanism may be powered by a driver, such as, without limitation,
one or more electric motors, such as a servo motor or a digital
step motor; pneumatics; hydraulics; and magnetic induction (e.g.,
focused or localized electromagnetic fields). Furthermore, it is to
be understood that the aforementioned drive mechanism and driver
may be associated with either one or both of vertical members 12,
14. However, desirably, each vertical member 12, 14 includes a
respective drive mechanism to allow for sufficient lifting power
and smooth and consi stent vertical travel of gripper assembly 20.
Each drive mechanism may be operated dependently or independently
of each other.
[0033] Desirably, horizontal movement of first and second arms 18,
19 is effected by a separate drive mechanism integrated within
cross-member 16. Thus, a drive mechanism similar to the
aforementioned drive mechanism and corresponding driver may be
utilized in connection with first and second arms 18, 19. For
example, as shown in FIG. 2, respective actuators 26, such as
pulleys, may be integrated within cross-member 16. A pulling action
of respective belts secured to first and second arms 18, 19 causes
first and second arms 18, 19 to move along the length of the
cross-member as well as move away and towards each other. It is to
be understood that first and second arms 18, 19 may be configured
to move independently of each other. Thus, in connection with the
vertical movement provided by actuator 24 of first and second
vertical. members 12, 14, first and second arms 18, 19 are
configured to engage and disengage cargo at various positional
locations with respect to the framework of robot 10. The loading
and unloading process is optimized by minimizing mechanical
contraction and expansion between first and second arms 18, 19. For
example, a small contraction (i.e., reduction in distance between
two arms 18, 19) serves to grasp the cargo, whereas a small
expansion (i.e., increase in distance between two arms 18, 19) will
release the cargo. Minimizing travel required by arms 18, 19
results in a reduction of load and/or unload time and mechanical
wear on robot 10.
[0034] With reference to FIGS. 3a-c, and with continuing reference
to FIGS. 1 and 2, a first embodiment gripper assembly 30, a second
embodiment gripper assembly 32, and a third embodiment gripper
assembly 34 are shown, respectively. Robot 10 depicted in FIG. 2 is
shown to utilize first embodiment gripper assembly 30; however, it
is to be understood that robot 10 may utilize any other type of
suitable gripper assembly including, but not limited to second or
third embodiment gripper assemblies 32, 34. Desirably, first
embodiment gripper assembly 30, first and second arms 18, 19 are
embodied as L-shaped members conducive to lifting a box from an
underside thereof as well as applying pressure to opposing sides of
the box. First and second arms 18, 19 may also be tapered or have a
wedge-shape to assist in entering spaces between boxes. First and
second arms 18, 19 may also include other attachments or ends that
may be more conducive for particular applications, such as lifting
variously sized or dimensioned objects. First embodiment gripper
assembly 30 includes first and second arms 18, 19 and dual
actuators 26 in the form of pulleys.
[0035] In contrast, first and second arms 18, 19 of second
embodiment gripper assembly 32 are embodied as horizontally
articulated arms. Arms 18, 19 are configured to rotate along a
vertical axis of each articulation point, as indicated by the
arrows. Each section of first and second arms 18, 19 may be
independently operated utilizing actuators 36. Furthermore, second
embodiment gripper assembly 32 utilizes only a single actuator 26.
Accordingly, first and second arms 18, 19 may be connected to each
other such that first and second arms 18, 19 move in tandem with
each other along the length of cross-member 16. Thus, instead of
utilizing independent arm movement, the gripping distance between
first and second arms 18, 19 may be changed via the articulation
functionality inherent in first and second arms 18, 19. Third
embodiment gripper assembly 34 utilizes two actuators 26 in
combination with rotational articulated arms 18, 19. Arms 18, 19
are configured to rotate along a horizontal axis of each
articulation point, as indicated by the arrows. Still another
alternative embodiment may utilize fully articulated arms, such
that first and second arms 18, 19 provide both horizontal and
vertical articulation. Accordingly, it is to be understood that the
first and second arms 18, 19 of the first, second, and third
embodiment gripper assembly 30, 32, 34 may be embodied in an
unlimited number of ways and may be used to hold cargo other than
boxes or other rectilinear objects. Robot 10 may be configured to
handle any three-dimensional object, securing the object either
through direct physical contact with the object or through indirect
means (e.g., through manipulation of electromagnetic fields).
