Mobile robot, robot movement system, and control method for mobile robot

Abstract

The mobile robot according to one embodiment includes a body, a plurality of units, and a member. Each of the plurality of units includes: a traveling device configured to travel on a surface in contact therewith; and a supporter supporting the traveling device and being movable with respect to the body to change the distance between the body and the traveling device. The plurality of units is disposed around the body. The member is provided with an internal space, is located between the body and the supporter, and is configured to expand when the internal space is filled with gas.

Description

Mobile robot, robot movement system, and control method for mobile robot

[0001] Embodiments of the present invention relate to a mobile robot, a robot movement system, and a control method for a mobile robot.

[0002] For example, a mobile robot for moving in a narrow space such as inside a pipe or a gap has a plurality of traveling devices such as movable wheels or crawlers. The mobile robot can maintain its posture and move by, for example, pressing each of the plurality of traveling devices against the inner surface of the pipe or both side surfaces of the gap. The mobile robot biases the traveling device by the elastic force of an elastic body, or displaces the traveling device by an air cylinder or various actuators.

[0003] Japanese Patent Laid-Open No. 5-170098

[0004] The elastic body biases the traveling device in one direction. Therefore, for example, when the traveling device sinks into a depression, it is difficult for the traveling device to escape from the depression. On the other hand, although the actuator can cause the traveling device to escape from the depression, it makes the mobile robot heavy.

[0005] An example of the problem to be solved by the present invention is to provide a mobile robot, a robot movement system, and a control method for a mobile robot that can be lightweight.

[0006] A mobile robot according to one embodiment includes a body, a plurality of units, and a member. Each of the plurality of units has a traveling device configured to travel on an abutting surface, and a support member that supports the traveling device and is movable relative to the body so that the distance between the body and the traveling device changes, and is arranged around the body. The member has an internal space, is located between the body and the support member, and is configured to expand by filling the internal space with gas.

[0007] Figure 1 is a schematic diagram showing the robot mobility system of the first embodiment. Figure 2 is a schematic side view showing a partially cut-out mobile robot of the first embodiment. Figure 3 is a cross-sectional view showing a part of the mobile robot with the arm unit deployed of the first embodiment. Figure 4 is a cross-sectional view showing the mobile robot of the first embodiment along the line F4-F4 in Figure 3. Figure 5 is a schematic diagram showing the movement of the mobile robot at a T-junction of the first embodiment. Figure 6 is a schematic diagram showing the mobile robot entering a gate valve of the first embodiment. Figure 7 is a schematic diagram showing the mobile robot exiting a gate valve of the first embodiment. Figure 8 is a schematic cross-sectional view showing the mobile robot according to the second embodiment. Figure 9 is a schematic side view showing the mobile robot according to the third embodiment. Figure 10 is a schematic side view showing the mobile robot according to the fourth embodiment. Figure 11 is a cross-sectional view showing a part of the mobile robot with the arm unit deployed of the fifth embodiment. Figure 12 is a schematic diagram showing the robot mobility system according to the sixth embodiment.

[0008] (First Embodiment) The first embodiment will be described below with reference to Figures 1 to 7. In this specification, the components of the embodiment and their descriptions may be described using multiple expressions. The components and their descriptions are examples and are not limited by the expressions used herein. The components may also be identified by names different from those used herein. Furthermore, the components may also be described using expressions different from those used herein.

[0009] In the following explanation, “suppress” is defined, for example, to prevent the occurrence of an event, action, or effect, or to reduce the degree of an event, action, or effect. Also, in the following explanation, “restrict” is defined, for example, to prevent movement or rotation, or to permit movement or rotation within a predetermined range while preventing movement or rotation beyond that predetermined range.

[0010] Figure 1 is a schematic diagram showing a robot mobile system 10 according to a first embodiment. The robot mobile system 10 includes a mobile robot 11, a cable 12, a pressurizing device 13, a plurality of regulators 14, a plurality of control valves 15, a pressure reducing device 16, a control device 17, a display device 18, and an input device 19. Figure 1 schematically shows the regulators 14 and control valves 15 individually. The robot mobile system 10 may have other devices and components. The pressurizing device 13 may also be called a pressure source. The pressure reducing device 16 may also be called a negative pressure source.

[0011] Figure 2 is a schematic side view showing a partially cut-out mobile robot 11 of the first embodiment. As shown in Figure 2, the mobile robot 11 has a body (main body) 21, a plurality of arm units 22, two inflatable structures 23, four restraint plates 24, two bands 25, a camera 26, and a sensor 27. The arm unit 22 is an example of a unit. The inflatable structure 23 is an example of a component and may also be called a balloon. The restraint plate 24 is an example of a wall.

[0012] The body 21 is formed in a substantially cylindrical shape, for example, from metal. However, the body 21 may be made of other materials or formed in other shapes. For example, the body 21 may be formed in a box shape.

[0013] In this specification, for convenience, the axial, radial, and circumferential directions of the central axis Axb of the body 21 are defined. The axial direction is the direction along the central axis Axb of the body 21. The axial direction includes the forward direction Dxf and the backward direction Dxb. The forward direction Dxf is an example of the direction of travel. The mobile robot 11 may also move in the backward direction Dxb. The radial direction is the direction perpendicular to the central axis Axb. The circumferential direction is the direction around the central axis Axb.

[0014] The body 21 has a front end surface 21a, a rear end surface 21b, an inner surface 21c, and an outer surface 21d. The front end surface 21a is located at the end of the body 21 in the forward direction Dxf and faces in the forward direction Dxf. The rear end surface 21b is located at the end of the body 21 in the rear direction Dxb and faces in the rear direction Dxb. The inner surface 21c and the outer surface 21d are substantially cylindrical curved surfaces that extend in the axial direction. The inner surface 21c faces inward in the radial direction; that is, the inner surface 21c faces the central axis Axb. The outer surface 21d is located on the opposite side of the inner surface 21c and faces outward in the radial direction.

[0015] An insertion hole 29 is provided on the inside of the body 21. The insertion hole 29 is defined by the inner surface 21c and opens to the front end surface 21a and the rear end surface 21b. The insertion hole 29 may be closed.

[0016] The multiple arm units 22 are formed to be substantially the same shape as each other. However, the shapes of the multiple arm units 22 may differ from each other. In this embodiment, the multiple arm units 22 include four front units 22F and four rear units 22B. The front units 22F are four of the multiple arm units 22. The rear units 22B are the other four of the multiple arm units 22. However, the number of front units 22F and rear units 22B is not limited to this example.

[0017] The four front units 22F are arranged at equal intervals in the circumferential direction. The four front units 22F are spaced apart from the four rear units 22B in the forward direction Dxf. The four rear units 22B are arranged at equal intervals in the circumferential direction. In other words, the multiple arm units 22 are arranged around the body 21. Each of the four front units 22F and the four rear units 22B has a deployment mechanism 31, a movement mechanism 32, a biasing member 33, an intermediate hinge 34, and a supporter 35.

[0018] The deployment mechanism 31 includes an end hinge 41 and an arm 42. The arm 42 is an example of a support member. The end hinge 41 is provided on the outer surface 21d of the body 21. The end hinge 41 holds the arm 42 so that it can rotate around a central axis Axa. The central axis Axa is an example of a first axis of rotation. The central axis Axa extends, for example, in the tangential direction of a virtual circle around the central axis Axb of the body 21.

[0019] Figure 3 is a cross-sectional view showing a part of the mobile robot 11 with the arm unit 22 of the first embodiment deployed. As shown in Figure 3, the arm 42 is formed in the shape of a rod extending from, for example, the end hinge 41. The arm 42 has a first mounting portion 42a and a second mounting portion 42b.

[0020] The first mounting portion 42a is provided at one end of the arm 42. The first mounting portion 42a is attached to the end hinge 41. That is, the first mounting portion 42a is attached to the body 21 via the end hinge 41 so as to be rotatable around the central axis Axa. The second mounting portion 42b is provided at the other end of the arm 42. That is, the second mounting portion 42b is spaced apart from the first mounting portion 42a.

[0021] As shown in Figure 2, the moving mechanism 32 has a traveling device 44 and a drive device 45. The traveling device 44 has two wheels 46. The traveling device 44 may also have other devices such as crawlers. The wheels 46 are mounted on the second mounting portion 42b so as to be rotatable about a central axis parallel to the central axis Axa. That is, the arm 42 supports the traveling device 44. The drive device 45 has a motor 47, such as a DC motor. The drive device 45 may also have a reduction gear. The motor 47 rotates the wheels 46, for example, through the reduction gear.

[0022] As shown in Figure 3, the arm 42 can rotate in an opening direction Dau and a closing direction Daf around the central axis Axa. The opening direction Dau is one direction around the central axis Axa. By rotating the arm 42 in the opening direction Dau, the travel device 44 moves away from the body 21. The closing direction Daf is the opposite direction to the opening direction Dau. By rotating the arm 42 in the closing direction Daf, the travel device 44 moves closer to the body 21. That is, the arm 42 is movable relative to the body 21 so that the distance between the body 21 and the travel device 44 changes. When the arm 42 is rotated to its maximum extent in the closing direction Daf, the arm 42 extends from the end hinge 41 in the rearward direction Dxb. Note that the direction in which the arm 42 extends is not limited to this example.

