U.S. patent application number 09/783834 was filed with the patent office on 2001-08-16 for adherent robot.
Invention is credited to Hopkins, Kathleen Garrubba.
Application Number | 20010013434 09/783834 |
Document ID | / |
Family ID | 24010184 |
Filed Date | 2001-08-16 |
United States Patent
Application |
20010013434 |
Kind Code |
A1 |
Hopkins, Kathleen Garrubba |
August 16, 2001 |
Adherent Robot
Abstract
A robot capable of moving against gravity uses at least one
vacuum cup assembly having means for applying a lubricant on the
working surface so the cup may slide on the surface as the robot is
maneuvered with the aid of powered wheels. The wheels and vacuum
cup assemblies are coordinated to move on varied surfaces. The
robot module may be equipped with various task-performing
assemblies, and may be employed in caravans, trains, or separately
in swarms. The vacuum cup assemblies include a pair of springs
working against each other to provide stability and flexibility at
the point of attachment to the body of the robot.
Inventors: |
Hopkins, Kathleen Garrubba;
(Pittsburgh, PA) |
Correspondence
Address: |
William L. Krayer
1771 Helen Drive
Pittsburgh
PA
15216
US
|
Family ID: |
24010184 |
Appl. No.: |
09/783834 |
Filed: |
February 14, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09783834 |
Feb 14, 2001 |
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09505409 |
Feb 16, 2000 |
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Current U.S.
Class: |
180/7.1 |
Current CPC
Class: |
B62D 57/024 20130101;
Y10S 180/901 20130101; B63B 71/00 20200101 |
Class at
Publication: |
180/7.1 |
International
Class: |
B62D 057/00 |
Claims
1. A vacuum cup assembly including a vacuum cup comprising a stem
member and a flexible, substantially conical body, a port in said
body for a vacuum source, at least two annular ridges projecting
downwardly from said body for intimately contacting a base surface,
and at least one port for introducing lubricant to an interface of
at least one of said ridges and the base surface.
2. A vacuum cup assembly of claim 1 including a filter in said
vacuum source port.
3. A vacuum cup assembly of claim 1 wherein said flexible body has
at least three annular ridges, said annular ridges being
substantially concentric.
4. A vacuum cup assembly of claim 1 mounted on a chassis including
means for attaching a task-performing device to said chassis.
5. A vacuum cup assembly of claim 4 including powered wheels for
moving said chassis.
6. A vacuum cup assembly of claim 5 wherein said wheels are powered
by motors on said vehicle and are capable of being independently
steered.
7. Method of manipulating a robot on a working surface comprising
drawing a vacuum on at least one vacuum cup having a flexible
surface for adhering to a working surface, feeding a lubricant to
said flexible surface to form a film between said flexible surface
and said working surface, and activating a locomotion means to
propel said robot in a desired direction.
8. Method of claim 7 wherein said locomotion means are wheels.
9. Method of claim 7 wherein the reaction force R.sub.SC of said
vacuum cup is determined at least partly by the relationship
R.sub.SC=p.sub.a(A.sub.o)-N-p.sub.v(A.sub.I) where R.sub.SC is the
reaction force, p.sub.v is the vacuum pressure applied to the
suction cup, p.sub.a is the atmospheric pressure acting on the
outside of the suction cup, A.sub.o is the outside area of the
suction cup, A.sub.I is the inside area of the suction cup, and N
is the normal force acting or load applied to the suction cup,
usually the vehicle weight.
10. A robot comprising at least one robot module comprising (a) a
locomotion section comprising locomotion means for moving said
module on a work surface, and (b) a slidable adherence section for
adhering said module to a work surface while said module is moving
thereon.
11. A robot of claim 10 wherein said locomotion section comprises
at least one wheel, a motor therefor, and means for steering said
wheel.
12. A robot of claim 10 wherein said slidable adherence section
comprises a vacuum cup having a top side and an underside, a
lubricant port therein, and a duct for delivering lubricant through
said duct to the underside of said vacuum cup.