Exemplary object shapes include, but are not limited to cylindrical
canisters, triangular or rhombohedral-shaped boxes, spheroids, as
well as other less common or uniquely shaped objects. Thus, it is
to be understood that robot 10 is not limited in the shapes and
sizes of objects that may be loaded and unloaded.
[0036] Desirably, one or both of first and second arms 18, 19 of
first, second, and/or third embodiment gripper assemblies 30, 32,
34 include a sensor, such as a pressure sensor 37 and/or an edge
sensor 38. Pressure sensor 37 may be used to detect an amount of
pressure applied to the box by first and second arms 18, 19. Edge
sensor 38 mounted at a tip of each of first and second arms 18, 19
may be used to detect the far edge of a box such that robot 10 is
aware of the depth of that box. As shown, gripper assembly 20 may
be constructed in a variety of ways, with the specific structural
design of gripper assembly 20 dictated by the application of robot
10. For example, a specific structural design of gripper assembly
20 may be utilized for increased cargo dimensions and increased
load weight applications.
[0037] Returning to FIG. 2, robot 10 includes an appropriate
mechanism for imparting motive force to robot 10. Generally, the
motive force provides varying degrees of movement of robot 10 with
respect to the operating environment. For example, movement may be
in forward, rearward, and turning directions to effect loading and
unloading of cargo from a container. Specifically, the motive force
allows robot 10 to acquire a given target container from a loading
ramp or home docking position and then move to an appropriate
initial load or unload position inside or at a tailgate portion of
a container. In the desirable embodiment, first and second vertical
members 12, 14 are secured to respective drive members 39. Drive
members 39 may be integral with or secured to first and second
vertical members 12, 14. Desirably, drive members 39 are spaced in
substantial parallel relation to each other.
[0038] With reference to FIGS. 4a-c, and with continuing reference
to FIGS. 1 and 2, a first embodiment drive member 40, a second
embodiment drive member 42, and a third embodiment drive member 44
are shown, respectively. Robot 10 depicted in FIG. 2 is shown to
utilize first embodiment drive member 40, however, it is to be
understood that robot 10 may utilize any other type of suitable
drive member including, but not limited to, second or third
embodiment gripper assemblies 42, 44. First embodiment drive member
40 includes a body 46 supporting a foot 48 adapted for travel along
the length of body 46. Foot 48 is connected to a belt 50 driven by
an actuator 52. A plurality of casters 55 may be attached to body
46 to provide balanced support to robot 10. Desirably, in
operation, foot 48 applies pressure to a floor surface using loaded
springs. To move robot 10 forward, foot 48 is first retracted using
a solenoid 54. Then, actuator 52 is engaged to move belt 50, and
effectively foot 48, forward. Once foot 48 has moved a predefined
distance along the length of body 46, solenoid 54 is released and
foot 48 again applies pressure to the floor surface. The final
movement is achieved by activating actuator 52 again and reversing
the direction of belt 50. This effectively causes robot 10 to crawl
forward. Reversing the movement of actuator 52 causes the robot 10
to crawl backwards. Desirably, to obtain fluid and linear forward
or backward motion of robot 10, the respective drive members 39 are
operated in tandem. However, engaging only one driver member 39,
engaging each of drive members 39 at different rates, or engaging
each of the drive members in opposite directions in relation to
each other causes robot 10 to turn. Second embodiment drive member
42 may include a tread mechanism 56 having a plurality of wheels 58
engaging a continuous belt 60, similar to that of a tank or tractor
tread mechanism. Continuous belt 60 may be constructed of a
friction-inducing coating that grips the floor surface upon
movement of robot 10. Third embodiment drive member 44 may include
a wheel-based mechanism 62 including a plurality of wheels 64 that
may be independently driven by respective servo motors.