[0023] The deployment mechanism 31 may have other devices, such as a pantograph, instead of the end hinge 41 and arm 42. That is, the deployment mechanism 31 may move in parallel with the body 21, or move in any other way with respect to the body 21.

[0024] The biasing member 33 has a torsion coil spring 51. One end of the torsion coil spring 51 is supported directly or indirectly by the body 21. For example, one end of the torsion coil spring 51 is supported by the end hinge 41, and thus supported by the body 21 via the end hinge 41. The other end of the torsion coil spring 51 is supported by the first mounting portion 42a. The torsion coil spring 51 biases the arm 42 in the closing direction Daf relative to the body 21 by elastic force.

[0025] The intermediate hinge 34 is provided on the arm 42 between the first mounting portion 42a and the second mounting portion 42b. The intermediate hinge 34 is located between the body 21 and the arm 42.

[0026] The supporter 35 is formed in the shape of a plate, for example, positioned along the outer surface 21d of the body 21. The supporter 35 extends in the tangential direction of a virtual circle about the central axis Axb of the body 21. The end of the supporter 35 in the circumferential direction is bent in the tangential direction of a virtual circle about the central axis Axb of the body 21. The supporter 35 is not limited to this example and may extend in an arc shape in the circumferential direction, for example. The supporter 35 is attached to the intermediate hinge 34. That is, the supporter 35 is attached to the arm 42 via the intermediate hinge 34.

[0027] The supporter 35 is rotatable around the central axis Axs relative to the arm 42. The central axis Axs is an example of a second axis of rotation. The central axis Axs extends, for example, in the tangential direction of a virtual circle around the central axis Axb of the body 21. The central axis Axs is parallel to the central axis Axa.

[0028] The supporter 35 has a front edge 35a, an inner surface 35b, and an outer surface 35c. The front edge 35a is the end of the supporter 35 in the forward direction Dxf. The inner surface 35b faces inward in the radial direction. The outer surface 35c is located on the opposite side of the inner surface 35b and faces outward in the radial direction.

[0029] A notch 55 is provided in the supporter 35. The notch 55 opens on the front edge 35a, the inner surface 35b, and the outer surface 35c. In the circumferential direction, the width of the notch 55 is greater than the width of the arm 42.

[0030] Each of the two inflatable structures 23 is formed in the shape of a bag, for example, from a membrane or cloth. Therefore, each of the two inflatable structures 23 is provided with an internal space 60. The inflatable structure 23 can be any structure that has an enclosed internal space 60, expands when the internal space 60 is pressurized, and contracts when the internal space 60 is depressurized.

[0031] Figure 4 is a cross-sectional view of the mobile robot 11 of the first embodiment, along the line F4-F4 in Figure 3. As shown in Figure 4, the two inflatable structures 23 in the first embodiment are each formed in an annular shape extending in the circumferential direction. The two inflatable structures 23 each surround the body 21. In other words, the body 21 extends through the inside of the annular inflatable structures 23.

[0032] The inflatable structure 23 is attached to the body 21 by, for example, adhesive, fastening, or various other methods. This restricts the inflatable structure 23 from rotating around the central axis Axb relative to the body 21. For adhesive, for example, an adhesive or hook-and-loop fastener may be used. For fastening, for example, holes and wires passing through the holes may be used. The inflatable structure 23 may also be rotatable around the central axis Axb relative to the body 21. The inflatable structure 23 may also be attached to the supporter 35.

[0033] As shown in Figure 2, one inflatable structure 23 is located between the outer surface 21d of the body 21 and the arm 42 of the front unit 22F. The other inflatable structure 23 is located between the outer surface of the body 21 and the arm 42 of the rear unit 22B. Therefore, the outer surface 21d of the body 21 faces the arm unit 22 and the inflatable structures 23. In this embodiment, the two inflatable structures 23 are each located between the body 21 and the supporter 35.

[0034] As shown in Figure 3, the inflatable structure 23 has an inner circumferential surface 23a and an outer circumferential surface 23b. The inner circumferential surface 23a is an example of a first surface. The inner circumferential surface 23a of the inflatable structure 23 and the outer surface 21d of the body 21 face each other. The inner circumferential surface 23a of the inflatable structure 23 is supported by the outer surface 21d of the body 21. The outer circumferential surface 23b is located on the opposite side of the inner circumferential surface 23a. The outer circumferential surface 23b faces the supporter 35.

[0035] As shown in Figure 4, in the first embodiment, the internal space 60 has a plurality of rooms 61. That is, the internal space 60 is divided into a plurality of rooms 61. The plurality of rooms 61 are arranged in the circumferential direction and partitioned from one another. Each of the plurality of rooms 61 is located between the body 21 and the arm 42 of a corresponding arm unit 22.

[0036] The inflatable structure 23 can be expanded by filling multiple chambers 61 within its internal space 60 with gas. In other words, the portion of the inflatable structure 23 surrounding the gas-filled chambers 61 expands.

[0037] The inflatable structure 23 can be contracted by releasing gas from multiple chambers 61 within its internal space 60. In other words, the portion of the inflatable structure 23 surrounding the chambers 61 from which the gas has been released contracts.

[0038] The inflatable structure 23 is made of, for example, polyvinyl chloride (PVC), urethane nylon polyamide, nylon, polyurethane, or fiber-reinforced rubber. The inflatable structure 23 may also be made of other materials. PVC is inexpensive, flexible, and elastically stretchable. Urethane nylon polyamide is less elastically stretchable, maintains its shape well, and is tear-resistant.

[0039] As shown in Figure 2, the four restraint plates 24 are each formed in a plate shape and arranged substantially perpendicular to the axial direction, and protrude radially outward from the outer surface 21d of the body 21. For example, the restraint plates 24 are attached to the body 21 by screws. The four restraint plates 24 are spaced apart from each other in the axial direction. The axial direction is along the outer surface 21d.

[0040] As shown in Figure 4, each of the four restraint plates 24 has an outer edge 24a. The outer edge 24a is the radially outer end of the restraint plate 24. Each of the four restraint plates 24 is provided with a plurality of notches 65. The number of notches 65 in each restraint plate 24 is equal to, for example, the number of arms 42. Note that the number of notches 65 is not limited to this example.

[0041] The four cutouts 65 are arranged at substantially equal intervals in the circumferential direction and open to the outer edge 24a. In the circumferential direction, the width of the cutout 65 is larger than the width of the arm 42. The arm 42 extends through the cutout 65 when rotated maximally in the closing direction Daf.

[0042] As shown in FIG. 2, one inflatable structure 23 is located between two of the four restraint plates 24. The other inflatable structure 23 is located between the other two of the four restraint plates 24. The two inflatable structures 23 each contact two restraint plates 24. Note that the inflatable structure 23 may be temporarily separated from the restraint plate 24.

[0043] The band 25 is made of an elastomer such as, for example, synthetic rubber. One band 25 surrounds one inflatable structure 23. The other band 25 surrounds the other inflatable structure 23. When the inflatable structure 23 expands, the band 25 biases the inflatable structure 23 radially inward by an elastic force.

[0044] The camera 26 is, for example, a digital video camera. The camera 26 is, for example, housed in the insertion hole 29 of the body 21 facing the forward direction Dxf and held by the body 21. The camera 26 may be located outside the insertion hole 29.

[0045] The sensor 27 is, for example, an acceleration sensor, a gyro sensor, or an inclination sensor. The sensor 27 is not limited to this example. The mobile robot 11 may have a plurality of sensors 27. The sensor 27 detects information related to the posture of the mobile robot 11 such as, for example, acceleration and angular velocity. The sensor 27 is, for example, disposed inside the insertion hole 29. Note that the sensor 27 may be located outside the insertion hole 29.

[0046] As shown in FIG. 1, the cable 12 has a plurality of wirings 71 and a plurality of tubes 72. FIG. 1 schematically shows the wirings 71 and the tubes 72 alone. Each of the plurality of wirings 71 is, for example, electrically connected to a corresponding motor 47. As shown in FIG. 4, each of the plurality of tubes 72 is connected to a corresponding chamber 61 of the inflatable structure 23.

[0047] The plurality of wirings 71 and the plurality of tubes 72 are, for example, bundled to form the cable 12, and extend through the insertion hole 29 of the body 21. For example, the cable 12 extends rearward in the Dxb direction from the body 21. Note that the cable 12 is not limited to this example.

[0048] The mobile robot 11 may further accommodate other components in the insertion hole 29. For example, various tools such as lights, drills, cutters, and arms are accommodated in the insertion hole 29. The various tools may be located outside the body 21. Also, the mobile robot 11 may, for example, accommodate the collected sample inside the insertion hole 29.

[0049] As shown in FIG. 1, the pressurizing device 13, the plurality of regulators 14, the plurality of control valves 15, the decompression device 16, the control device 17, the display device 18, and the input device 19 are separated from the mobile robot 11. The mobile robot 11 moves relative to the pressurizing device 13, the plurality of regulators 14, the plurality of control valves 15, the decompression device 16, the control device 17, the display device 18, and the input device 19.

