WO2006083094A1

WO2006083094A1 - Three-dimensionally movable absorption-type robot and moving method thereof

Info

Publication number: WO2006083094A1
Application number: PCT/KR2006/000323
Authority: WO
Inventors: Joon Mo Yang
Original assignee: Joon Mo Yang
Priority date: 2005-02-02
Filing date: 2006-01-27
Publication date: 2006-08-10

Abstract

The present invention relates to a surface-clinging type robot that has reduced weight and better mobility by employing the lowest number of adhering plates and that allows three-dimensional movement between a wall and a ceiling as well as typical two-dimensional movement. The robot has two adhering plates. The second adhering plate moves upward by a first up/down driving unit while the first adhering plate is in contact with a surface, and rotates on the first adhering plate by a first horizontal rotating unit. Then the second adhering plate moves downward by the first up/down driving unit, and clings to the surface by a clinging force supplied thereto.

Description

[DESCRIPTION]

[Invention Title]

THREE-DIMENSIONALLY MOVABLE ADSORPTION-TYPE ROBOT

AND MOVING METHOD THEREOF

[Technical Field]

The present invention relates generally to a robot and, more particularly,

to a surface-clinging type robot that adheres to a wall or a ceiling by a clinging

force and that is capable of three-dimensionally moving.

[Background Art]

When there is a need for cleaning the exterior or the interior of a building,

a working person directly executes such cleaning as he hangs by a rope in

midair.

However, as high-rise or multi-storied buildings increase recently, such

cleaning by a person becomes more dangerous since a much longer rope is

required. Especially, if the exterior wall of the building is formed of a smooth

plane such as glass, it may be difficult to even approach the exterior wall for

cleaning.

To solve these problems, robots that can move on the wall or the ceiling

have been developed. Most conventional robots have adhering plates in which a clinging force is created by an vacuum assembly or a magnetic wheel

assembly. So such robots cling to the wall or the ceiling through the adhering

plates and then move thereon.

Therefore a clinging force in the adhering plates is very essential to

clinging-type robots. Conventional robots have, however, an insufficient clinging

force to cling to or move on the wall or the ceiling. So such robots employ

several adhering plates or auxiliary units to enhance a clinging force.

Unfortunately, many adhering plates or auxiliary units may complicate

the structure of the robot, causing the difficulty of control and the increase of

weight.

Moreover, conventional robots move in general two-dimensionally only

and fail to move three-dimensionally, for example, from the wall to the ceiling.

[Disclosure]

[Technical Problem]

One object of the present invention is to provide a surface-clinging type

movable robot with reduced weight and better mobility by employing the lowest

number of adhering plates. Another object of the present invention is to provide a surface-clinging

type movable robot allowing three-dimensional movement as well as typical

two-dimensional movement.

[Technical Solution]

In one exemplary embodiment of the invention, a three-dimensionally

movable robot comprises two moving units, supporting units, connecting units, a

vertical rotating unit, up/down driving units, and horizontal rotating units.

Each moving unit has an adhering plate and a leg joined to the adhering

plate. The moving units allow surface-clinging movement on a surface by

supplying a clinging force to a clinging space between the adhering plate and

the surface. The supporting units respectively support the moving units. The

connecting units are spaced apart from each other. Each connecting unit is

joined to the supporting unit at a first end. The vertical rotating unit is disposed

between the connecting units and links second ends of the connecting units.

The vertical rotating unit urges the moving unit to rotate vertically on the surface.

The up/down driving units are respectively fixed to the supporting units and

drive the supporting units upward/downward such that the moving unit moves in

a vertical direction on the surface. The horizontal rotating units are respectively fixed to the supporting units and urges the moving units to rotate horizontally on

the surface.

In the robot of the present invention, each moving unit may have an

vacuum assembly that supplies a clinging force to the adhering plate. The

vacuum assembly may be disposed apart from the adhering plate.

In the robot of the invention, while one moving unit clings to the surface,

the vertical rotating unit may laterally expand or shrink toward the other moving

unit.

In the robot, the up/down driving unit may have a screw nut fixed to the

supporting unit, a rotating extendable shaft inserted in the screw nut, and an

up/down driving gear motor fixed between the connecting units to rotate the

shaft.