[0039] Returning to FIGS. 1 and 2, robot 10 may also include a
conveyor 66, desirably situated between first and second vertical
members 12, 14 and extending in a rearward direction from robot 10.
Conveyor 66 may include a series of rollers 68 to effect forward
and backward movement of cargo placed on conveyor 66. It is to be
understood that rollers 68 are not to limit the scope of the
conveyor, as the conveyor may instead, or in combination therewith,
include a belt or other suitable conveying component.
[0040] Desirably, conveyor 66 also includes a loading shelf 70
situated at the end of conveyor 66 proximal to the robot 10.
Specifically, loading shelf 70 is positioned such that cargo may be
removed from or transferred to loading shelf 70 by first and second
arms 18, 19. Loading shelf 70 may employ conveying components
including, but not limited to, rollers or a belt. Furthermore,
loading shelf 70 is adapted to move out of the way, such as by
folding or sliding, when no cargo is situated thereon. An arrow 71
indicates an exemplary direction of downward folding by the loading
shelf 70. Thus, loading shelf 70 does not interfere with movement
of the cross-member along the length of first and second vertical
members 12, 14 when loading and unloading cargo from a container.
For example, when receiving cargo from conveyor 66, loading shelf
70 is situated in a first position, such that first and second arms
18, 19 are able to grasp the cargo. In this first position,
vertical travel of first and second arms past the shelf is
obstructed. After the cargo is securely grasped by first and second
arms 18, 19, loading shelf 70 moves to a second position. In this
second position, vertical travel of first and second arms 18, 19 is
unobstructed and the cargo may be effectively moved the full length
of first and second vertical members 12, 14. During the process of
unloading cargo from a container, loading shelf 70 moves from the
second position to the first position at an appropriate time when
first and second arms 18, 19 are in position to release the cargo.
Thus, the cargo is released onto loading shelf 70 to be conveyed
via conveyor 66 away from robot 10.
[0041] Desirably, conveyor 66 may be relatively fixedly secured to
robot 10 such that conveyor 66 moves concurrently with robot 10,
especially into and out of a container. Conveyor 66 may include
casters 69 to assist in movement along the floor surface. In an
alternative embodiment, conveyor 66 need not be fixedly secured to
robot 10. Rather, conveyor 66 may be situated in an area remote
from robot 10, for example, extending from a warehouse adjacent to
a loading dock. Robot 10 then travels to and from the remotely
situated conveyor to load and unload cargo. Because conveyor 66 is
not fixedly secured to robot 10 and no movement limitations are
imposed on first and second arms 18, 19 by loading shelf 70,
conveyor 66 need not utilize loading shelf 70 in this alternative
embodiment.
[0042] Robot 10 may also include environment sensing hardware.
Environment sensing is not limited to the electromagnetic spectrum
(e.g., gamma-rays, x-rays, ultraviolet rays, visible light,
infrared radiation, radio-frequency, and sound waves), but also to
the detection of material type and phase (e.g., liquid, solid, gas)
whose classification in turn may also be based upon the
electromagnetic spectrum. An example of environment sensing
hardware is a plurality of cameras 72, mounted to various portions
of the robot 10, such as first and second vertical members 12, 14,
support 22, and/or gripper assembly 20. Cameras 72 are capable of
but not necessarily limited to detecting photons whose energies may
coincide with the portion of the electromagnetic spectrum normally
detectable by human sight (i.e., the "visible" spectrum). Thus,
each of cameras 72 may be embodied as a multi-element passive
photon detector. Desirably, cameras 72 are positioned to capture
still images or video representative of an expansive field of
vision, including a stereoscopic view, relating to the load and
unload operations of robot 10. Additionally, robot 10 may support
other environment sensing and translating hardware including, but
not limited to multi-element or single element sound transducers,
multi-element or single element thermal sensors, multi-element or
single element passive radio-frequency sensors, multi-element or
single element active radio-frequency transducers, and a gas/liquid
sampling sensors.