13. A robot of claim 10 wherein said slidable adherence section
comprises a vacuum cup having a stem member, a flexible,
substantially conical body, a port in said body for a vacuum
source, at least two substantially concentric annular ridges
projecting downwardly therefrom for intimately contacting a base
surface, and at least one port for introducing lubricant to the
interface of at least one of said ridges and the base surface.
14. A robot of claim 10 including at least one spring for urging
said wheel toward said work surface.
15. A robot of claim 10 including a berth for a specific
task-performing device.
16. A robot of claim 10 including an antenna for receiving control
signals.
17. A robot of claim 10 including a flexible tube for connection to
a remote source of vacuum.
18. A robot of claim 10 including a flexible wire for connection to
a remote source of electric power.
19. A robot of claim 10 including a flexible tube for connection to
a remote source of lubricant.
20. A robot of claim 10 including a microprocessor for controlling
at least one function on said robot.
21. A robot comprising at least one robot module comprising (a) a
locomotion section comprising locomotion means for moving said
module on a work surface, (b) a robot body, and (c) a slidable
adherence section for adhering said module to a work surface while
said module is moving thereon, said slidable adherence section
including a pair of opposing springs for flexibly stabilizing the
distance of said robot body from a working surface.
22. A robot of claim 21 wherein said opposing springs are on
opposite sides of said robot body.
23. A robot of claim 21 wherein said slidable adherence section
comprises at least one vacuum cup.
24. A robot of claim 21 wherein said slidable adherence section
comprises at least two vacuum cups.
25. A robot of claim 22 including a stem on said vacuum cup for
holding a passage for a source of vacuum to said vacuum cup, said
springs are coil springs, and said stem passes through said
opposing springs.
26. A robot of claim 21 wherein said locomotion section comprises
at least one wheel turned by an electric motor.
27. A robot of claim 23 wherein said vacuum cup comprises a stem
member and a flexible, substantially conical body, a port in said
body for a vacuum source, at least two annular ridges projecting
downwardly from said body for intimately contacting a workpiece
surface, and at least one port for introducing lubricant to an
interface of at least one of said ridges and said workpiece
surface.
28. A robot of claim 23 wherein said stem member defines a vacuum
passage for providing vacuum to said vacuum cup.
29. A vacuum cup assembly for a robot having a robot body,
comprising a vacuum cup, a stem member thereon, said stem member
passing through at least a portion of said robot body, a lower stem
housing below said robot body portion, an upper stem housing above
said robot body portion, and springs within said upper and lower
stem housings for flexibly stabilizing said vacuum cup assembly
with respect to said robot body.
30. A vacuum cup assembly of claim 29 wherein said stem member
defines a passage from a source of vacuum to said vacuum cup.
31. A vacuum cup assembly of claim 29 wherein said vacuum cup
includes a port for feeding lubricant to said vacuum cup.
32. A vacuum cup assembly of claim 30 including a filter in said
passage.
33. A vacuum cup assembly of claim 29 wherein said springs are coil
springs and said stem passes through said springs.
Description
RELATED APPLICATION
[0001] This application is a continuation-in-part of copending
application Ser. No. 09/505,409 filed Feb. 16, 2000.
TECHNICAL FIELD
[0002] This invention relates to remotely controlled devices. The
remotely controlled devices are able to adhere to flat or curved
surfaces, including significantly inclined and even backwardly
leaning surfaces, and to maneuver on them to perform a variety of
tasks. The invention includes the use of specially designed vacuum
cups and a lubricant to facilitate sliding on the surface.
BACKGROUND OF THE INVENTION
[0003] Our invention is particularly designed to meet the needs of
the shipbuilding industry, in that our robots are adept at climbing
the sides of ships' hulls to inspect, clean (including scraping
and/or removing of barnacles and ocean scum), paint, and weld them
and to perform any other function one may wish to perform on a
ship's hull from a readily manipulable, adherent robot, even on a
very steep or even backwardly slanted surface. While my invention
is particularly good for performing such tasks on ships' hulls, it
may be used in any environment requiring such a remotely controlled
device, whether or not the surface tends to curve backwardly and
upwards. Various approaches have been proposed for accomplishing
such tasks. See, for example, Perego's U.S. Pat. No. 3,973,711,
describing a magnetic crawler for soldering.