In the robot, the horizontal rotating unit may have a worm gear partly

surrounding the moving unit, a pinion vertically engaged with the worm gear,

and a rotating driving gear motor offering a rotating force to the pinion.

In the robot, the vacuum assembly may have a cylinder joined to the

moving unit, a piston located in the cylinder, a piston gear motor driving

upward/downward the piston, a piston driving arm connecting the piston and the

piston gear motor, and a coupling tube joined to the cylinder and the adhering plate, wherein the clinging space of the adhering plate communicates with the

inside of the cylinder through the coupling tube.

In the robot, the adhering plate may be a rigid, thin, circular plate.

In the robot, the adhering plate may have a pressure sensor that

measures a clinging force generated in the clinging space, and an inflow valve

that allows a rapid inflow of the air into the clinging space of the adhering plate.

In the robot, the leg may change in length such that the moving unit can

go over an obstacle existing on the surface.

In another exemplary embodiment of the invention, a moving method of

three-dimensionally movable surface-clinging type robot having first and second

adhering plates is provided. The method comprises moving upward the second

adhering plate by operating a first up/down driving unit while the first adhering

plate is in contact with a surface, rotating the second adhering plate on the first

adhering plate by using a first horizontal rotating unit, moving downward the

second adhering plate by operating the first up/down driving unit, supplying a

clinging force to the second adhering plate so as to cling to the surface, and

removing a clinging force from the first adhering plate. The method further

comprises moving upward the first adhering plate by operating a second

up/down driving unit, rotating the first adhering plate on the second adhering

plate by using a second horizontal rotating unit, moving downward the first adhering plate by operating the second up/down driving unit, and supplying a

clinging force to the first adhering plate so as to cling to the surface.

[Effects]

Since an adhering plate has the smallest clinging space that creates a

relatively higher clinging force, a robot of the present invention can employ only

two adhering plates for surface-clinging movement. So the robot of the invention

may have a simpler structure, relative ease of control, reduced weight, better

mobility, and lower production cost.

Additionally, a robot of the invention can move along an extension line

that links both moving units by means of an extendable, vertical rotating unit.

Such actions of the robot allow a reliable movement in a relatively narrow space

disallowing rotation.

Moreover, a robot of the invention can move three-dimensionally

between the wall and the ceiling by using a vertical rotating unit as well as a

horizontal rotating unit.

[Description of Drawings]

FIG. 1 is a perspective view showing a three-dimensionally movable

surface-clinging type robot in accordance with the present invention. FIG. 2 is a cross-sectional view showing a moving unit of the robot

shown in FIG. 1.

FIG. 3 is a side view showing a horizontal rotating unit of the robot

shown in FIG. 1.

FIG. 4 is a schematic view to explain the clinging force of the robot

shown in FIG. 1.

FIG. 5 is a side view showing a state in which the robot shown in FIG. 1

adheres to a wall.

FIG. 6 is a side view showing a state in which a second moving unit of

the robot shown in FIG. 5 ascends.

FIG. 7 is a side view showing a state in which a vertical rotating unit of

the robot shown in FIG. 6 expands in length.

FIG. 8 is a plan view showing two-dimensional movement of the robot

shown in FIG. 5 on the wall.

FIG. 9 is a side view showing three-dimensional movement of the robot

shown in FIG. 5 from the wall to the ceiling.

[Best Mode]

FIG. 1 is a perspective view showing a three-dimensionally movable

surface-clinging type robot in accordance with the present invention. FIG. 2 is a cross-sectional view showing a moving unit of the robot shown in FIG. 1. FIG. 3

is a side view showing a horizontal rotating unit of the robot shown in FIG. 1.

Referring to FIGS. 1 to 3, the robot 100 includes two moving units 101 ,

supporting units 102, connecting units 103, vertical rotating units 104, up/down

driving units 105, and horizontal rotating units 106. The robot 100 has a

symmetric structure about the vertical rotating units 104. The moving unit 101

moves on a surface such as a wall or a ceiling by using a clinging force, The

supporting unit 102 supports the moving unit 101. The connecting unit 103

connects the supporting unit 102 and the vertical rotating unit 104. The vertical

rotating unit 104 couples the connecting units 103 and provides vertical rotation

on the surface. The up/down driving unit 105 urges the moving unit 101

upward/downward. The horizontal rotating unit 106 rotates the moving unit 101

horizontally on the surface.

