Wheels and moving parts

Abstract

The present invention provides a wheel and a mobile body that can be manufactured more easily than conventional methods. The wheel comprises a plurality of arc-shaped members, wherein adjacent arc-shaped members are arranged to be slidable with respect to each other; a plurality of arms connected to each of the plurality of arc-shaped members; a plurality of couplings that slidably connect two of the arms connected to two adjacent arc-shaped members; and an angle-changing mechanism attached to the arms that changes the angle between the two arms connected to the two adjacent arc-shaped members, around the coupling. In this way, since the angle-changing mechanism that changes the angle between the two arms connected to the two adjacent arc-shaped members is attached to the arms, the angle-changing mechanism is not provided inside the vehicle body. Therefore, the wheel and the vehicle body can be made independent, and the wheel itself can be easily manufactured separately from the vehicle body.

Description

Technical Field

[0001] The technology of the present disclosure relates to wheels and moving bodies.

Background Art

[0002] Patent Document 1 discloses a conventional technology of a deformable wheel that can be used as a circular wheel on flat ground and can be deformed when overcoming a step. The deformable wheel includes a Scott Russell mechanism that deforms the wheel attached to the axle. The Scott Russell mechanism includes an annular member through which the axle passes, and deforms the wheel by moving the annular member closer to or away from the wheel along the axle. In this conventional technology, in order to move the annular member closer to or away from the wheel along the axle, a first rack gear extending into the vehicle body is connected to the annular member of the right deformable wheel, and a second rack gear extending into the vehicle body is connected to the annular member of the left deformable wheel. A pinion gear meshing with the first rack gear and the second rack gear is provided in the vehicle body. When the pinion gear is rotated in the first rotation direction, each annular member approaches the wheel along the axle via the first rack gear and the second rack gear. When the pinion gear is rotated in the second rotation direction, each annular member is separated from the wheel along the axle via the first rack gear and the second rack gear.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology, since the first rack gear, the second rack gear, and the pinion gear are provided in the vehicle body, the deformable wheel itself cannot be easily manufactured by separating it from the vehicle body.

[0005] The present invention aims to provide a wheel and a mobile body that can be manufactured more easily than the conventional technology. [Means for solving the problem]

[0006] To achieve the above objective, a wheel according to a first aspect of the technology of this disclosure comprises a plurality of arc-shaped members, wherein adjacent arc-shaped members are arranged to be slidable from one another, and a plurality of arms connected to each of the plurality of arc-shaped members. The wheel comprises a plurality of couplings that slidably connect two of the arms connected to two adjacent arc-shaped members. The wheel comprises an angle-changing mechanism attached to the arms that changes the angle between the two arms connected to two adjacent arc-shaped members, with respect to the coupling.

[0007] In the second embodiment, the parallel link mechanism is configured by the plurality of arms and the plurality of connecting parts in the first embodiment.

[0008] A third aspect is the first aspect, wherein the angle-changing mechanism includes a fixed portion fixed to one of the two arms. The angle-changing mechanism includes a rotating portion fixed to the other of the two arms, which rotates the fixed portion so that the angle formed between the one arm and the other arm changes around the joint.

[0009] The mobile body of the fourth embodiment comprises the plurality of wheels described in the first embodiment, with at least one of them being the front and rear wheels in the direction of travel.

[0010] The fifth embodiment of the moving body further comprises a control unit that controls the angle change mechanism so that the overall orientation of the plurality of arc-shaped members changes between a first state and a second state, as in the fourth embodiment. The first state is a state in which the outer circumference of the plurality of arc-shaped members forms a circle. The second state is a state in which the length of the plurality of arc-shaped members as a whole in a predetermined direction along the plane containing the circle is longer than the diameter of the circle.

[0011] In the sixth embodiment of the moving body, in the fifth embodiment, the control unit controls the angle change mechanism so that the overall orientation of the plurality of arc-shaped members is in the second state when the moving body is located in front of the obstacle. The control unit controls the angle change mechanism so that the overall orientation of the plurality of arc-shaped members is in the first state when the moving body is not located in front of the obstacle. [Effects of the Invention]

[0012] In a first aspect of the technology of this disclosure, an angle-changing mechanism that changes the angle between two arms connected to two adjacent arc-shaped members is attached to the arm, so that no angle-changing mechanism is provided inside the vehicle body. Therefore, the wheel and the vehicle body can be made independent, and the wheel itself can be easily manufactured separately from the vehicle body.