[0004] It has been known to make and use remotely controlled
devices which adhere to a surface by vacuum. See, for example,
Lisec's U.S. Pat. No. 4,667,555 disclosing such a device for
cutting glass, the more versatile traveling device of Urakami
described in U.S. Pat. No. 4,926,957, and Ochiai's U.S. Pat. No.
4,785,902, showing suction cups which can be slightly tilted to
maneuver the device which carries them. The reader may also be
interested in U.S. Pat. Nos. 4,817,653, 5,293,887, and 4,828,059,
also generally within the field.
[0005] In U.S. Pat. No. 4,971,591, Raviv and Davidovitz propose a
"vehicle with vacuum traction" which facilitates the sliding of a
vacuum cup along a surface, while the vacuum is supporting a
certain amount of weight, either by using a low surface friction
material in the vacuum cup itself, particularly the rim portion, or
by placing a flexible sheet of low surface friction material under
the cup. One cannot rely on the low surface friction of such a
material for long, however, under industrial use conditions.
[0006] See also the device of Lange and Kerr described in U.S. Pat.
No. 5,890,250. They use a "grabber/slider vacuum cup" in a cleaning
system which sprays cleaning and rinsing liquids on the surface.
Wolfe et al, in U.S. Pat. No. 5,429,009, coordinate the movement
and activation of several vacuum cups to manipulate a robot on a
surface.
[0007] Such prior art machines and devices are generally not very
effective on rough or slimy surfaces. The art is in need of a
reliable, versatile robot capable of performing various tasks on
inhospitable and steeply inclined surfaces.
SUMMARY OF THE INVENTION
[0008] We have designed a robotic vehicle for use on steep inclines
and even upside down, which will maneuver and move easily over the
surface, and is capable of performing all sorts of tasks. The
vehicle preferably has at least one, but frequently a plurality of
vacuum cups, preferably specially designed as described herein,
including means for feeding lubricant to the surface, and
particularly to the surface occupied by the vacuum cup(s). Unlike
the Raviv et al patent discussed above, my system does not require
vacuum cup materials having low coefficients of friction, or a
sheet of low friction plastic interposed between the vehicle and
the surface, and is not unduly subject to wear.
[0009] Our invention includes one or more vacuum cups comprising a
flexible, (preferably shallow bell-shaped) body, a port therein for
a vacuum source, at least substantially annular ridge, preferably
two or more concentric ridges, projecting downwardly therefrom for
intimately contacting a base surface, and at least one port for
introducing lubricant to the interface of at least one of the
ridges and the base surface.
[0010] Our invention also includes a remotely controlled vehicle
including a chassis, at least one vacuum cup as described above,
and means for attaching a task-performing device to the chassis.
Movement is provided by independently powered wheels which may be
mounted separately or in modules together with the vacuum cups. The
chassis may be rigid or more or less articulated or hinged. If it
is articulated or hinged, the points of articulation or hinging may
be powered or not. As will be seen below, a boomerang shape is
preferred.
[0011] Our invention is useful not only for performing remote tasks
on the hulls of ships, but also for inspecting, cleaning and
painting, for example, domes, water towers, chemical plants and
reactors, storage tanks including large petroleum product storage
tanks, bridges and difficultly accessible surfaces on the inside
and outside of buildings and other structures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIGS. 1a, 1b, and 1c are side sectional views of our
preferred vacuum cup assembly, showing the effect of the
application of vacuum. FIGS. 1d, 1e, and 1f are expanded views of
portions of the vacuum cup as increasing vacuum is applied.
[0013] FIGS. 2a and 2b are underneath and sectional views of a
preferred form of our robot unit, showing placement of the vacuum
cup assemblies and wheel modules.