[0050] The pressurizing device 13, the plurality of regulators 14, the plurality of control valves 15, the decompression device 16, the control device 17, the display device 18, and the input device 19 remotely control the mobile robot 11. Note that the mobile robot 11 may have at least one of the pressurizing device 13, the plurality of regulators 14, the plurality of control valves 15, the decompression device 16, and the control device 17. When the mobile robot 11 has the pressurizing device 13, the mobile robot 11 may further have various components such as an air cylinder. In this case, the tube 72 may be omitted.

[0051] The pressurizing device 13 is connected to the plurality of tubes 72 via the plurality of regulators 14 and the plurality of control valves 15. The pressurizing device 13 is, for example, a compressor. The pressurizing device 13 can send gas to the plurality of chambers 61 of the inflatable structure 23 through the plurality of regulators 14, the plurality of control valves 15, and the plurality of tubes 72, and increase the pressure of the plurality of chambers 61.

[0052] Each of the regulators 14 is installed between the pressurizing device 13 and a corresponding chamber 61. Each regulator 14 adjusts the pressure in the chamber 61, for example, by partially releasing the gas sent from the pressurizing device 13 to the chamber 61. In this way, the multiple regulators 14 can individually adjust the pressure in multiple chambers 61.

[0053] The multiple control valves 15 are, for example, three-way valves. Each of the multiple control valves 15 connects, for example, one of the multiple regulators 14 to a corresponding pressure reducing device 16 to a corresponding tube 72. Each of the multiple control valves 15 can switch between a state in which the regulator 14 and tube 72 are connected, and a state in which the pressure reducing device 16 and tube 72 are connected.

[0054] The pressure reducing device 16 is connected to a plurality of tubes 72 via a plurality of control valves 15. The pressure reducing device 16 is, for example, a vacuum pump. The pressure reducing device 16 can suck gas from a plurality of chambers 61 of the inflatable structure 23 through the plurality of control valves 15 and the plurality of tubes 72, thereby reducing the pressure in the plurality of chambers 61.

[0055] The control device 17 is a computer comprising, for example, a processing unit such as a CPU (central processing unit), a storage device such as ROM (read-only memory) and RAM (random access memory), and an external storage device such as an HDD (hard disk drive) and a CD drive. However, the control device 17 is not limited to this example.

[0056] The control device 17 is electrically connected to the camera 26, the sensor 27, and the motors 47 via a plurality of wires 71. The control device 17 acquires video data from the camera 26. The control device 17 acquires data related to the posture of the mobile robot 11 from the sensor 27. The control device 17 further includes, for example, a driver for driving the motors 47. The control device 17 drives the motors 47 individually.

[0057] The control device 17 is electrically connected to the pressurizing device 13, regulator 14, control valve 15, and depressurizing device 16. The control device 17 controls the pressurizing device 13, regulator 14, control valve 15, and depressurizing device 16, for example, by operator operation or by calculations of a program based on video data acquired from the camera 26 and data related to the posture of the mobile robot 11 acquired from the sensor 27. If the mobile robot 11 has multiple sensors 27, the control device 17 may integrate and process multiple data acquired from the multiple sensors 27.

[0058] The display device 18 and the input device 19 are connected to the control device 17. The display device 18 displays, for example, the image from the camera 26 acquired by the control device 17, and the posture of the mobile robot 11 calculated by the control device 17 based on the detection results of the sensor 27. The input device 19 receives input for operation to the control device 17.

[0059] For example, when multiple control valves 15 connect multiple regulators 14 and multiple tubes 72, the pressurizing device 13 sends gas to multiple chambers 61 of the inflatable structure 23 through the multiple regulators 14, multiple control valves 15, and multiple tubes 72. As a result, the inflatable structure 23 expands against the elastic force of the band 25.

[0060] As shown in Figure 3, the inflatable structure 23, upon expansion, presses against the outer surface 21d of the body 21 and the inner surface 35b of the supporter 35. That is, upon expansion, the inflatable structure 23 biases the arm 42 in the opening direction Dau relative to the body 21 via the supporter 35. As a result, the arm 42 rotates in the opening direction Dau against the elastic force of the torsion coil spring 51, and the traveling device 44 moves away from the body 21. The supporter 35 is bent at its circumferential end, allowing it to efficiently receive the expanding inflatable structure 23.

[0061] The expanding inflatable structure 23 comes into contact with two restraint plates 24. The two restraint plates 24 restrict the axial expansion of the inflatable structure 23. As a result, the inflatable structure 23 expands efficiently in the radial direction, pressing against the inner surface 35b of the supporter 35.

[0062] The supporter 35 rotates around the central axis Axs relative to the arm 42 as it is pushed by the inflatable structure 23. As a result, the outer surface 21d of the body 21 and the inner surface 35b of the supporter 35 become closer to parallel. Note that the supporter 35 does not need to rotate relative to the arm 42, nor do the outer surface 21d of the body 21 and the inner surface 35b of the supporter 35 need to be parallel. Furthermore, as the supporter 35 rotates around the central axis Axs relative to the arm 42, the arm 42 enters the notch 55 of the supporter 35. At this time, the inflatable structure 23 expands so as to wrap around the arm 42, and continues to contact the portion of the supporter 35 that is circumferentially adjacent to the notch 55. As a result, the supporter 35 can continue to rotate so that the outer surface 21d of the body 21 and the inner surface 35b of the supporter 35 become closer to parallel, and comes to rest at a position (angle) where the forces are balanced.

[0063] On the other hand, when the multiple control valves 15 connect the pressure reducing device 16 to the multiple tubes 72, the pressure reducing device 16 draws gas from the multiple chambers 61 of the inflatable structure 23 through the multiple control valves 15 and the multiple tubes 72. As a result, the inflatable structure 23 contracts. In addition, the elastic force of the band 25 promotes the contraction of the inflatable structure 23.

[0064] As the inflatable structure 23 contracts, the elastic force of the torsion coil spring 51 rotates the arm 42 in the closing direction Daf relative to the body 21. This causes the traveling device 44 to approach the body 21, and the arm 42 to enter the notch 65 of the restraint plate 24. Furthermore, the supporter 35 rotates around its central axis Axs, keeping the outer surface 21d of the body 21 and the inner surface 35b of the supporter 35 approximately parallel. In addition, the inflatable structure 23 is compressed between the body 21 and the supporter 35, and gas is discharged from the chamber 61.

[0065] As shown in Figure 1, the mobile robot 11 can move inside, for example, a pipe 100. Furthermore, the mobile robot 11 can move not only inside pipes 100, but also in narrow spaces such as holes, gaps, cracks, and inside rubble.

[0066] The inflatable structure 23 biases the arm 42 in the opening direction Dau relative to the body 21, causing the wheels 46 of the travel device 44 to come into contact with the inner surface 100a of the pipe 100. The mobile robot 11 can maintain its posture inside the pipe 100 by pressing the wheels 46 of the multiple arm units 22 against the inner surface 100a. Furthermore, the motor 47 rotates the wheels 46 of the travel device 44, causing the wheels 46 to travel along the inner surface 100a.

[0067] The piping 100 includes, for example, a vertical section 101, a T-junction 102, a curved section 103, and a gate valve 104. The mobile robot 11 can traverse the vertical section 101, the T-junction 102, the curved section 103, and the gate valve 104, for example, as follows.

[0068] The vertical path 101 extends vertically. The control device 17 controls the regulator 14 to adjust the pressure in the multiple chambers 61 of the inflatable structure 23 so that the multiple wheels 46 are pressed firmly against the inner surface 100a. Furthermore, the control device 17 drives multiple motors 47 so that the wheels 46 can travel upward on the inner surface 100a. Also, when the mobile robot 11 moves downward along the vertical path 101, the control device 17 drives multiple motors 47 so that the wheels 46 can safely decelerate the movement of the mobile robot 11. The mobile robot 11 is not limited to the vertical path 101, but can also move in the same way along passages that extend diagonally upward or diagonally downward.

[0069] Figure 5 schematically shows the movement of the mobile robot 11 in a T-junction 102 according to the first embodiment. The T-junction 102 has three interconnected passages 111, 112, and 113. For example, when the mobile robot 11 moves from passage 111 to passage 112, the control device 17 individually increases or decreases the pressure of multiple chambers 61 of the inflatable structure 23.

[0070] For example, the chamber 61 located between the body 21 and the arm 42 of one of the four front units 22F, the one closest to the passage 112, is depressurized. This causes the arm 42 to rotate in the closing direction Daf, and the traveling device 44 moves closer to the body 21. When the distance between the body 21 and the traveling device 44 reaches a desired distance, the regulator 14 maintains the pressure in the chamber 61, thereby maintaining that distance.

[0071] Meanwhile, the chamber 61 located between the body 21 and the arm 42 of the front unit 22Fb, one of the four front units 22F that is furthest from the passage 112, is pressurized. This causes the arm 42 to rotate in the opening direction Dau, and the traveling device 44 moves away from the body 21. When the distance between the body 21 and the traveling device 44 reaches the desired distance, the regulator 14 maintains the pressure in the chamber 61, thereby maintaining that distance.