[0013] In the second embodiment, by configuring a parallel link mechanism with multiple arms and connecting parts, the motion of the arc-shaped member is stabilized, enabling smooth deformation. This improves the accuracy of attitude control during wheel deformation, and enhances durability and reliability.

[0014] In the third embodiment, since the angle change mechanism is composed of a fixed part and a rotating part, the angle of the arm can be adjusted smoothly and precisely.

[0015] In the fourth embodiment, by applying the wheels of the first embodiment to a moving body, it becomes possible to move while dealing with obstacles by utilizing the unique deformation mechanism of the wheels.

[0016] In the fifth embodiment, the vehicle can move stably in a circular shape during normal operation, and can overcome obstacles by extending its length. This improves the mobility of the vehicle.

[0017] In the sixth embodiment, the control unit automatically changes the shape of the wheels, thereby maintaining an optimal wheel shape according to the driving environment of the moving object. In particular, by changing to an appropriate shape in front of an obstacle, efficient obstacle overcoming becomes possible, improving the smoothness and stability of movement.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a side view of an example of the mobile body 10 of the present embodiment. [Figure 2] FIG. 2 is a perspective view of an example of the mobile body 10 of the present embodiment. [Figure 3] FIG. 3 is a diagram showing an example of the configuration of the wheel 14W as viewed from the main body 12 of the mobile body 10. [Figure 4] FIG. 4 is a perspective view showing an example of the angle change mechanism 26A. [Figure 5] FIG. 5 is a diagram showing an example of the configuration of the angle change mechanism 26A as viewed from the arm side. [Figure 6] FIG. 6 is a block diagram showing an example of the electrical system of the mobile body 10. [Figure 7] FIG. 7 is a diagram showing an example of the processing of each functional part of the processor 52. [Figure 8] FIG. 8 is a flowchart showing an example of the traveling processing program 56P. [Figure 9] [[ID=३१]]FIG. 9 is a diagram showing an example of a state where the mobile body 10 is located a predetermined distance L in front of the staircase [Figure 9] . [Figure 10] FIG. 10 is a diagram showing an example of a state where the wheel 14W is deformed when the mobile body 10 is located a predetermined distance L in front of the staircase 90. [Figure 11] FIG. 11 is a diagram showing an example of a state where the mobile body 10 starts climbing the staircase 90 with the wheel 14W deformed. [Figure 12] FIG. 12 is a diagram showing an example of a state where the mobile body 10 is climbing the staircase 90 with the wheel 14W deformed. [Figure 13] FIG. 1३ is a diagram showing an example of a state where the mobile body 10 has finished climbing the staircase 90 with the wheel 14W deformed. [Figure 14] FIG. 14 is a diagram showing an example of a state where the wheel 14W in the first modification deforms its shape and travels through the gap 90H. [Figure 15]Figure 15 shows an example of the configuration of the wheel 114W in a second modified example. [Figure 16] Figure 16 shows an example of the configuration of wheel 124W in a third modified example. [Figure 17] Figure 17 is a perspective view of an example of the fourth modified example of the mobile body 10. [Modes for carrying out the invention]

[0019] [Embodiment] Embodiments of the technology of this disclosure will be described below with reference to the drawings.

[0020] (composition) The configuration of the mobile body 10 of this embodiment will now be described. Figure 1 is a side view of an example of the mobile body 10 of this embodiment. Figure 2 is a perspective view of an example of the mobile body 10 of this embodiment. As shown in Figures 1 and 2, the mobile body 10 comprises a main body 12, a distance sensor 38 positioned on the front side of the main body 12 in the direction of travel, and a plurality of wheels, for example, four wheels 14W, as at least one pair of wheels each on the front and rear sides in the direction of travel. The distance sensor 38 measures the distance between the main body 12 and an obstacle located on the front side of the main body 12 in the direction of travel, for example, stairs 90 (see also Figure 9).