[0014] FIG. 3 is a side view of our robot in motion on a ship's
hull, performing the task of painting.
[0015] FIGS. 4a-4d represent a sequence of positions of a preferred
robot approaching a ship hull and beginning its ascent to a
position for use.
[0016] FIGS. 5a and 5b illustrate a vacuum cup assembly used in the
invention.
[0017] FIGS. 6 and 7 show caravans of robots for performing
sequential functions on a work surface.
[0018] FIG. 8 is a section of part of a preferred design of our
invention, in which opposiing compressed springs assure that the
vacuum cup assembly and the body of the robot maintain a stable
relationship.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring first to FIGS. 1a and 1d, the vacuum cup assembly
comprises a vacuum cup 1 made of a flexible, resilient material and
a tubular central stem 2 in which is mounted a filter 3. The outer
end 4 of stem 2 is adapted to be attached to a vacuum supply. On
the bottom of the vacuum cup 1 is a series of (preferably more than
one, as shown) concentric ridges 5, 6, 7, 8, and 9. Near the outer
edge of cup 1 is a port 10 for lubricant supply, adapted for
attachment to a tube or the like for supplying liquid lubricant to
the underside of the vacuum cup 1. In the initial stage of
application, lubricant is caused to flow, from a source not shown,
through port 10 into space 11 defined by outermost ridge 9 and the
edge 12 of the vacuum cup 1.
[0020] Vacuum may be applied before the beginning of lubricant flow
(preferably gradually if it is before) or after the flow begins.
Referring to FIGS. 1b and 1e, with the application of vacuum, the
vacuum cup 1 begins to flatten and adhere to the surface. As
lubricant continues to flow, it accumulates to a degree in space 11
and is drawn into the space between ridges 8 and 9, passing under
ridge 9. With the full application of vacuum as depicted in FIGS.
1c and 1f, lubricant is present in all the spaces 30. 31, 32, and
33 between the ridges 5, 6, 7, 8, and 9. The vacuum cup assembly
adheres tenaciously to the surface 13 but, because of the presence
of the lubricant on surface 13, between the ridges 5-9 and
underneath them, the vacuum cup assembly can slide on surface 13
relatively easily. Filter 3 is not essential to the operation of
the vacuum cup assembly but is preferred because the vacuum
continually draws stray particles from the surface and the air, as
well as some lubricant, into the vacuum system. Filter 3 will
minimize down time caused by fouling of the vacuum system. In a
different preferred configuration, we do not use a filter in the
vacuum cup assembly, but pass the vacuum air through a device for
removing lubricant from the air and recycling it; this may be done
either in individual units for each vacuum cup assembly or,
preferably, in a central area where the lubricant is collected.
[0021] While a lubricant source near the edge of vacuum cup 1 is
preferred, particularly after startup and the unit is proceeding
more or less in a single direction, it is not essential that the
lubricant contact the bottom surface of the vacuum cup 1 at an
outermost point. Port 10 may be located at a point nearer the
center of the vacuum cup 1, as the flow of lubricant is to be
coordinated with the application of vacuum and the variable
directional movement of the robot as a whole, so that a dry portion
of vacuum cup 1 will not unnecessarily be forced to move against
the work surface. More than one lubricant outlet such as port 10
may be used. The coordination of vacuum, lubricant flow, and power
and direction to the wheels (see the discussion with respect to
FIGS. 2a and 2b) may be accomplished more or less automatically by
appropriately written software or by manual input to the systems
which operate each. Any appropriate software and/or control system
capable of such coordination may be used. Preferably, the body of
vacuum cup 1 is generally conical and shallow, more or less as
depicted. As a major objective of our invention is to move the
robot while the vacuum cup assembly or assemblies provide adherence
to a work surface, it is important to understand the relationship
of certain variables relating to the suction cups. For example, the
sliding friction, F.sub.S, changes as a function of the reaction
force due to the suction cup, R.sub.SC. The reaction force R.sub.SC
is the tendency of the suction cup to release itself, primarily due
to its resilience, from the work surface, but it is also influenced