[0072] The control device 17 controls multiple regulators 14 to keep the running gears 44 of the four front units 22F in contact with the inner surface 100a of the piping 100. Furthermore, the control device 17 drives the motor 47 of the front unit 22Fa to move the wheels 46 backward on the inner surface 100a. The control device 17 also drives the motor 47 of the front unit 22Fb to move the wheels 46 forward on the inner surface 100a. As a result, the front end surface 21a of the body 21 approaches the passage 112.

[0073] Furthermore, the chamber 61 located between the body 21 and the arm 42 of one of the four rear units 22B, specifically the one closest to the passage 112, is pressurized. This causes the arm 42 to rotate in the opening direction Dau, moving the travel device 44 away from the body 21. When the distance between the body 21 and the travel device 44 reaches the desired distance, the regulator 14 maintains the pressure in the chamber 61, thereby maintaining that distance.

[0074] Meanwhile, the chamber 61 located between the body 21 and the arm 42 of the rear unit 22Bb, one of the four rear units 22B that is furthest from the passage 112, is depressurized. This causes the arm 42 to rotate in the closing direction Daf, and the traveling device 44 moves closer to the body 21. When the distance between the body 21 and the traveling device 44 reaches the desired distance, the regulator 14 maintains the pressure in the chamber 61, thereby maintaining that distance.

[0075] The control device 17 controls multiple regulators 14 to keep the running gears 44 of the four rear units 22B in contact with the inner surface 100a of the piping 100. Furthermore, the control device 17 drives the motor 47 of the rear unit 22Ba to move the inner surface 100a backward against the wheels 46. The control device 17 also drives the motor 47 of the rear unit 22Bb to move the inner surface 100a forward against the wheels 46. As a result, the rear end surface 21b of the body 21 moves away from the passage 112.

[0076] As described above, the control device 17 uses the pressurizing device 13 to individually supply gas to the multiple chambers 61 through multiple tubes 72 connected to the multiple chambers 61. As a result, the inflating inflatable structure 23 individually widens the distance between the body 21 and the arms 42 of the multiple arm units 22, changing the posture of the mobile robot 11 with respect to the inner surface 100a. Furthermore, the control device 17 individually drives the travel devices 44 of the multiple arm units 22.

[0077] The mobile robot 11 can smoothly move into the passage 112 by changing its posture to face the passage 112. In addition, the mobile robot 11 can smoothly turn around the curved path 103 by changing its posture.

[0078] Furthermore, the control device 17 drives the wheels 46 of the front unit 22Fa and the rear unit 22Ba at a low speed, and drives the wheels 46 of the front unit 22Fb and the rear unit 22Bb at a high speed. This allows the mobile robot 11 to move smoothly into the passage 112.

[0079] Figure 6 is a schematic diagram showing a mobile robot 11 entering a gate valve 104 in the first embodiment. As shown in Figure 6, for example, a discontinuity (separation, non-continuous portion) 115 is provided on the inner surface 100a of the gate valve 104. The discontinuity 115 is a gap between two surfaces. Note that the discontinuity 115 may be provided in a part other than the gate valve 104, or it may be a hole, groove, or recess.

[0080] For example, if the wheel 46 becomes disconnected 115, the mobile robot 11 may become unable to move. However, the robot movement system 10 of this embodiment can control the mobile robot 11 in a way that avoids the wheel 46 becoming disconnected 115.

[0081] As shown by the dashed line in Figure 6, before the mobile robot 11 enters the gate valve 104, the pressurizing device 13 sends gas through multiple tubes 72 to multiple chambers 61, causing all the travel devices 44 of the front unit 22F and rear unit 22B to come into contact with the inner surface 100a of the piping 100. Note that the pressures in the multiple chambers 61 may be different from each other.

[0082] For example, just before the travel device 44 of the front unit 22F reaches the disconnection 115, the control device 17 controls a plurality of control valves 15 so that a plurality of chambers 61 located between the body 21 and the arm 42 of the front unit 22F are connected to the pressure reducing device 16. As a result, the transport of gas by the pressurizing device 13 to the plurality of chambers 61 located between the body 21 and the arm 42 of the front unit 22F is stopped.

[0083] Furthermore, gas is discharged from multiple chambers 61 located between the body 21 and the arm 42 of the front unit 22F. As a result, as shown by the solid line in Figure 6, the arm 42 of the front unit 22F rotates in the closing direction Daf, and the traveling device 44 moves closer to the body 21. Meanwhile, the traveling device 44 of the rear unit 22B remains in contact with the inner surface 100a.

[0084] Next, the control device 17 drives the travel device 44 of the rear unit 22B by controlling the motor 47. As a result, the mobile robot 11 moves forward Dxf, and the travel device 44 of the front unit 22F crosses the gap 115.

[0085] Figure 7 schematically shows the mobile robot 11 exiting the gate valve 104 in the first embodiment. Next, the control device 17 controls a plurality of control valves 15 so that a plurality of chambers 61 located between the body 21 and the arm 42 of the front unit 22F are connected to the regulator 14.

[0086] The pressurizing device 13 sends gas through multiple tubes 72 to multiple chambers 61 located between the body 21 and the front unit 22F. As a result, as shown by the solid line in Figure 7, the arm 42 of the front unit 22F rotates in the opening direction Dau, and the traveling device 44 comes into contact with the inner surface 100a of the piping 100.

[0087] Furthermore, the control device 17 controls multiple control valves 15 so that multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B are connected to the pressure reducing device 16. As a result, the transport of gas by the pressurizing device 13 to the multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B is stopped.

[0088] Furthermore, gas is discharged from multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B. As a result, as shown by the solid line in Figure 7, the arm 42 of the rear unit 22B rotates in the closing direction Daf, and the traveling device 44 moves closer to the body 21.

[0089] Next, the control device 17 drives the travel device 44 of the front unit 22F by controlling the motor 47. As a result, the mobile robot 11 moves forward Dxf, and the travel device 44 of the rear unit 22B crosses the gap 115.

[0090] Next, the control device 17 controls multiple control valves 15 so that multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B are connected to the regulator 14. As a result, the pressurizing device 13 sends gas to the multiple chambers 61 located between the body 21 and the rear unit 22B through multiple tubes 72. As shown by the dashed line in Figure 7, the arm 42 of the rear unit 22B rotates in the opening direction Dau, and the traveling device 44 comes into contact with the inner surface 100a of the piping 100.

[0091] As described above, by having the traveling device 44 avoid the gap 115, the mobile robot 11 can smoothly cross the gap 115. After the mobile robot 11 crosses the gap 115, all the traveling devices 44 of the front unit 22F and the rear unit 22B come into contact with the inner surface 100a of the piping 100. Therefore, the mobile robot 11 can continue to move smoothly even after crossing the gap 115.

[0092] In the operation of the mobile robot 11 described above, the inflation or deflation of the chamber 61 of the inflatable structure 23 corresponding to each arm unit 22 is controlled manually or automatically. That is, while the mobile robot 11 is moving, the control device 17 obtains video data acquired from the camera 26 and data related to the posture of the mobile robot 11 acquired from the sensor 27. For example, the control device 17 outputs this data to the display device 18, and the operator operates the input device 19 based on this data. The control device 17 may inflate or deflate multiple chambers 61 based on this operation. Alternatively, the control device 17 may automatically inflate or deflate multiple chambers 61 by calculations of a program based on this data. In this case, the wiring 71 may be omitted because the mobile robot 11 has a built-in control device 17 and a battery. The mobile robot 11 may also have an antenna and a battery and be controlled by a wireless signal from the control device 17. In this case as well, the wiring 71 may be omitted.

[0093] In the robotic mobile system 10 according to the first embodiment described above, each of the multiple arm units 22 has a traveling device 44 and an arm 42. The traveling device 44 is configured to travel on the inner surface 100a that it is in contact with. The arm 42 supports the traveling device 44 and is movable relative to the body 21 so that the distance between the body 21 and the traveling device 44 changes. The multiple arm units 22 are arranged around the body 21. An inflatable structure 23 is provided with an internal space 60. The inflatable structure 23 is located between the body 21 and the arm 42 and is configured to inflate when the internal space 60 is filled with gas.

[0094] The inflatable structure 23 expands between the body 21 and the arm 42 when gas is filled into its internal space 60. As a result, the expanding inflatable structure 23 pushes the arm 42, increasing the distance between the body 21 and the travel device 44. When the travel device 44 comes into contact with the inner surface 100a, the inflatable structure 23 can press the arm 42 against the travel device 44. For example, when the mobile robot 11 is located in a narrow space such as the inside of a pipe 100, the inflatable structure 23 can press the travel devices 44 of the multiple arm units 22 against the inner surface 100a of the pipe 100, thereby maintaining the posture of the mobile robot 11. On the other hand, when the gas is discharged from the internal space 60 of the inflatable structure 23, the force pushing the arm 42 is reduced. As a result, the arm 42 can move in a way that reduces the distance between the body 21 and the travel device 44, and consequently, the travel device 44 can avoid, for example, any irregularities inside the pipe 100. As described above, the mobile robot 11 can adjust the distance between the body 21 and the travel device 44 by expanding and contracting the inflatable structure 23. Therefore, the mobile robot 11 can be made lighter and smaller compared to, for example, a case where the distance between the body 21 and the travel device 44 is adjusted by an air cylinder, and consequently, the load that can be carried (e.g., the weight of a tool) can be increased. Furthermore, since the expanded inflatable structure 23 is filled with gas, it acts as an elastic body between the body 21 and the arm 42. Therefore, the expanded inflatable structure 23 can absorb vibrations like a suspension by elastically deforming. Consequently, the mobile robot 11 can reduce vibrations from the outside and shocks when passing over uneven surfaces compared to, for example, a case where the arm 42 is moved by a motor. Also, an air cylinder that expands and contracts using gas expands and contracts only in the longitudinal direction of the air cylinder. On the other hand, since the expanded inflatable structure 23 can deform freely, it can absorb vibrations better than an air cylinder.