[0043] Robot 10 includes a processing unit 75 configured to control
loading and unloading routines and associated directional movement
relating to the operation of robot 10. Processing unit 75 may be
embodied as software driven computing hardware having suitable
input and output connections that communicatively connect sensors,
actuators, and other components with processing unit 75. These
connections for implementing communicative connectivity between
processing unit 75 and various components of robot 10 are not
explicitly discussed or shown herein, as they are to be understood
by persons having ordinary skill in the art.
[0044] Processing unit 75 is configured to control a wide range of
functions inherent in the operation of robot 10. For example,
processing unit 75 includes appropriate algorithms for creating and
implementing loading and unloading strategies. Processing unit 75
is configured to continually optimize loading and unloading
strategies. Specifically, processing unit 75 updates height, depth,
weight, and load/unload time per item and determines in real time
whether or not a revision to the current load/unload strategy is
required. Processing unit 75 is configured to receive inputs from
actuators 24, 26, sensors 37, 38, and cameras 72 to continually
sense the operating environment and detect changes thereto. For
example, based upon the type of cargo to be loaded or unloaded,
processing unit 75 may include specific pressure constraints, that
once sensed by pressure sensor 37, indicate to processing unit 75
to cease or reduce any further contraction between first and second
arms 18, 19 on the cargo.
[0045] Furthermore, processing unit 75, via appropriate environment
sensing and translating hardware is configured to detect the size
of the cargo; detect edges of the cargo; detect the presence of
shifted cargo and the position thereof; and detect the wall,
ceiling, or floor of the cargo container. The cargo, wall, ceiling,
or floor may be detected by a multi-element or single-element
detector configured to detect energy within the electromagnetic
spectrum. If there in insufficient energy generated or redirected
by the cargo, walls, ceiling, and/or floor at a particular point in
the electromagnetic spectrum, then robot 10 may be further
augmented with a device for generating energy over the portion of
the electromagnetic spectrum, again for the purpose of detecting
the cargo, walls, ceiling, and/or floor.
[0046] Processing unit 75 may also include self-tests to ensure
operational functionality of all sensors and servos. For example,
processing unit 75 may be configured to recalibrate the sensors in
real time and a servo interface may be monitored through feedback
loops to the servo drivers internal to processing unit 75.
Processing unit 75 may also anticipate possible or impending
failures by monitoring servo actuator current draw, for example.
Furthermore, processing unit 75 may be responsive to external
queries, such as wirelessly transmitted commands, issued thereto
even during the course of loading or unloading. Robot 10 may also
be configured to ensure safe operation thereof. For example, should
unanticipated movement (e.g., cargo or personnel) be detected
within a predefined safety perimeter, processing unit 75 may
instruct robot 10 to cease loading and unloading operations and
issue an alert through an annunciator.
[0047] Desirably, the width of robot 10 is sized to accommodate the
interior width of a container. Specifically, first arm 18 is
adapted to move along cross-member 16 to a point adjacent to one
side wall of the interior of the container, whereas second arm 19
is adapted to move along cross-member 16 to a point adjacent to the
opposing side wall of the interior of the container. Similarly,
movement of gripper assembly 20 ranges from the floor to the
ceiling of the container. Thus, the presently described robot 10
need not rely on lateral movement of robot 10 once inside the
container. However, this specific design of robot 10 limits
efficient use of robot 10 to containers having similar widths and
heights as those widths and heights that are accessible via the
range of movements of first and second arms 18, 19. Thus, it is
desirable to provide modifications to robot 10 to allow extended
expansion or contraction in height or width, as necessary, to
accommodate a range of various container sizes.