The moving unit 101 has a rod-like leg 111 , an adhering plate 112 joined

to the lowermost of the leg 111 , and an vacuum assembly 107 joined to the

uppermost of the leg 111. The vacuum assembly 107 supplies a clinging force

to the adhering plate 112 allowing surface-clinging movement. The leg 111 may

change in length, so the moving unit 101 can go over an obstacle occasionally

existing on the surface. The vacuum assembly 107 has a cylinder 114, a piston 115, a piston

gear motor 116, a piston driving arm 128, and a coupling tube 117. The cylinder

114 is joined to the uppermost of the moving unit 101. The piston 115 is located

in the cylinder 1 14 so as to change inside pressure of the cylinder 114. The

piston gear motor 116 drives upward and downward the piston 115. The piston

driving arm 128 connects the piston 115 and the piston gear motor 116. The

coupling tube 117 is joined to a lower part of the cylinder 1 14 at one end and to

the adhering plate 112 at the other end, passing both the leg 111 and an axis of

a worm gear 121. So, a clinging space of the adhering plate 112 communicates

with the inside of the cylinder 114 through the coupling tube 117.

The vacuum assembly 107 is disposed apart from the adhering plate

112, but is connected through the coupling tube 117. If the vacuum assembly

107 is directly attached to the adhering plate 112, there is a possibility that lines

for supplying electric power to the vacuum assembly 107 or the piston gear

motor 116 will obstruct horizontal movement. A typical small vacuum pump may

be alternatively used for the vacuum assembly 107.

The adhering plate 112 is a rigid, thin, circular plate. The center of the

adhering plate 112 is fastened to the leg 111 of the moving unit 101 by a

connector 112a. A contact ring 112b with a predetermined thickness is attached

to peripheral edges of a lower face of the adhering plate 1 12. The contact ring 112b will be in contact with the surface such as a wall or a ceiling, and block the

flow of air between the clinging space (1 13 of FIG. 4) and the outside.

When the adhering plate 112 is in contact with the surface and then the

piston 115 moves upward by the piston gear motor 116, the air existing in the

internal space between the adhering plate 112 and the surface flows into the

cylinder 114 through the coupling tube 1 17. So, a pressure of the clinging space

is reduced and thereby a clinging force is created. Contrary to that, when the

piston 115 moves downward, the air in the cylinder 114 flows into the internal

space, diminishing a clinging force.

When the adhering plate 112 is in contact with the surface and then the

horizontal rotating unit 106 operates, the moving unit 101 including the cylinder

114, the piston 115, the coupling tube 117, the worm gear 121 and the leg 111

remains a stationary state. The other members except the moving unit 101

rotate around the worm gear 121. The piston gear motor 1 16 drives the piston

1 15 upward and then rotates during horizontal rotation. At this time, the piston

driving arm 128 not only maintains a rising state of the piston 115, but also acts

as the borderline between rotating members and clinging members on the

surface.

The adhering plate 112 may further has a pressure sensor 126 for

detecting the abnormality of a clinging force generated in the internal space. The preliminary detection of a pressure in the internal space by the pressure

sensor 126 may prevent the robot 100 from falling from the surface due to an

abnormal clinging force.

When the air flows in the internal space of the adhering plate 112 by

descending the piston 115, the adhering plate 112 may fail to be detached due

to insufficient flow of the air. To prevent this, an inflow valve 127 may be

additionally formed on the adhering plate 112. During detaching the adhering

plate 112, the inflow valve 127 may allow a rapid inflow of the air into the

internal space of the adhering plate 112. The pressure sensor 126 and the

inflow valve 127 may be located on the adhering plate 112 as shown in FIG. 1 ,

but may be positioned around the cylinder 114.

Hereinafter, a clinging force that is generated in the internal space of the

adhering plate 112 will be described with reference to FIG. 4. FIG. 4 is a

schematic view to explain the clinging force of the robot shown in FIG. 1.