[0095] The running gear 44 has wheels 46. The arm 42 has a first mounting portion 42a and a second mounting portion 42b. The first mounting portion 42a is attached to the body 21 so as to be rotatable around the central axis Axa. The second mounting portion 42b is spaced apart from the first mounting portion 42a and is attached to the running gear 44. The arm 42 is configured to move the running gear 44 away from the body 21 by rotating in the opening direction Dau around the central axis Axa. The arm 42 is configured to move the running gear 44 closer to the body 21 by rotating in the closing direction Daf, opposite to the opening direction Dau. The inflatable structure 23, by inflating, biases the arm 42 in the opening direction Dau relative to the body 21. As a result, the mobile robot 11 can stabilize its posture compared to when the arm 42 is not attached to the body 21.

[0096] Each of the multiple arm units 22 has a biasing member 33 that biases the arm 42 in the closing direction Daf relative to the body 21. For example, when the supply of gas to the inflatable structure 23 is stopped, the biasing member 33 rotates the arm 42 in the closing direction Daf relative to the body 21, and the distance between the body 21 and the arm 42 decreases. The inflatable structure 23 is compressed between the body 21 and the arm 42, and the gas in the internal space 60 is expelled. As described above, the mobile robot 11 can reduce the distance between the body 21 and the traveling device 44 by stopping the supply of gas to the internal space 60, thereby contracting the inflatable structure 23.

[0097] The biasing member 33 has a torsion coil spring 51. One end of the torsion coil spring 51 is supported by the body 21, and the other end is supported by the first mounting portion 42a. This allows the mobile robot 11 to bias the arm 42 in the closing direction Daf by the small biasing member 33, thereby enabling miniaturization. In addition, the biasing member 33 can be prevented from interfering with other parts such as the inflatable structure 23.

[0098] Each of the arm units 22 has a supporter 35 attached to the arm 42 so as to be rotatable around a central axis Axs parallel to the central axis Axa. The inflatable structure 23 is located between the body 21 and the supporter 35.

[0099] The inflatable structure 23, when it expands, pushes the supporter 35, thereby pushing the arm 42 through the supporter 35. The supporter 35 can rotate around the central axis Axs along the outer circumferential surface 23b of the inflatable structure 23 that is in contact with the supporter 35. That is, even if the arm 42 rotates around the central axis Axa, the supporter 35 can maintain a wide contact area between the supporter 35 and the inflatable structure 23. Therefore, the inflatable structure 23 can efficiently rotate the arm 42.

[0100] A notch 55 is provided in the supporter 35. The supporter 35 is configured to rotate around the central axis Axs relative to the arm 42, causing the arm 42 to enter the notch 55. Therefore, even if the supporter 35 rotates around the central axis Axs relative to the arm 42, interference with the arm 42 can be suppressed.

[0101] The body 21 has an outer surface 21d facing multiple arm units 22 and an inflatable structure 23. Two restraint plates 24 are spaced apart from each other in the axial direction along the outer surface 21d. The inflatable structure 23 is located between the two restraint plates 24. The inflatable structure 23 is restricted from expanding in the axial direction by contacting at least one of the two restraint plates 24. On the other hand, the inflatable structure 23 can expand in the direction facing the outer surface 21d. That is, the mobile robot 11 guides the expansion of the inflatable structure 23 with the two restraint plates 24, allowing the inflatable structure 23 to efficiently push the arms 42, and consequently stabilizing the movement of the mobile robot 11. Furthermore, this suppresses unnecessary expansion of the inflatable structure 23, for example, in the axial direction, making it possible to miniaturize and lighten the inflatable structure 23. The restraint plates 24 are set to dimensions (width, height, and position) that achieve the above effects.

[0102] A notch 65 is provided in the restraint plate 24. The arm 42 is configured to enter the notch 65 when it rotates in the closing direction Daf relative to the body 21. In this way, by providing the notch 65 in the restraint plate 24, interference between the arm 42 and the restraint plate 24 when the arm 42 rotates in the closing direction Daf is suppressed, while the restraint plate 24 can limit the axial expansion of the inflatable structure 23. Therefore, the mobile robot 11 can be made smaller and move efficiently in narrow spaces.

[0103] The inflatable structure 23 surrounds the body 21. That is, the body 21 is positioned inside the annular inflatable structure 23. This prevents the inflatable structure 23 from detaching from the body 21.

[0104] The internal space 60 has multiple rooms 61 that are separated from each other. Therefore, the mobile robot 11 can adjust the expansion of the inflatable structure 23 by individually filling the multiple rooms 61 with gas.

[0105] The tube 72 is connected to the inflatable structure 23. The pressurizing device 13 sends gas into the internal space 60 through the tube 72. The mobile robot 11 is configured to move relative to the pressurizing device 13. In other words, the pressurizing device 13 is not mounted on the mobile robot 11. Therefore, the robot movement system 10 makes the mobile robot 11 lighter and smaller, and consequently increases the load that the mobile robot 11 can carry.

[0106] The depressurization device 16 sucks gas from the internal space 60. By sucking gas from the internal space 60, the depressurization device 16 causes the inflatable structure 23 to contract, allowing the traveling device 44 to approach the body 21. In other words, the robotic mobile system 10 can prevent the inflatable structure 23 from being prevented from approaching the body 21 after the pressurization device 13 stops increasing the pressure in the internal space 60.

[0107] The depressurization device 16 is configured to draw gas from the internal space 60 through the tube 72. In other words, the depressurization device 16 is not mounted on the mobile robot 11. Therefore, the robot movement system 10 can make the mobile robot 11 lighter and smaller, and consequently increase the load that the mobile robot 11 can transport.

[0108] A pressurizing device 13, located away from the mobile robot 11, sends gas individually to the multiple chambers 61 through multiple tubes 72 connected to the multiple chambers 61. As a result, the inflating inflatable structure 23 individually increases the distance between the body 21 and the arms 42 of the multiple arm units 22, changing the posture of the mobile robot 11 relative to the inner surface 100a. Therefore, the mobile robot 11 can change its posture and direction of travel. For example, the mobile robot 11 can move in a desired direction at a T-junction 102.

[0109] The control device 17 drives the travel devices 44 of multiple arm units 22 individually. This allows the mobile robot 11 to change its direction of travel. For example, the mobile robot 11 can move in a desired direction at a T-junction 102. Because the mobile robot 11 can change its posture, it can move smoothly in a desired direction.

[0110] A pressurizing device 13, located away from the mobile robot 11, sends gas to the multiple chambers 61 through multiple tubes 72 connected to the multiple chambers 61. As a result, the travel devices 44 of the rear unit 22B and the front unit 22F, located away from the rear unit 22B in the direction of travel of the mobile robot 11 (forward direction Dxf), are brought into contact with the inner surface 100a. Furthermore, the transport of gas by the pressurizing device 13 to one of the multiple chambers 61 located between the body 21 and the arm 42 of the front unit 22F is stopped. Then, the travel device 44 is driven by the control device 17, causing the mobile robot 11 to move forward in the Dxf direction, and the travel device 44 of the front unit 22F crosses the gap 115 provided on the inner surface 100a. Furthermore, gas is sent by the pressurizer 13 to one of the multiple chambers 61 located between the body 21 and the arm 42 of the front unit 22F, causing the travel device 44 of the front unit 22F to come into contact with the inner surface 100a. Furthermore, the transport of gas by the pressurizer 13 to one of the multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B is stopped. Furthermore, the travel device 44 is driven by the control device 17, causing the mobile robot 11 to move forward in the direction Dxf, and the travel device 44 of the rear unit 22B to cross the gap 115. Furthermore, gas is sent by the pressurizer 13 to one of the multiple chambers 61 located between the body 21 and the arm 42 of the rear unit 22B, causing the travel device 44 of the rear unit 22B to come into contact with the inner surface 100a. As a result, the mobile robot 11 can cross the gap 115 provided on the inner surface 100a. In other words, the mobile robot 11 can prevent the driving device 44 from becoming disconnected 115, which would make it difficult to move.

[0111] (Second Embodiment) The second embodiment will be described below with reference to Figure 8. In the following descriptions of the multiple embodiments, components that have the same function as those already described will be denoted by the same reference numerals as those previously described components, and their descriptions may be omitted. Furthermore, multiple components denoted by the same reference numerals do not necessarily share all functions and properties, and may have different functions and properties depending on the embodiment.

[0112] Figure 8 is a schematic cross-sectional view showing a mobile robot 11 according to the second embodiment. As shown in Figure 8, each of the two inflatable structures 23 of the second embodiment has a plurality of small inflatable structures 200. The plurality of small inflatable structures 200 is an example of a plurality of individual inflatable structures, and is also an example of a plurality of inflatable structures.