[0048] With reference to FIGS. 5 and 6, and with continuing
reference to FIGS. 1 and 2, a compound linear actuator member 77
for imparting horizontal movement and a compound linear actuator
member 78 for imparting vertical movement are shown, respectively.
Accordingly, without manual intervention or modification, robot 10
is adapted to automatically scale itself, through expansion and
contraction of compound linear actuator members 77, 78 in width and
height, respectively, to handle a range of container sizes.
Compound linear actuator member 77 is similar in construction to
gripper assembly 20 except for the addition of a second
cross-member 80 that is movably secured thereto. Specifically,
second cross-member 80 includes one or more actuators 82 that allow
gripper assembly 20 to controllably move horizontally in a parallel
relation to second cross-member 80. Thus, unlike the previously
discussed embodiments of gripper assembly 20, second cross-member
80, not cross-member 16, is directly secured to first and second
vertical member 12, 14 of the robot 10.
[0049] Compound linear actuator member 78 is similar in
construction to the framework design defined by first and second
vertical members 12, 14 and support 22. However, cross-member 20 is
secured to secondary first and second vertical members 84, 86. One
or more actuators 88 may be integrated within secondary first and
second vertical members 84, 86 for vertical travel therein.
Portions of actuators 88 extending from secondary first and second
vertical members 84, 86 may be connected to respective opposing
ends of the cross-member 16. Secondary first and second vertical
members 84, 86 may then be movably secured to the respective
actuators 24 of the first and second vertical members 12, 14.
Linear actuator member 78 allows secondary first and second
vertical members 84, 86 to controllably move vertically in a
parallel relation to first and second vertical members 12, 14.
[0050] Accordingly, linear actuator members 77, 78 are designed
such that when retracted, the overall width or height of linear
actuator members 77, 78 is minimized; whereas, when extended the
overall width or height of linear actuator members 77, 78 is
maximized. It is to be understood that the aforementioned linear
actuators 77, 78 are depicted as exemplary embodiments of
mechanisms for extending the reach of first and second arms 18, 19.
Thus, other functionally equivalent mechanisms may be employed in
connection with robot 10. Furthermore, it is to be understood that
gripper assembly 20 may be designed such that the aforementioned
linear actuator members 77, 78 are unnecessary. For example, most
shipping containers have a standard width and height with such
dimensions varying by only a few inches. Therefore, the cost and
complexity of robot 10 may be reduced by implementing minor
extension mechanisms as compared to implementing linear actuator
members 77, 78.
[0051] With reference to FIG. 7, and with continuing reference to
FIGS. 1 and 2, the operation of robot 10 will now be discussed. To
facilitate the discussion of the present invention with respect to
loading and unloading functionality, FIG. 7 depicts a Cartesian
coordinate system overlaid onto an exemplary shipping or cargo
container 90. As is known in the art, cargo containers exist in
various sizes. For example, a "20 foot" cargo container has a
length (depth) of 19'5'', a width of 92'', and a height of 92''. In
contrast, a "45 foot high cube" cargo container has a length of
44', a width of 92'' and a height of between 102-106''. It is to be
understood that robot 10 may be utilized in connection with all
forms of shipping containers or cargo transportation mediums. For
example, robot 10 may be used to load and unload cargo from an area
not bounded by walls or a ceiling (e.g., pallet-based cargo). Thus,
the term "cargo container" may be construed to embody wall/ceiling
bounded and wall/ceiling unbounded containers.
[0052] As shown in FIG. 7, the x-axis parallels the width of
container 90, the y-axis relates to the height of container 90, and
the z-axis measures distance into container 90 from access doors
92, a hatch, or opening of container 90. For convenience, the
origin of the Cartesian coordinate system is chosen along the
centerline of container 90 such that z=0 defines the position of
the doors 92. Thus, a person situated at the origin, facing in the
direction of the positive z-axis, would then observe a negative
x-axis value as corresponding to their left-hand side and a
positive x-axis to their right-hand side. Moving further into
container 90 would correspond to an increasing z-axis value.