[0021] The distance sensor 38 may be an ultrasonic sensor that emits ultrasonic waves and calculates the distance by measuring the time it takes for the waves to reflect back from the object, or a laser sensor (LIDAR (Light Detection and Ranging)) that emits laser light and calculates the distance by measuring the time of reflection (TOF) and phase difference. Each wheel 14W is attached to the axle 15 (see also Figure 6).

[0022] The mobile unit 10 is equipped with magnetic sensors 35M corresponding to each wheel 14W. Each magnetic sensor 35M detects the magnitude of the magnetic force from a magnet 26M provided on an angle change mechanism 26A (see also Figure 3) provided on each wheel 14W, which will be described later. Two magnetic sensors 35M corresponding to each of the front pair of wheels 14W are positioned on the upper surface of the main unit 12, vertically above the line passing through the axle 15 of the front pair of wheels 14W. Two magnetic sensors 35M corresponding to each of the rear pair of wheels 14W are positioned on the upper surface of the main unit 12, vertically above the line passing through the axle 15 of the rear pair of wheels 14W.

[0023] Since the four wheels 14W have the same configuration, we will explain one wheel 14W and omit the explanations for the other three wheels 14W.

[0024] Figure 3 shows an example of the configuration of the wheel 14W as seen from the main body 12 of the mobile body 10. As shown in Figure 3, the wheel 14W comprises a plurality of arc-shaped members 20S1 to 20S4, where adjacent arc-shaped members 20S1 to 20S4 are arranged to slide relative to each other. Arc-shaped member 20S1 and arc-shaped member 20S2 are adjacent, arc-shaped member 20S2 and arc-shaped member 20S3 are adjacent, arc-shaped member 20S3 and arc-shaped member 20S4 are adjacent, and arc-shaped member 20S4 and arc-shaped member 20S1 are adjacent. Arc-shaped member 20S1 and arc-shaped member 20S2 are not directly connected. The same applies to other adjacent arc-shaped members. Alternatively, through holes (not shown) may be provided in the arc-shaped member 20S1 and the arc-shaped member 20S2, and shafts (not shown) may be inserted into each through hole, thereby directly connecting the arc-shaped member 20S1 and the arc-shaped member 20S2 so that they can slide against each other. Other adjacent arc-shaped members may be treated similarly.

[0025] The wheel 14W comprises multiple arms 24A, 22A, 24B, and 22B connected to each of the multiple arc-shaped members 20S1 to 20S4. When the shape of the wheel 14W is arc-shaped (see Figure 3), arms 24A and 24B are parallel, and arms 22A and 22B are parallel, while arms 24A and 24B are perpendicular to arms 22A and 22B. In this case, the state of each wheel 14W is the first state in which the outer circumference of the multiple arc-shaped members 20S1 to 20S4 forms a circle.

[0026] In this embodiment, arc-shaped members 20S1 and 20S3 are further away from the main body 12 than arc-shaped members 20S2 and 20S4 (towards the back of the page in Figure 3). One end and the other end of each arm 22A and arm 22B are connected to arc-shaped members 20S1 and 20S3. One end and the other end of each arm 24A and arm 24B are connected to arc-shaped members 20S2 and 20S4. Arms 22A and 22B are further away from the main body 12 than arms 24A and 24B (towards the back of the page in Figure 3).

[0027] The wheel 14W is provided with multiple coupling parts 25 that slidably connect two arms, which are connected to two adjacent arc-shaped members. The multiple arms 24A, 22A, 24B, 22B and the multiple coupling parts 25 constitute a parallel link mechanism.

[0028] The wheel 14W is equipped with angle-changing mechanisms 26A and 26B that are attached to an arm and change the angle between two arms connected to two adjacent arc-shaped members, around the joint 25. Specifically, angle-changing mechanism 26A changes the angle between two arms 24A and arm 22A, connected to two adjacent arc-shaped members 20S1 and 20S2, around the joint. Angle-changing mechanism 26B changes the angle between two arms 22B and arm 24B, connected to two adjacent arc-shaped members 20S3 and 20S4, around the joint 25 (see also Figure 4). Note that either angle-changing mechanism 26A or 26B may be omitted.