[0113] Each of the multiple small inflatable structures 200 is positioned between the body 21 and a corresponding arm 42 from among the multiple arm units 22. Each of the multiple small inflatable structures 200 is formed in the shape of a bag, for example, from a membrane or cloth. Therefore, each of the multiple small inflatable structures 200 is provided with an internal space 205.

[0114] The multiple small inflatable structures 200 include multiple lower inflatable structures 200L and multiple upper inflatable structures 200U. The lower inflatable structure 200L is an example of a first individual inflatable structure and is at least one of the multiple small inflatable structures 200. The upper inflatable structure 200U is an example of a second individual inflatable structure and is at least one other of the multiple small inflatable structures 200.

[0115] One lower inflatable structure 200L and one upper inflatable structure 200U are located between the body 21 and the arm 42 of one arm unit 22. The lower inflatable structure 200L is located between the body 21 and the upper inflatable structure 200U. That is, the lower inflatable structure 200L and the upper inflatable structure 200U are stacked radially. The plurality of small inflatable structures 200 may further include inflatable structures located at least one of the following locations: between the lower inflatable structure 200L and the upper inflatable structure 200U, between the body 21 and the lower inflatable structure 200L, and between the upper inflatable structure 200U and the arm 42. The band 25 surrounds the plurality of upper inflatable structures 200U.

[0116] The lower inflatable structure 200L is attached to the body 21, for example, by adhesive or hook-and-loop fasteners. This prevents the inflatable structure 23 from falling off the body 21. The upper inflatable structure 200U may be attached to the supporter 35.

[0117] The internal space 205 of the lower inflatable structure 200L and the internal space 205 of the upper inflatable structure 200U are in communication with each other through a connection port 206. The connection port 206 is, for example, a small hole that causes pressure loss in the movement of gas between the internal space 205 of the lower inflatable structure 200L and the internal space 205 of the upper inflatable structure 200U.

[0118] Tube 72 is connected to the internal space 205 of the lower inflatable structure 200L. That is, tube 72 is connected to the internal space 205 of the upper inflatable structure 200U through the internal space 205 of the lower inflatable structure 200L and the connection port 206.

[0119] The pressurizing device 13 fills the internal space 205 of the lower inflatable structure 200L with gas through the tube 72. This causes the lower inflatable structure 200L to expand. Furthermore, gas flows from the internal space 205 of the lower inflatable structure 200L into the internal space 205 of the upper inflatable structure 200U through the connection port 206, causing the upper inflatable structure 200U to expand.

[0120] When at least one of the lower inflatable structure 200L and the upper inflatable structure 200U inflates, the lower inflatable structure 200L presses against the outer surface 21d of the body 21, and the upper inflatable structure 200U presses against the inner surface 35b of the supporter 35. In other words, when the multiple small inflatable structures 200 inflate, they bias the arms 42 in the opening direction Dau relative to the body 21 via the supporter 35. As a result, the arms 42 rotate in the opening direction Dau against the elastic force of the torsion coil spring 51, and the traveling device 44 moves away from the body 21.

[0121] The decompression device 16 draws gas from the internal space 205 of the lower inflatable structure 200L through the tube 72. This causes the lower inflatable structure 200L to contract. Furthermore, gas is drawn from the internal space 205 of the upper inflatable structure 200U to the decompression device 16 through the connection port 206 and the internal space 205 of the lower inflatable structure 200L, causing the upper inflatable structure 200U to contract.

[0122] When at least one of the lower inflatable structure 200L and the upper inflatable structure 200U is deflated, the elastic force of the torsion coil spring 51 causes the arm 42 to rotate in the closing direction Daf relative to the body 21. As a result, the traveling device 44 moves closer to the body 21.

[0123] The mobile robot 11 of the second embodiment, like the first embodiment, can traverse the vertical path 101, T-junction 102, curved path 103, and gate valve 104 of the piping 100.

[0124] For example, gas is individually supplied from the pressurizing device 13 to the internal spaces 205 of multiple small inflatable structures 200 through multiple tubes 72. As a result, the distance between the body 21 and the arms 42 of the multiple arm units 22 is individually increased by the inflating multiple small inflatable structures 200.

[0125] As a result, the posture of the mobile robot 11 relative to the inner surface 100a of the pipe 100 changes. By changing its posture, the mobile robot 11 can move along the T-junction 102 in the desired direction and smoothly turn the curved road 103.

[0126] Furthermore, for example, gas is supplied from the pressurizing device 13 to multiple small inflatable structures 200 through multiple tubes 72. As a result, the travel devices 44 of the rear unit 22B and the front unit 22F are brought into contact with the inner surface 100a of the piping 100.

[0127] Next, the gas transport by the pressurizer 13 to one of the multiple small inflatable structures 200, located between the body 21 and the arm 42 of the front unit 22F, is stopped. As a result, the arm 42 of the front unit 22F rotates in the closing direction Daf, and the traveling device 44 moves away from the inner surface 100a.

[0128] Next, the control device 17 drives the travel device 44 by controlling the motor 47, causing the mobile robot 11 to move forward in the Dxf direction. As a result, the travel device 44 of the forward unit 22F crosses the gap 115.

[0129] Next, gas is sent from the pressurizing device 13 to one of the multiple small inflatable structures 200 located between the body 21 and the front unit 22F. As a result, the arm 42 of the front unit 22F rotates in the opening direction Dau, and the traveling device 44 comes into contact with the inner surface 100a.

[0130] Next, the gas transport by the pressurizer 13 to one of the multiple small inflatable structures 200, located between the body 21 and the arm 42 of the rear unit 22B, is stopped. As a result, the arm 42 of the rear unit 22B rotates in the closing direction Daf, and the traveling device 44 moves away from the inner surface 100a.

[0131] Next, the control device 17 drives the motor 47 to move the mobile robot 11 forward in the Dxf direction. As a result, the travel device 44 of the rear unit 22B crosses the gap 115.

[0132] Next, gas is sent from the pressurizing device 13 to one of the multiple small inflatable structures 200 located between the body 21 and the rear unit 22B. As a result, the arm 42 of the rear unit 22B rotates in the opening direction Dau, and the traveling device 44 comes into contact with the inner surface 100a.

[0133] As described above, the travel device 44 of the front unit 22F and the travel device 44 of the rear unit 22B sequentially avoid the gap 115. This allows the mobile robot 11 to smoothly cross the gap 115.

[0134] In the robot mobile system 10 of the second embodiment described above, the inflatable structure 23 has a plurality of small inflatable structures 200. Each of the plurality of small inflatable structures 200 is positioned between the body 21 and one of the arms 42 of the plurality of arm units 22. This allows the mobile robot 11 to inflate the inflatable structure 23 more efficiently than when one large inflatable structure 23 is positioned between the body 21 and the arms 42 of the plurality of arm units 22, and also improves the design freedom (flexibility) of the mobile robot 11.

[0135] The multiple small inflatable structures 200 include a lower inflatable structure 200L and an upper inflatable structure 200U, which are positioned between the body 21 and one of the arms 42 of the multiple arm units 22. The lower inflatable structure 200L is positioned between the body 21 and the upper inflatable structure 200U. This allows the mobile robot 11 to inflate the inflatable structures 23 more efficiently than if one large inflatable structure 23 were positioned between the body 21 and the arms 42 of the multiple arm units 22. Furthermore, by inflating the lower inflatable structure 200L and the upper inflatable structure 200U in sequence, the mobile robot 11 can more easily adjust the position of the travel device 44 in stages.

[0136] (Third Embodiment) The third embodiment will be described below with reference to Figure 9. Figure 9 is a schematic side view showing the mobile robot 11 according to the third embodiment. As shown in Figure 9, the biasing member 33 of the third embodiment has two elastic bodies 301. The two elastic bodies 301 are, for example, tension springs. Note that the elastic bodies 301 may be other elastic materials such as synthetic rubber.

[0137] One end of the elastic body 301 is attached to the body 21. The other end of the elastic body 301 is attached to the arm 42 at a position spaced apart from the central axis Axa. For example, the elastic body 301 is attached to the arm 42 near the second mounting portion 42b.

[0138] When the arm 42 rotates in the opening direction Dau, the elastic body 301 is pulled. This causes the elastic body 301 to bias the arm 42 in the closing direction Daf. When gas is drawn from the inflatable structure 23 by the decompression device 16, the elastic force of the elastic body 301 promotes the contraction of the inflatable structure 23.

[0139] In the robot movement system 10 of the third embodiment described above, the biasing member 33 has an elastic body 301 with one end attached to the body 21 and the other end attached to the arm 42 at a position spaced apart from the central axis Axa. The elastic body 301 pulls the arm 42 toward the body 21, thereby biasing the arm 42 in the closing direction Daf relative to the body 21. The elastic body 301 can pull the arm 42 at a position spaced apart from the central axis Axa. That is, because the distance between the fulcrum and the point of force application is increased, the elastic body 301 can deflate the inflatable structure 23 with less force using the arm 42.