Raising or lowering the person's hands would then correspond to a
relative increase or decrease in the value of the y-axis
coordinate, respectively.
[0053] The functionality of robot 10 will now be discussed with
regard to two basic exemplary operational scenarios, namely the
loading and unloading of cartons 94 from container 90. In the load
scenario, the goal is to load container 90 with cargo, such as bulk
merchandise contained within cartons, cardboard boxes, or other
substantially rectilinear packages. However, it is to be understood
that the cargo may include merchandise of various proportions and
non-rectilinear dimensions. The cartons may be constructed of any
rigid or semi-rigid material including, but not limited to
cardboard, wood, plastic or metal.
[0054] With reference to FIG. 7, robot 10 may be positioned into
open container 90 at the mid-point thereof (in x) such that a
most-forward portion of gripper assembly 20 is placed as far
forward (in z) into container 90, purposefully leaving room in
depth (z) for building a wall of cartons 94 in the x-y plane. This
position of robot 10 defines the start point for the loading of
cargo. First carton 94 is placed on conveyor 66, travels along the
length thereof, and eventually stops at loading shelf 70. Carton 94
is sensed by robot 10 that it is in a position waiting to be
loaded. Directed by processing unit 75, first and second arms 18,
19 approach carton 94 from opposite sides thereof. Sensing
immediate contact with the opposing sides of the carton 94
independently, each arm 18, 19 initially halts until both arms 18,
19 are in position for a final grab. At this point, carton 94 is
grasped by reducing the distance between first and second arms 18,
19 until a specific holding pressure is achieved, as detected by
one or more pressure sensors 37. The holding pressure may be
predetermined, but may be automatically adjusted to compensate for
carton gross weight, carton width and the resulting distribution of
interior load over carton width. Once proper holding pressure is
achieved, loading shelf 70 may be moved out of the way. Carton 94
is then moved in one or both of the x and y directions to a
designated Cartesian coordinate, suitable for anticipating offload
of carton 94. That coordinate is determined by the stereoscopic
vision of robot 10 in connection with edge detection algorithms and
triangulation calculations.
[0055] In an exemplary embodiment, stereo imaging is accomplished
in a single snapshot utilizing two or more of cameras 72 over an
entire load/unload area. Each pixel of both camera snapshots
corresponds to a point in space that has reflected light towards
cameras 72. Pixel-defined portions of each of the snapshots vary in
illumination intensity with respect to each other. An edge detector
(embodied in software) is applied to the snapshots such that subtle
differences in lighting are detected based upon pixel intensity
statistics. Triangulation calculations allow every pixel in the
snapshots to be mapped in virtual space to a corresponding
real-life coordinate (x, y, z) on the overlaid Cartesian coordinate
system. Accordingly, processing unit 75 may determine empty spaces
and appropriate offload coordinates, the physical location of
existing cartons already in container 90, the walls of container
90, and the ceiling of container 90. It is to be understood that
the offload coordinate may be determined by use of a single camera
72, wherein the single camera is moved between frames.
[0056] It is to be understood that robot 10 may utilize other
hardware and vision system technologies to detect cargo and the
positioning thereof. Thus, the use of cameras 72 in connection with
edge detection hardware and software is discussed herein for
exemplary purposes only. Another exemplary and non-limiting cargo
detection technique may include template matching in connection
with visual input received from cameras 72. As is known in the art,
a template matching system attempts to match a captured image of an
object with a pre-defined virtual model of that real-life image
within a database. Upon finding a match, characteristics (e.g.,
dimensions, weight, etc.) of the real-life object are realized and
may be utilized when interacting with that real-life object. With
respect to the present invention, if robot 10 senses a particular
recognizable cargo, then robot 10 may implement the necessary
grasping routines to specifically handle that cargo.