The magnitude of a clinging force in the clinging space 113 is calculated

by the product between the area (S) of the clinging space 113 and the

difference between a pressure of an internal space of the moving unit 101 and

an external pressure. Here, the internal space may include the inside of the

cylinder 114, the inside of the coupling tube 117, and the clinging space 113

between the adhering plate 112 and the surface 124. Let's suppose that the volume of the internal space is ¹A' when the

piston 115 is located at the first position (a) in the cylinder 114. At this time, the

pressure of the internal space is equal to the atmospheric pressure of external

surroundings. When the piston 115 moves to the second position (b), the

volume of the internal space increases by 'B' and thus sums to 'A+B'. Here, the

difference in pressure between the internal space and the external surroundings

is '1 -A/(A+B)\ that is, 'B/(A+B)' (kgf/cm², atm). Therefore, as the volume ¹A¹ is

smaller or the volume ¹B¹ is greater, a pressure difference becomes greater. If

the area of the clinging space 113 is 'S', the clinging force becomes 'BS/(A+B)'

(kgf). For example, in case where S=200cm² and A=B, that is, the volume of the

clinging space 113 increases twice, the clinging force is as much as I OOkgf

corresponding to 100 kilograms in weight of human.

As discussed above, the robot 100 of the invention may use a strong

clinging force generated in the adhering plate 112. Therefore, even though only

one of the moving units 101 clings to the surface, the leg 111 joined to the

adhering plate 112 can hardly shake. Additionally, even though the center of

gravity moves downward, the robot 100 does not easily lean downward, nor is

separated from the surface. The clinging space 113 with smaller volume but

greater area may produce a stronger clinging force without requiring several

adhering plates 112. Returning to FIGS. 1 to 3, the supporting unit 102 mechanically supports

the moving unit 101. The connecting unit 103 is connected to the supporting

unit 102 at one end and to the vertical rotating unit 104 at the other end. Two

groups of the connecting units 103 are disposed near both ends of the vertical

rotating unit 104 and coupled through the vertical rotating unit 104. So, the

supporting units 102 are spaced apart from each other.

The vertical rotating unit 104 links the connecting units 103. While one

of the moving units 101 clings to the surface, the vertical rotating unit 104

rotates in a vertical direction on the surface the other moving unit 101 and the

supporting unit 102 joined thereto. The vertical rotating unit 104 may expand or

shrink laterally as shown in FIG. 7. In addition, the vertical rotating unit 104 or

the connecting unit 103 may be equipped with a cleaning tool that removes

foreign matters from the surface and/or a video camera that captures image and

sound. The cleaning tool may include a gripper, a duster, a vacuum suction,

and a nozzle for directing a cleaning solution, water, or a compressed air.

The up/down driving unit 105 has a screw nut 118 fixed to the

supporting unit 102, a rotating extendable shaft 119 inserted in the screw nut

118, and an up/down driving gear motor 120 fixed between the connecting units

103 and rotating the shaft 119. When the shaft 119 is rotated in a state where

one of the moving units 101 clings to the surface, a length between the shaft 119 and the screw nut 118 is changed. The connecting unit 103 is therefore

rotated and thus drives the moving unit 101 upward/downward.

The horizontal rotating unit 106 has a worm gear 121 partly surrounding

the moving unit 101 , a pinion 122 vertically engaged with the worm gear 121 ,

and a rotating driving gear motor 123 offering a rotating force to the pinion 122.

When the pinion 122 is rotated by the rotating driving gear motor 123 in a state

where one of the moving units 101 clings to the surface, the other members

except the clinging moving unit 101 are rotated horizontally on the surface.

As discussed, the robot 100 of the invention can three-dimensionally

move by means of the vertical rotating units 104. This is one of distinctive

features of the robot of the invention in comparison with conventional robots.

FIG. 5 is a side view showing a state in which the robot shown in FIG. 1

adheres to a wall, and FIG. 6 is a side view showing a state in which a second

moving unit of the robot shown in FIG. 5 ascends. Furthermore, FIG. 7 is a side

view showing a state in which a vertical rotating unit of the robot shown in FIG.

6 expands in length, and FIG. 8 is a plan view showing two-dimensional

movement of the robot shown in FIG. 5 on the wall.