[0029] Thus, an angle-changing mechanism 26A is positioned at the intersection of the two arms 24A and arm 22A that constitute the parallel link mechanism, and an angle-changing mechanism 26B is positioned at the intersection of the two arms 22B and arm 24B. Since the angle-changing mechanisms 26A and 26B are positioned symmetrically on the wheel 14W, the balance (center of gravity, rolling) can be improved compared to when either of the angle-changing mechanisms 26A or 26B is omitted. An angle-changing mechanism with a configuration similar to that of the angle-changing mechanism 26A may be further positioned at at least one of the intersections between the two arms 22A and arm 24B, and the intersection between the two arms 22B and arm 24A.

[0030] A magnet 26M is provided in either the angle change mechanism 26A or 26B, for example, in the angle change mechanism 26A.

[0031] The wheel 14W is equipped with a connecting arm 24AB that slidably connects arms 24A and 24B. An axle 15 is connected to the center of the connecting arm 24AB.

[0032] Since the angle change mechanisms 26A and 26B have the same configuration, the configuration of angle change mechanism 26A will be described, and the configuration of angle change mechanism 26B will be omitted. Figure 4 is a perspective view showing an example of angle change mechanism 26A. Figure 5 is a diagram showing an example of the configuration of angle change mechanism 26A as seen from the arm side. As shown in Figures 4 and 5, angle change mechanism 26A includes a fixed part 28A12 fixed to arm 24A. Angle change mechanism 26A includes a rotating part 26A1 that rotates arm 24A relative to arm 22A. Specifically, the rotating part 26A1 rotates the fixed part 28A12 around the coupling part 25 so that the angle between arm 22A and arm 24A changes. The rotating part 26A1 is fixed to bracket 27A. Bracket 27A is fixed to arm 22A. Therefore, the rotating part 26A1 is also fixed to arm 22A. The rotating part 26A1 is, for example, a servo motor. Through holes 22AH and 24AH are provided in arms 22A and 24A, and the connecting portion 25 is inserted into the through holes 22AH and 24AH, thereby slidably connecting arms 22A and 24A.

[0033] As shown in Figure 5, the fixed part 28A12 is attached to the output shaft 26A1x of the servo motor (rotating part 26A1) and includes a pair of members 28A1 and 28A2 that transmit the rotational motion of the servo motor (rotating part 26A1) to the arm 24A. The pair of members 28A1 and 28A2 are, for example, servo horns. When member 28A1 rotates downward by a predetermined angle (for example, 46°) as shown in Figure 5, and member 28A2 rotates upward by a predetermined angle (for example, 46°), the angle between arm 22A and arm 24A decreases (for example, 44°). When member 28A1 rotates upward by a predetermined angle as shown in Figure 5, and member 28A2 rotates downward by a predetermined angle, the angle between arm 22A and arm 24A increases (for example, 136°).

[0034] When the angle between arm 22A and arm 24A changes from 90° to 44°, the shape of the wheel 14W changes from the first state to the first aspect of the second state. As described above, the first state is a state in which the outer circumference of the multiple arc-shaped members 20S1 to 20S4 forms a circle. The first aspect of the second state is a state in which the length of the entire set of arc-shaped members 20S1 to 20S4 along the plane containing the circle in a predetermined direction F (see Figure 10) becomes longer than the diameter of the circle. Specifically, the predetermined direction F is the direction of the line passing through the angle change mechanisms 26A and 26B.

[0035] When the angle between arms 22A changes from 90° to 136°, the shape of the wheel 14W changes from the first state to a second aspect of the second state. The second aspect of the second state is a state in which the length of the predetermined direction G along the plane containing the circle of the multiple arc-shaped members 20S1 to 20S4 is longer than the diameter of the circle. The predetermined direction G is specifically a direction perpendicular to the predetermined direction F.

[0036] In the second state, each of the multiple arc-shaped members 20S1 to 20S4 is connected to an adjacent arc-shaped member in a mountain fold or valley fold configuration.