by the weight of the robot, the strength of the vacuum, and the
inner and outer areas of the suction cup. Generally the reaction
force conforms to the following relationship:
.SIGMA.F.sub.hor.=R.sub.SC+N+p.sub.v(A.sub.I)-p.sub.a(A.sub.o)=0
R.sub.SC=p.sub.a(A.sub.o)-N-p.sub.v(A.sub.I)
[0022] where R.sub.SC is the reaction force due to the suction cup
characteristics, p.sub.v is the vacuum pressure applied to the
suction cup, p.sub.a is the atmospheric pressure acting on the
outside of the suction cup, A.sub.o is the outside area of the
suction cup, A.sub.I is the inside area of the suction cup, and N
is the normal force acting or load applied to the suction cup,
usually the vehicle weight. The main variable available for control
of a single vacuum cup is the vacuum pressure applied, which
generally will be maintained sufficient to overcome the forces
tending to release the vacuum cup; however, this will not always be
the case where there is more than one vacuum cup assembly, and the
microprocessor should be programmed to manipulate the robot
accordingly. The sliding friction, F.sub.S varies with the number
of concentric ridges actually in contact with the working surface
under a given vacuum pressure, as well as the viscosity and
lubricity of the lubricant, the frictional characteristics of the
working surface and the composition (frictional characteristics) of
the vacuum cup body. Sliding function F.sub.S is used as a factor
in determining the motive power delivered to the wheels.
[0023] Referring now to FIG. 2a, robot body 14 is shown in its
preferred boomerang shape, viewed from the underside. On the body
14 are vacuum cup assemblies 15 and wheel assemblies 16. Utility
socket 17, located on the top surface of body 14, is shown as a
dotted line; utility socket 17 is for placement of various kinds of
tools, welders, spray tubes or nozzles, dispensers, and the like.
They may be in the form of extensible arms so their functions may
be performed on portions of the underlying surface somewhat remote
from the body 14. Body 14 may also have linking sites 18 for
linking the robot bodies together if desired. The boomerang shape
is preferred because it enables us to place wheels and vacuum cups
in trailing and spaced-apart relation to a lead module 19 of a
vacuum cup assembly 15 and wheels 16. Thus the basic configuration
of the lead module 19 and the (at least two) trailing modules 20
and 21 in our preferred configuration is more or less triangular.
Preferably the modules form the general shape of an equilateral
triangle--that is, the three modules 19, 20, and 21 are at the
apexes of a triangle, so that as the lead module 19 ascends an
inclined or backwardly leaning surface, steering is more
controllable than it would be if the rear of the robot were not in
contact with the work surface at spaced apart points. It will be
appreciated that this stabilizing effect will be facilitated when
the robot moves in any direction, and that the relative positions
of the working parts--the wheels and vacuum cup assemblies--are
significant. Any frame shape (boomerang, triangle, delta or other)
for the robot body which accomplishes the desired spacing and
achieves the desired stability will suffice. We intend to include
in our invention any device for articulation of the body (a body of
any shape), such as one or more hinges or motorized hinges which
may divide the body into parts. The flexing of the hinges may be
controlled remotely along with the other functions of the robot.
Modules 19, 20, and 21 may be turned independently in any
direction; wheels 16 may also be turned independently in any
direction.
[0024] As seen in FIG. 2b, the under side of body 14 is shown in a
preferred convex form, but may assume other shapes depending on the
kinds of surfaces on which the robot will be used. Vacuum cup
assembly 15a is seen to have articulating means 22 for application
to a surface which does not conform to the convex curve of body 14.
Wheel assemblies 16 (not shown in FIG. 2b) can be extended also so
the wheels 19 can reach and make contact on the surface.
[0025] In FIG. 3, our robot is seen to be in motion, carrying out a
painting task. The robot is on a hull surface 100, traveling
upwards. Two vacuum cup assemblies 101 are shown, fully
applied--that is, a full vacuum is drawn on them through vacuum
lines 102 which may lead to an optional manifold or chamber 103.