In FIGS. 5 to 8, to assist a better understanding of actions of the moving

units 101 , one of the moving units 101 will be referred to as a first moving unit

101 a, whereas the other will be referred to as a second moving unit 101 b. Referring to FIG. 5, a clinging force occurs in the clinging space

between the adhering plate 112 and the wall surface 124 by each vacuum

assembly of the first and second moving units 101 a and 101 b. So, both the

moving units 101a and 101 b are in contact with and clinging to the wall surface

b r 124.

First, referring to FIG. 6, in a first step, a clinging force is removed from

the adhering plate 112 of the second moving unit 101 b. Then, in a second step,

by operating the up/down driving unit 105 of the first moving unit 101a, the

second moving unit 101b moves upward.

0 Next, in a third step, the horizontal rotating unit 106 of the first moving

unit 101a operates to horizontally rotate the other members except the first

moving unit 101a (© in FIG. 8). Then, in a fourth step, the second moving unit

101 b moves downward by the up/down driving unit 105 of the first moving unit

101a.

5 Next, in a fifth step, a clinging force occurs in the clinging space

between the adhering plate 112 of the second moving unit 101 b and the wall

surface 124. Thereafter, the first to fifth steps are repeated to the first moving

unit 101a, so the first moving unit 101a horizontally rotates as shown d) in FIG.

8. In case where the legs of the moving units 101 change in length, a step

of expanding the legs may be added between the second and third steps, and a

step of shrinking the legs may be added between the fourth and fifth steps.

Additionally, as shown in FIG. 7, in case where the vertical rotating unit

104 changes in length, a step of expanding to the second moving unit 101 b or

shrinking to the first moving unit 101a may be added between the second and

third steps.

Accordingly, the robot 100 of the invention can freely moves on a two-

dimensional wall surface 124 as shown in FIG. 8.

As shown in FIG. 7, the vertical rotating unit 104 can be expanded or

shrunk in length. So, the robot 100 can move on the wall surface 124 without

rotating. In this case, the first and second moving units 101a and 101 b move

along an extension line that links both the moving units 101a and 101 b.

Referring to FIG. 7, while both the moving units 101a and 101 b are in

contact with and clinging to the wall surface 124, a clinging force is removed

from the second moving unit 101 b in a first step. Then, the second moving unit

101 b moves upward in a second step.

Next, the vertical rotating unit 104 is expanded in length to the second

moving unit 101 b in a third step. Then, the second moving unit 101 b moves

downward in a fourth step. Next, a clinging force occurs in the clinging space between the second

moving unit 101 b and the wall surface 124 in a fifth step, and a clinging force

within the first moving unit 101 a is removed in a sixth step.

Next, the vertical rotating unit 104 is shrunk to the second moving unit

101 b in a seventh step. So, the first moving unit 101 a moves toward the second

moving unit 101b clinging to the wall surface 124.

Next, the first moving unit 101a moves downward in an eighth step, and

a clinging force occurs again in the clinging space between the first moving unit

101 a and the wall surface 124 in a ninth step.

While the first to ninth steps are repeated to both the moving units 101a

and 101 b, the robot 100 of the invention can move along an extension line that

links both the moving units 101a and 101 b. Moreover, such actions of the robot

100 can allow movement in a relatively narrow space disallowing rotation.

FIG. 9 is a side view showing three-dimensional movement of the robot

shown in FIG. 5 from the wall to the ceiling.

Referring to FIG. 9, a clinging force occurs in the clinging space

between the adhering plate 112 and the wall surface 124 by each vacuum

assembly of the first and second moving units 101a and 101 b. So, both the

124. In a first step, a clinging force is removed from the adhering plate 112 of

the second moving unit 101b. Then, as shown in FIG. 6, the second moving unit

101 b moves upward by the up/down driving unit 105 of the first moving unit

101a in a second step.

Next, in a third step, the second moving unit 101b rotates to 90 degrees

in a horizontal direction on the wall surface 124 by the horizontal rotating unit.

Then, in a fourth step, the second moving unit 101 b rotates to 90 degrees in a

vertical direction on the wall surface 124 by the vertical rotating unit.

Next, in a fifth step, the second moving unit 101 b moves downward to

be contact with the ceiling surface 125. Then, in a sixth step, a clinging force

occurs in the clinging space between the second moving unit 101 b and the

ceiling surface 125 by the vacuum assembly.