[0037] Specifically, in the first embodiment of the second state, as shown in Figure 10, the connection between arc-shaped member 20S1 and arc-shaped member 20S2 is a mountain fold, and the connection between arc-shaped member 20S2 and arc-shaped member 20S3 is a valley fold. The connection between arc-shaped member 20S3 and arc-shaped member 20S4 is a mountain fold, and the connection between arc-shaped member 20S4 and arc-shaped member 20S1 is a valley fold. As a result, the length of the entire set of arc-shaped members 20S1 to 20S4 in a predetermined direction F (direction of the line passing through the angle change mechanisms 26A and 26B) along the plane containing the circle becomes longer than the diameter of the circle.

[0038] In the second correspondence of the second state, unlike the example shown in Figure 10, the connection between arc-shaped member 20S1 and arc-shaped member 20S2 is a valley fold, and the connection between arc-shaped member 20S2 and arc-shaped member 20S3 is a mountain fold. The connection between arc-shaped member 20S3 and arc-shaped member 20S4 is a valley fold, and the connection between arc-shaped member 20S4 and arc-shaped member 20S1 is a mountain fold. The total length of the multiple arc-shaped members 20S1 to 20S4 along the plane containing the circle in a predetermined direction G (a direction perpendicular to the predetermined direction F) becomes longer than the diameter of the circle.

[0039] Thus, the second state has a first aspect and a second aspect. In the first aspect, the angle-changing mechanisms 26A and 26B move closer together, and in the second aspect, the angle-changing mechanisms 26A and 26B move further apart.

[0040] Furthermore, the angle-changing mechanisms 26A and 26B are not limited to the configuration equipped with servo motors as described above; for example, they may also be configured with electromagnets. Specifically, by controlling the direction of the current flowing through each electromagnet, the interaction between the electromagnets (attraction or repulsion) can be used to move the angle-changing mechanisms 26A and 26B closer together or further apart.

[0041] Figure 6 is a block diagram showing an example of the electrical system of the mobile body 10. As shown in Figure 6, the electrical system of the mobile body 10 includes angle change mechanisms 26A and 26B provided on each wheel 14W, a travel motor 34 with a drive shaft connected to the axle 15 of each wheel 14W, and a rotary encoder 36 attached to the travel motor 34.

[0042] The electrical system of the mobile body 10 includes a magnetic sensor 35M that detects the magnitude of the magnetic force from a magnet 26M provided on the angle-changing mechanism 26A. The position of the angle-changing mechanism 26A can be estimated from the position of the magnetic sensor 35M and the magnitude of the magnetic force from the magnet 26M detected by the magnetic sensor 35M. Alternatively, instead of the magnet 26M and the magnetic sensor 35M, firstly, the main body 12 may be equipped with a camera that photographs the wheel 14W, and the position of the angle-changing mechanism 26A may be estimated based on the image obtained from the camera photographing the wheel 14W. Secondly, an acceleration sensor or an inertial measurement unit (IMU) may be fixed to the wheel 14W. The direction of gravitational acceleration is detected by the acceleration sensor or IMU to calculate the angle of the wheel, and the position of the angle-changing mechanism 26A is estimated from the angle of the wheel. Furthermore, the calculation of the wheel angle using an accelerometer or IMU works as follows: for example, if the -y direction of the accelerometer is fixed to the wheel vertically downwards when the wheel angle is 0 degrees, then when the wheel rotates 90 degrees, the gravitational acceleration will be detected as +x or -x (depending on the direction of rotation), and when it rotates 180 degrees, the gravitational acceleration will be detected as +y.

[0043] The electrical system of the mobile unit 10 includes a distance sensor 38, a start switch (SW) 40SW1, a stop switch (SW) 40SW2, and a control device 32. Each travel motor 34 is fixed to the main body 12. The control device 32 is an example of a "control unit" in the technology of this disclosure.

[0044] The control device 32 includes an external interface (I / F) 44 and a computer 42. The computer 42 includes a processor 52, RAM (Random Access Memory) 54, and NVM (Non-volatile memory) 56. The processor 52, RAM 54, and NVM 56 are interconnected via a bus 58 so that they can communicate with each other.

[0045] The processor 52 is a processing unit that includes a DSP (Digital Signal Processor), a CPU (Central Processing Unit), and a GPU (Graphics Processing Unit). The DSP and GPU operate under the control of the CPU and are responsible for executing the driving process. Here, a processing unit including a DSP, CPU, and GPU is given as an example of the processor 54, but this is only an example, and the processor 52 may be one or more CPUs and DSPs with integrated GPU functionality, or one or more CPUs and DSPs without integrated GPU functionality, or it may be equipped with a TPU (Tensor Processing Unit).