Vacuum pump 122 is shown to be mounted on the robot body, connected
to chamber 103, but chamber 103 may alternatively or in addition be
connected by an air line to a remote vacuum source not shown.
Lubricant is intermittently or continuously applied to the
advancing sides of vacuum cup assemblies 101 by pump 106 through
ducts 107 to form a film between the work surface and the vacuum
cup, the ultimate lubricant source being a reservoir not shown
connected to pump 106 through flexible tube 109. As lubricant is
fed through ducts 107, it spreads underneath the vacuum cup
assemblies 101, enabling the vacuum cup assemblies 101 to slide
freely on surface 100 when motive force is applied through wheels
110. Wheels 110 are urged outward by springs 111 so they will
contact surface 100 even if it is convex as the surface 100 may be.
The outward urging of the wheels is in conflict with the action of
the vacuum cups, but both are controlled appropriately by a
microprocessor not shown. Driving force is applied to wheels 110 by
motors 112. Motors 112 can apply variable turning force to wheels
110 and also can turn the wheels 110 to reorient the robot's
direction of movement. Each wheel may have its own controller, but
a single controller may be used for all wheels on the robot. The
controller may receive directions by flexible wire or by radio from
a remote microprocesor. As the purpose of the illustrated excursion
is to apply paint to a ship's hull (surface 100), a berth in the
form of utility socket 114 is equipped with a paint reservoir and
pump containing paint tube 116 leading to spray nozzle 117 for
spraying paint behind the robot as it moves. The orientation of
turret 115 can be controlled by a motor not shown in the utility
socket 114. The motor may in turn be controlled by its own
controller, not shown, or a central controller located on the robot
which may control all functions of the robot--that is, the
orientation and powering of wheels 110, variations in vacuum
strength to each of the vacuum assemblies, the flow of lubricant to
each of the vacuum assemblies, the vacuum source 104, and paint
pump 118, as well as the position of turret 115.
[0026] It should be noted that while vacuum cup assemblies 101
adhere to surface 100 with a significant tenaciousness as a
function of the applied vacuum, wheels 110 must apply traction to
move the robot forward, and accordingly the springloaded downward
force on wheels 101 is balanced so as not to overcome the vacuum
applied in the vacuum cup assemblies 101. This is made possible not
only by the programmed microprocessor, but by the use of our
lubricant, which permits excellent adhesion by vacuum while also
facilitating the sliding of the vacuum cup assemblies on the
lubricated surface 100.
[0027] Referring now to FIGS. 4a-4d, this series of figures is
designed to show how my robot can approach a backwardly inclined
surface such as a ship's hull and begin to ascend it to perform a
task. In FIG. 4a, the robot 14 is moved from right to left, as
depicted, by locomotion provided by wheels 40 contacting horizontal
surface or floor 41; the wheels 40 are controlled to direct the
robot in the leftward direction by an operator and microprocessor
not shown, through radio signals received by antenna 42 and/or
wires not shown. The signals are further processed on the robot by
a receiver not shown and utilized to manipulate the wheels 40--that
is to both steer and power them. At the point illustrated in FIG.
4a, module 44 containing wheels and a vacuum cup assembly on the
upper left of robot 14 has made contact with the ship's hull 43.
The microprocessor and/or one or more algorithms in a suitable form
detects the resistance caused by ship's hull 43 and begins rotating
the wheels in contact with ship's hull 43, at the same time also
activating the vacuum in the vacuum cup assembly including the step
of feeding lubricant to it. The module 44 is able to articulate or
tilt to accommodate the angle of ship's hull 43 or other surface.
While the wheels in module 44 tend to propel robot 14 upward and
backward, following the contour of ship's hull 43, wheels 40 will
cease to propel the robot 14 in a leftward direction, as this may
tend to jam the robot 14 into the acute angle formed by ship's hull
43 and horizontal surface 41. If the angle is significantly less
than that shown, wheels 40 on horizontal surface 41 must be free to
rotate in a backwards direction while robot 14 makes its initial
upward move on the ship's hull 43.