[0140] (Fourth Embodiment) The fourth embodiment will be described below with reference to Figure 10. Figure 10 is a schematic side view showing the mobile robot 11 according to the fourth embodiment. As shown in Figure 10, the biasing member 33 of the fourth embodiment has an elastic body 401. The elastic body 401 is, for example, a tension spring. The elastic body 401 may be other elastic materials such as synthetic rubber.

[0141] One end of the elastic body 401 is attached to one of the arm units 22, at a position spaced apart from the central axis Axa. The other end of the elastic body 401 is attached to another arm 42 of the arm units 22, at a position spaced apart from the central axis Axa. For example, the elastic body 401 is attached to the arm 42 near the second attachment portion 42b.

[0142] When the arms 42 of the multiple arm units 22 rotate in the opening direction Dau, the distance between the second mounting portion 42b of one arm 42 and the second mounting portion 42b of another arm 42 increases. As a result, the elastic body 401 is pulled between the two arms 42.

[0143] The elastic body 401 pulls the second mounting portion 42b of one arm 42 and the second mounting portion 42b of the other arm 42 by elastic force. As a result, the elastic body 401 biases the arms 42 in the closing direction Daf.

[0144] When gas is drawn from the inflatable structure 23 by the decompression device 16, the elastic force of the elastic body 401 promotes the contraction of the inflatable structure 23.

[0145] In the robot movement system 10 of the fourth embodiment described above, the biasing member 33 has an elastic body 401. One end of the elastic body 401 is attached to one arm 42 of the plurality of arm units 22 at a position spaced away from the central axis Axa. The other end of the elastic body 401 is attached to another arm 42 of the plurality of arm units 22 at a position spaced away from the central axis Axa. The elastic body 401 pulls the arms 42 of the two arm units 22, thereby biasing the arms 42 in the closing direction Daf relative to the body 21. The elastic body 401 can pull the arms 42 at a position spaced away from the central axis Axa. That is, because the distance between the fulcrum and the point of force application is increased, the elastic body 401 can deflate the inflatable structure 23 with less force using the arms 42.

[0146] (Fifth Embodiment) The fifth embodiment will be described below with reference to Figure 11. Figure 11 is a cross-sectional view showing a part of the mobile robot 11 with the arm unit 22 of the fifth embodiment deployed. As shown in Figure 11, the arm unit 22 of the fifth embodiment does not have an intermediate hinge 34 and a supporter 35. However, the arm unit 22 may have an intermediate hinge 34 and a supporter 35.

[0147] The inflatable structure 23 of the fifth embodiment has an outer circumferential surface 501 instead of an outer circumferential surface 23b. The outer circumferential surface 501 is an example of a second surface. The outer circumferential surface 501 is substantially equal to the outer circumferential surface 23b, except as described below.

[0148] When the inflatable structure 23 is inflated to its maximum extent, the outer surface 501 is formed in a substantially conical shape (frustum shape) that tapers in the forward direction Dxf. That is, when the inflatable structure 23 is inflated to its maximum extent, the outer surface 501 is inclined with respect to the outer surface 21d such that the distance between the outer surface 501 and the outer surface 21d of the body 21 decreases toward the first mounting portion 42a.

[0149] The outer circumferential surface 501 is in direct contact with the arm 42. That is, the outer circumferential surface 501 supports the arm 42. Other components may be interposed between the outer circumferential surface 501 and the arm 42. The inflatable structure 23 can be inflated and deflated such that the angle between the outer surface 21d of the body 21 and the outer circumferential surface 501 is approximately the same as the angle between the outer surface 21d of the body 21 and the arm 42.

[0150] In the fifth embodiment of the robotic mobile system 10 described above, the body 21 has an outer surface 21d facing a plurality of arm units 22 and an inflatable structure 23. The inflatable structure 23 has an inner circumferential surface 23a supported by the outer surface 21d and an outer circumferential surface 501 located on the opposite side of the inner circumferential surface 23a. When the inflatable structure 23 is inflated to its maximum extent, the outer circumferential surface 501 inclins with respect to the outer surface 21d such that the distance between the outer circumferential surface 501 and the outer surface 21d decreases toward the first mounting portion 42a, and supports the arm 42. That is, the outer circumferential surface 501 inclins with respect to the outer surface 21d so as to follow the arm 42 which is inclined with respect to the body 21 by being pushed by the inflatable structure 23. Therefore, the inflating inflatable structure 23 can efficiently push the arm 42.

[0151] (Sixth Embodiment) The sixth embodiment will now be described with reference to Figure 12. Figure 12 is a schematic diagram showing the robot movement system 10 according to the sixth embodiment. As shown in Figure 12, the robot movement system 10 of the sixth embodiment has a plurality of control valves 601 and a plurality of pressure reducing devices 602 instead of a plurality of control valves 15 and a pressure reducing device 16. Figure 12 schematically shows the plurality of control valves 601 and a plurality of pressure reducing devices 602 individually. The control valves 601 and the plurality of pressure reducing devices 602 are substantially equivalent to the control valves 15 and pressure reducing devices 16, except as described below.

[0152] The multiple control valves 601 are, for example, solenoid valves. The multiple control valves 601 are provided between the multiple regulators 14 and the multiple tubes 72. The control device 17 can open and close the multiple control valves 601.

[0153] Each of the multiple pressure reducing devices 602 has an ejector 611 and three solenoid valves 612, 613, and 614. The ejector 611 is provided on the tube 72. The ejector 611 may also be provided at the end of the tube 72 and attached to the mobile robot 11.

[0154] The ejector 611 is provided with an opening connected to the pressurizing device 13 via a control valve 601 and a regulator 14, an opening connected to a chamber 61 in the internal space 60 of the inflatable structure 23, and an opening that is open to the outside. The ejector 611 generates negative pressure from the airflow supplied from the pressurizing device 13 by the Venturi effect. The ejector 611 uses this negative pressure to draw gas from the chamber 61 and discharge the gas to the outside.

[0155] Each of the solenoid valves 612, 613, and 614 is electrically connected to the control device 17, for example, through wiring 71. The control device 17 can open and close the solenoid valves 612, 613, and 614 individually.

[0156] Solenoid valve 612 is provided between ejector 611 and control valve 601. Solenoid valve 613 is provided between ejector 611 and chamber 61 of inflatable structure 23. Solenoid valve 614 is provided in the path of tube 72 that bypasses ejector 611 and solenoid valves 612 and 613 to connect control valve 601 and chamber 61.

[0157] For example, when the control device 17 inflates the inflatable structure 23, it closes solenoid valves 612 and 613 and opens solenoid valve 614. This causes the pressurizing device 13 to send gas to the multiple chambers 61 of the inflatable structure 23 through multiple regulators 14, multiple control valves 601, and multiple tubes 72. As a result, the inflatable structure 23 inflates against the elastic force of the band 25.

[0158] Meanwhile, when the inflatable structure 23 is deflated, the control device 17 opens solenoid valves 612 and 613 and closes solenoid valve 614. As a result, the pressurizing device 13 sends gas to the ejector 611 through the regulator 14, control valve 601, and tube 72.

[0159] The ejector 611 generates negative pressure through airflow, drawing gas from the corresponding chamber 61. This causes the inflatable structure 23 to contract. Additionally, the elastic force of the band 25 facilitates the contraction of the inflatable structure 23.

[0160] In the sixth embodiment of the robot mobile system 10 described above, the depressurizing device 602 has an ejector 611 provided on the tube 72 and configured to generate negative pressure by the airflow supplied from the pressurizing device 13. That is, the robot mobile system 10 can switch between expanding and contracting the inflatable structure 23 while continuously supplying gas from the pressurizing device 13. Therefore, the robot mobile system 10 can improve the efficiency of its operation. Furthermore, the distance between the depressurizing device 602 and the internal space 60 is shorter compared to the case where the depressurizing device 602 is located near the pressurizing device 13. As a result, the robot mobile system 10 can quickly suck in the gas from the internal space 60 and quickly contract the inflatable structure 23. In addition, if the tube 72 is damaged, it is suppressed that the depressurizing device 602, for example, will suck in dust and other debris from the space in which the mobile robot 11 is moving through the tube 72. Therefore, the robotic movement system 10 can prevent the tube 72 and the decompression device 602 from becoming clogged, and consequently, it can prevent any impact on the pressurization and decompression of the inflatable structure 23.

[0161] In the above embodiments, the biasing member 33 biases the arm 42 in the closing direction Daf by elastic force. However, the biasing member 33 is not limited to this example, and the arm 42 may be biased in the closing direction Daf by, for example, pressure or magnetic force.

[0162] Furthermore, in the above embodiments, the plurality of arm units 22 include four front units 22F and four rear units 22B. That is, the plurality of arm units 22 are arranged in two rows. However, the plurality of arm units 22 may be arranged in one row, or in three or more rows.

[0163] Furthermore, in the above embodiments, multiple tubes 72 are connected to multiple chambers 61 of the inflatable structure 23, or to the internal spaces 205 of multiple small inflatable structures 200. However, one chamber 61 may be connected to the pressurizing device 13 through one tube 72, and that one chamber 61 may communicate with other multiple chambers 61. Alternatively, one tube 72 may be connected to the pressurizing device 13, and that one tube 72 may be branched to connect to multiple chambers 61.