[0057] After the appropriate offload coordinate has been determined
and gripper assembly 20 has moved carton 94 to a corresponding
location for offloading, robot 10, via motive force imparted by
drive member 39, moves carton 94 forward until a predetermined
maximum forward pressure against the most forward wall of container
90 is sensed by edge sensor 38 or other suitable sensor. Carton 94
is released by expanding the distance between first and second arms
18, 19 as gripper assembly 20 is simultaneously retracted in z.
Thereafter, gripper assembly 20 is raised to an elevation in y
above the level of conveyor 66, loading shelf 70 is placed back in
a receiving position, and first and second arms 18, 19 are
positioned in anticipation of the next carton. Any excess space
between cartons or between cartons and walls of container 90 may be
minimized by appropriately positioning gripper assembly 20 (in x, y
and z) to then slide any carton in the proper direction (in x) via
one of the arms, such as first arm 18. The sliding of the carton
may be stopped when the maximum pressure, as detected by one or
more pressure sensors 37, has been achieved against the neighboring
object or wall.
[0058] The aforementioned loading process may be repeated following
standard packing protocol until the loading process has been
completed, as defined by the amount of cartons to be loaded and/or
insufficient room for additional cartons. At the time each carton
94 is initially grasped by gripper assembly 20, the dimensions of
carton 94 may be determined using any appropriate sensors, as
previously discussed. Dimensional information will determine if
another row (aligned with the x-axis) of cartons needs to be
started, either on top (increasing y) or in front (decreasing z) of
the preceding row of cartons. With sufficient pre-information about
the dimensions and weight of the cartons, robot 10 is able to
create an optimum overall load strategy utilizing specialized
algorithms.
[0059] In an unload scenario, the goal is to unload container 90 of
some or all cartons contained therein. The basic functional
requirements required of robot 10 are quite similar to those of the
load scenario, and, in almost every aspect, are the reverse of the
load process. An additional aspect that robot 10 is configured to
contend with is shifted cargo. Specifically, neat rows and columns
of cartons formed during the load process may no longer exist after
transit of container 90. Thus, a portion of the various cargo may
be skewed in any of the axes (x, y, z). First, the position of the
skewed carton is determined by applying edge detection and
calculating the points in space corresponding to the skewed
carton's vertices. Next, a combination of x and z movements via the
first and/or second arms 18, 19 may be employed to reposition the
skewed carton into a position conducive for grasping during the
unload process. This process is similar to the pushing required to
obtain a close pack during the load process, except that it may
require judiciously selecting a particular point on the skewed
carton to initiate the push and then rapidly obtaining snapshots
and calculating in sequence in order to verify progress. At the
completion of the load or unload operation, robot 10 may
automatically return to a designated docking station.
[0060] As previously discussed, robot 10 discussed herein is only
an exemplary embodiment robot and, therefore, it is envisioned that
other robots may be implemented for autonomously loading and
unloading cargo from a cargo container. Thus, robot 10 of the
present invention is to be construed as including appropriate
controllers and sensors to detect cargo, walls, and/or a ceiling of
the container. Robot 10 also includes a mechanism designed for
grasping the cargo and transferring the cargo from a pick-up point
to a drop-off point and another mechanism for imparting motive
force to the robot. These mechanisms are adapted to impart a wide
range of motion, such as six degrees of freedom of motion, to the
robot. Appropriate hardware, such as a processing unit, and
software is configured to control the operational functions (e.g.,
directional movement, loading, and unloading routines) of robot
10.
[0061] The invention has been described with reference to the
desirable embodiments. Modifications and alterations will occur to
others upon reading and understanding the preceding detailed
description. It is intended that the invention be construed as
including all such modifications and alterations insofar as they
come within the scope of the appended claims or the equivalents
thereof.
* * * * *