[0028] At the position of FIG. 4b, robot 14 has become adhered to
ship's hull 43 by at least two vacuum cup assemblies. The wheels on
horizontal surface 41 may be reactivated to assist in pushing robot
14 leftward, if they had been inactivated. The robot 14 becomes
oriented soon as shown in FIG. 4c, with vacuum cup assemblies and
wheel sets 46 and 47 in contact with ship's hull 43. The workings
of these sets of wheels and vacuum assemblies will tend to lift the
entire robot 14 from horizontal surface 41; however, wheel set 45
at the back corner of robot 14 should continue to push to the left
in order to assure orientation of robot 14 on ship's hull 43. This
means that module 46 of wheels and a vacuum cup assembly (the
uppermost set in contact with the ship's hull) should be released
and wheel set and vacuum assembly module 47 (the other ones in
contact with the ship's hull) should be directed to slide backwards
(that is, in a downward direction on the ship's hull) as the lower
end of the robot 14 proceeds leftward and orients robot 14 to an
orientation permitting adherence of a maximum number of vacuum cup
assemblies and wheel assemblies, as shown in FIG. 4d. This entire
procedure may be assisted by a sensor for detecting contact with
ship's hull 43. After the position of FIG. 4d is attained, the
robot will be ready for any of numerous tasks including ones
requiring carrying significant weights of equipment.
[0029] In FIGS. 5a and 5b, wheels 60 are seen to be driven by
motor/gear assembly 61, with a spring 62 between to urge the wheels
toward the surface 63. A module chassis 64 permits appropriate
orientation and alignment of vacuum cup 65, and the individual
vacuum pump and motor 66. FIG. 5b is a view from underneath. FIG. 6
illustrates the use of linkages 70, 71, 72, 73, 74, and 75, to
connect three robot bodies 77, 78, and 79 in a caravan or train so
that sequential tasks may be performed. As seen, robot body 77
distributes cleaning fluid through spray nozzle 80 onto the work
surface, the following robot body 78 employs a brush 81 to abrade
the work surface having been spread with cleaning fluid, and the
last robot body 79 sprays a rinse solution onto the work surface
through nozzle 82 after the brush 81 has assisted the cleaning
solution.
[0030] Referring now to FIG. 8, vacuum cup 1 is attached to stem 2
which carries vacuum line 102 through to the vacuum cup 1. Filter 3
is placed in the vacuum conduit as shown, but may be placed further
up in the stem assembly. Lower housing 201 and upper housing 203
hold compressed springs 202 and 204, which may work against each
other to provide flexibility and stability to the position of the
vacuum cup 1 to the robot body 14. Stem 2 is able to move
vertically through body 14. In vacuum line 102 are shown a vacuum
pump 122, check valve 200, and vacuum chamber 103. Additional
valves may be placed in vacuum line 102 between chamber 103 and
stem 2, or elsewhere. Filter 3 minimizes the fluid picked up in
vacuum line 102 and guards against solid particles being sucked up
into the mechanism. Vacuum chamber 103 prevents abrupt changes in
the strength of the vacuum reaching the vacuum cup 1, which could
lead to loss of adhesion to the surface. As indicated above, the
preferred construction has a plurality of vacuum cups 1, and as
each may be subject to different tensions, springs 202 and 204 are
useful to stabilize the unit and inhibit counterproductive forces
between vacuum assemblies. It will be understood that the level of
body 14 with respect to the working surface may be slightly
different from vacuum cup to vacuum cup.
[0031] We may use any suitable liquid lubricant which may be fed
through the vacuum cup as shown and illustrated, to spread on the
work surface, for the vacuum cups to contact. Fatty acids,
glycerols, triglycerols, graphite lubricant, vegetable and mineral
oil, and petroleum oils may be used. Preferably the lubricant will
be nonflammable and readily removed from the work surface by
water.
* * * * *