[0164] Furthermore, in the above-described embodiments, when the arms 42 rotate to their maximum extent in the closed direction Daf, all arms 42 extend from the end hinge 41 in the rearward direction Dxb. However, for example, when all arms 42 rotate to their maximum extent in the closed direction Daf, the arms 42 of the front unit 22F may extend in the rearward direction Dxb, and the arms 42 of the rear unit 22B may extend in the forward direction Dxf. In this case, for example, it is possible to prevent the wheels 46 from getting caught on uneven surfaces. That is, regardless of whether the mobile robot 11 is moving in the forward direction Dxf or the rearward direction Dxb, the arms 42 of the arm unit 22 that first interfere with the uneven surface can rotate smoothly in the closed direction Daf due to the impact of the interference with the uneven surface. Therefore, the wheels 46 can easily escape from the uneven surface.

[0165] Furthermore, when all arms 42 are rotated to their maximum extent in the closed direction Daf, the arms 42 of the front unit 22F may extend in the forward direction Dxf, and the arms 42 of the rear unit 22B may extend in the rear direction Dxb. In this case, the mobile robot 11 can shorten its overall length while increasing the distance between the wheels 46 of the front unit 22F and the wheels 46 of the rear unit 22B. This allows the mobile robot 11 to move while avoiding, for example, long gaps 115. Also, the posture of the mobile robot 11 is more stable.

[0166] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

Claims

1. A mobile robot comprising: a body; a travel device configured to travel on a contact surface; a support member that supports the travel device and is movable relative to the body such that the distance between the body and the travel device changes; a plurality of units arranged around the body; and a member having an internal space, located between the body and the support member, and configured to expand when the internal space is filled with gas.

2. The mobile robot according to claim 1, wherein the traveling device has wheels, and the support member has a first mounting portion attached to the body so as to be rotatable around a first rotation axis, and a second mounting portion attached to the traveling device and spaced apart from the first mounting portion, and is configured to move the traveling device away from the body by rotating in an opening direction around the first rotation axis, and to move the traveling device closer to the body by rotating in a closing direction opposite to the opening direction, and the member is configured to bias the support member relative to the body in the opening direction by expanding.

3. The mobile robot according to claim 2, wherein each of the plurality of units further comprises a biasing member that biases the support member relative to the body in the closing direction.

4. The mobile robot according to claim 3, wherein the biasing member has a torsion coil spring, one end of which is supported by the body and the other end of which is supported by the first mounting portion.

5. The mobile robot according to claim 3, wherein the biasing member has an elastic body with one end attached to the body and the other end attached to the support member at a position spaced apart from the first rotation axis.

6. The mobile robot according to claim 3, wherein the biasing member has an elastic body, one end of which is attached to one of the support members among the plurality of units at a position spaced apart from the first rotation axis, and the other end of which is attached to another of the support members among the plurality of units at a position spaced apart from the first rotation axis.

7. The mobile robot according to claim 2, wherein each of the plurality of units has a supporter attached to the support member so as to be rotatable about a second rotation axis parallel to the first rotation axis, and the member is located between the body and the supporter.

8. The mobile robot according to claim 7, wherein the supporter is provided with a notch, and the supporter is configured to rotate around the second rotation axis relative to the support member, thereby causing the support member to enter the notch.

9. The mobile robot according to claim 2, wherein the body has an outer surface facing the plurality of units and the member, the member has a first surface supported by the outer surface and a second surface located opposite to the first surface, and when the member is maximally expanded, the second surface is inclined with respect to the outer surface such that the distance between the second surface and the outer surface decreases toward the first mounting portion, and supports the support member.

10. A mobile robot according to claim 1, further comprising two wall bodies, the body having outer surfaces facing the plurality of units and the member, the two wall bodies being spaced apart from each other in a direction along the outer surfaces, and the member being located between the two wall bodies and having its expansion in that direction restricted by contact with at least one of the two wall bodies.

11. The mobile robot according to claim 1, wherein the member surrounds the body.

12. The mobile robot according to claim 1, wherein the internal space has a plurality of rooms separated from each other.

13. The mobile robot according to claim 1, wherein the member comprises a plurality of individual members, each positioned between the body and one of the plurality of units.

14. The mobile robot according to claim 13, wherein the plurality of individual members include a first individual member and a second individual member located between the body and one of the plurality of units, and the first individual member is located between the body and the second individual member.

15. A robotic mobility system comprising: a mobile robot from any one of claims 1 to 14; a tube connected to the member; and a pressurizing device configured to supply gas to the internal space through the tube, wherein the mobile robot is configured to move relative to the pressurizing device.

16. The robotic movement system according to claim 15, further comprising a depressurizing device configured to draw gas from the internal space.

17. The robotic mobility system according to claim 16, wherein the decompression device is configured to draw gas from the internal space through the tube.

18. The robot movement system according to claim 16, wherein the depressurizing device has an ejector provided in the tube and configured to generate negative pressure by an airflow supplied from the pressurizing device.

19. The mobile robot according to claim 1, wherein the member retracts when the support member approaches the body.

20. A control method for a mobile robot comprising: a body; a plurality of units arranged around the body, each having a body; a traveling device configured to travel on a surface it is in contact with; and a support member that supports the traveling device and is movable relative to the body so as to change the distance between the body and the traveling device; and a member having a plurality of partitioned chambers inside, located between the body and the support member, and configured to expand when the plurality of chambers are filled with gas, the method comprising: using a pressurizing device spaced apart from the mobile robot, individually supplying gas to the plurality of chambers through a plurality of tubes connected to the plurality of chambers, thereby individually widening the distance between the body and the support member of the plurality of units by the expanding member, and changing the posture of the mobile robot with respect to the surface.

21. A control method for a mobile robot comprising: a body; a plurality of units arranged around the body, each having a body; a traveling device configured to travel on a contact surface; and a support member that supports the traveling device and is movable relative to the body so as to change the distance between the body and the traveling device; and a plurality of members, each positioned between the body and one of the support members of the plurality of units, and each configured to expand when filled with gas, wherein a pressurizing device spaced apart from the mobile robot individually sends gas into the interior of the plurality of members through a plurality of tubes connected to the plurality of members, thereby individually widening the distance between the body and the support member of the plurality of units by the expanding plurality of members, and changing the posture of the mobile robot with respect to the surface.

22. A control method for a mobile robot according to claim 20 or 21, further comprising driving the travel devices of the plurality of units individually by a control device.

23. A control method for a mobile robot comprising: a body; a plurality of units arranged around the body, each having a body; a traveling device configured to travel on a contact surface; and a support member that supports the traveling device and is movable relative to the body so as to change the distance between the body and the traveling device; and a member located between the body and the support member, having a plurality of partitioned chambers inside, and configured to expand when the plurality of chambers are filled with gas, the method comprising: sending gas to the plurality of chambers through a plurality of tubes connected to the plurality of chambers by a pressurizing device spaced away from the mobile robot, thereby bringing the traveling devices of the rear unit and the front unit spaced away from the rear unit in the direction of travel of the mobile robot into contact with the surface; stopping the transport of gas by the pressurizing device to one of the plurality of chambers located between the body and the support member of the front unit; and driving the traveling device by a control device to move the mobile robot in the direction of travel, causing the traveling device of the front unit to cross a gap provided on the surface. A method for controlling a mobile robot, comprising: sending gas by the pressurizing device to one of the plurality of rooms located between the body and the support member of the front unit, causing the traveling device of the front unit to come into contact with the surface; stopping the transport of gas by the pressurizing device to one of the plurality of rooms located between the body and the support member of the rear unit; driving the traveling device with the control device to move the mobile robot in the direction of travel, causing the traveling device of the rear unit to cross the gap; and sending gas by the pressurizing device to one of the plurality of rooms located between the body and the support member of the rear unit, causing the traveling device of the rear unit to come into contact with the surface.

24. A control method for a mobile robot comprising: a body; a plurality of units arranged around the body, each having a body; a traveling device configured to travel on a contact surface; and a support member that supports the traveling device and is movable relative to the body such that the distance between the body and the traveling device changes; and a plurality of members, each positioned between the body and one of the support members of the plurality of units, and each configured to expand when filled with gas, wherein the method involves: sending gas to the plurality of members through a plurality of tubes connected to the plurality of members by a pressurizing device spaced apart from the mobile robot, thereby bringing the traveling devices of a rear unit and a front unit spaced apart from the rear unit in the direction of travel of the mobile robot into contact with the surface; stopping the transport of gas by the pressurizing device to one of the plurality of members located between the body and the support member of the front unit; and driving the traveling device with a control device to move the mobile robot in the direction of travel, causing the traveling device of the front unit to cross a gap provided on the surface. A method for controlling a mobile robot, comprising: sending gas by the pressurizing device to one of the plurality of members located between the body and the support member of the front unit, causing the traveling device of the front unit to come into contact with the surface; stopping the transport of gas by the pressurizing device to one of the plurality of members located between the body and the support member of the rear unit; driving the traveling device with the control device to move the mobile robot in the direction of travel, causing the traveling device of the rear unit to cross the gap; and sending gas by the pressurizing device to one of the plurality of members located between the body and the support member of the rear unit, causing the traveling device of the rear unit to come into contact with the surface.

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