Next, in a seventh step, a clinging force is removed from the first moving

unit 101a, and, in an eighth step, the first moving unit 101a rotates to 90

degrees on the wall surface 124 by the vertical rotating unit 104. Here, the first

moving unit 101a may move upward by the up/down driving unit 105 between

the seventh and the eighth steps.

Such three-dimensional movement of the robot 100 may be performed

from the wall surface 124 to the ceiling surface 125, and vice versa. [Industrial Applicability]

A three-dimensionally movable, surface-clinging type robot of the

present invention may be applicable to a variety of fields including, but not

limited to, cleaning robots, monitoring or reconnaissance robots, attention-

getting robots on show window, movable toy robots, etc.

Claims

[CLAIMS]

[Claim 1 ]

A three-dimensionally movable robot comprising:

two moving units each having an adhering plate and a leg joined to the

adhering plate, the moving units allowing surface-clinging movement on a

surface by supplying a clinging force to a clinging space between the adhering

plate and the surface;

supporting units respectively supporting the moving units;

connecting units spaced apart from each other, each connecting unit

joined to the supporting unit at a first end;

a vertical rotating unit disposed between the connecting units and linking

second ends of the connecting units, the vertical rotating unit urging the moving

unit to rotate vertically on the surface;

up/down driving units respectively fixed to the supporting units and

driving the supporting units upward/downward such that the moving unit moves

in a vertical direction on the surface; and

horizontal rotating units respectively fixed to the supporting units and

urging the moving units to rotate horizontally on the surface.

[Claim 2] The robot of claim 1 , wherein each moving unit has an vacuum

assembly that supplies a clinging force to the adhering plate.

[Claim 3]

The robot of claim 2, wherein the vacuum assembly is disposed apart

from the adhering plate.

[Claim 4]

The robot of claim 1 , wherein while one moving unit clings to the surface,

the vertical rotating unit laterally expands or shrinks toward the other moving

unit.

[Claim 5]

The robot of claim 1 , wherein the up/down driving unit has a screw nut

fixed to the supporting unit, a rotating extendable shaft inserted in the screw nut,

and an up/down driving gear motor fixed between the connecting units to rotate

the shaft.

[Claim 6] The robot of claim 1 , wherein the horizontal rotating unit has a worm

gear partly surrounding the moving unit, a pinion vertically engaged with the

worm gear, and a rotating driving gear motor offering a rotating force to the

pinion.

[Claim 7]

The robot of claim 2, wherein the vacuum assembly has a cylinder

joined to the moving unit, a piston located in the cylinder, a piston gear motor

driving upward/downward the piston, a piston driving arm connecting the piston

and the piston gear motor, and a coupling tube joined to the cylinder and the

adhering plate, wherein the clinging space of the adhering plate communicates

with the inside of the cylinder through the coupling tube.

[Claim 8]

The robot of claim 1 , wherein the adhering plate is a rigid, thin, circular

plate.

[Claim 9]

The robot of claim 1 , wherein the adhering plate has a pressure sensor

that measures a clinging force generated in the clinging space.

[Claim 10]

The robot of claim 1 , wherein the adhering plate has an inflow valve that

allows a rapid inflow of the air into the clinging space of the adhering plate.

[Claim 11 ]

The robot of claim 1 , wherein the leg changes in length such that the

moving unit can go over an obstacle existing on the surface.

[Claim 12]

A moving method of three-dimensionally movable surface-clinging type

robot having first and second adhering plates, the method comprising:

moving upward the second adhering plate by operating a first up/down

driving unit while the first adhering plate is in contact with a surface, rotating the

second adhering plate on the first adhering plate by using a first horizontal

rotating unit, moving downward the second adhering plate by operating the first

up/down driving unit, supplying a clinging force to the second adhering plate so

as to cling to the surface, removing a clinging force from the first adhering plate,

moving upward the first adhering plate by operating a second up/down driving

unit, rotating the first adhering plate on the second adhering plate by using a second horizontal rotating unit, moving downward the first adhering plate by

operating the second up/down driving unit, and supplying a clinging force to the

first adhering plate so as to cling to the surface.