[0046] NVM56 is a non-volatile memory device that stores various programs and parameters. An example of NVM56 is flash memory (e.g., EEPROM (Electrically Erasable and Programmable Read Only Memory)). The NVM56 stores the driving process program 56P.

[0047] RAM54 is memory that temporarily stores information and is used as work memory by the processor52. Examples of RAM54 include DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory).

[0048] The functional unit of the processor 52 includes a driving processing unit 52A, an input unit 52B, a drive unit 52C, and a determination unit 52D. The processor 52 reads a driving processing program 56P from the NVM 56 and performs driving processing by executing the read driving processing program 56P on the RAM 54. Driving processing is realized when the processor 52 operates as the driving processing unit 52A, input unit 52B, drive unit 52C, and determination unit 52D according to the driving processing program 56P executed on the RAM 54.

[0049] Figure 7 shows an example of the processing of each functional unit of the processor 52. When the start switch 40SW1 is operated, the driving processing unit 52A controls the driving motors 34 connected to the axles 15 of each wheel 14W to start driving. The data acquisition unit 52B acquires measured values ​​from the distance sensor 38, and the judgment unit 52D determines, based on the acquired measured values, whether or not the vehicle is a predetermined distance L from the stairs 90.

[0050] If it is determined that the vehicle is a predetermined distance L away from the stairs 90, the travel processing unit 52A controls the travel motors 34 connected to the axles 15 of each wheel 14W to stop the vehicle from moving. The drive unit 52C determines the direction in which to lengthen the overall length of the multiple arc-shaped members 20S1 to 20S4 based on the detected value obtained by the magnetic sensor 35M, which detects the magnitude of the magnetic force from the magnet 26M provided on the angle change mechanism 26A, and controls the angle change mechanisms (servo motors) 26A and 26B so that the shape of each front wheel 14W deforms to lengthen in the determined direction.

[0051] The driving processing unit 52A controls the driving motors 34 connected to the axles 15 of each wheel 14W to start driving. The determination unit 52D determines whether each front wheel 14W has rotated by a predetermined angle based on signals from the rotary encoders 36 attached to the driving motors 34 connected to the axles 15 of each front wheel 14W. The drive unit 52C controls the angle change mechanisms 26A and 26B to return each front wheel 14W to its original shape.

[0052] (action) Next, the operation of this embodiment will be described. Figure 8 is a flowchart of an example of a driving process program 56P. The driving process and driving process method are executed when the processor 52 executes the driving process program 56P. The driving process program 56P starts when the start switch 40SW1 is operated.

[0053] In step 72, the running unit 52A controls the running motors 34 connected to the axles 15 of each wheel 14W to start running. At the start of running, the drive unit 52C controls the angle change mechanisms 26A and 26B so that each wheel 14W is in a first state where the outer circumference of the multiple arc-shaped members 20S1 to 20S4 forms a circle.

[0054] In step 74, the data acquisition unit 52B acquires the measurement value from the distance sensor 38.

[0055] In step 76, the determination unit 52D determines, based on the acquired measurement values, whether or not the vehicle is a predetermined distance L from the stairs 90, as shown in Figure 9. If it is determined that the vehicle is not a predetermined distance L from the stairs 90, the travel process returns to step 74. If it is determined that the vehicle is a predetermined distance L from the stairs 90, the travel process proceeds to step 78.

[0056] In step 78, the running unit 52A controls the running motors 34 connected to the axles 15 of each wheel 14W to stop the running.

[0057] In step 80, the drive unit 52C controls the angle change mechanisms 26A and 26B so that the shape of each front wheel 14W is deformed. Specifically, each front wheel 14W is set to the second state.

[0058] As described above, there are two directions in which the wheel 14W can deform: specifically, a first direction in which the angle between the arms 22A and 22A is 44° (first aspect of the second state), and a second direction in which the angle between the arms 22A and 22A is 136° (second state and second aspect).

[0059] In the first direction, as shown in Figure 10, the connection between arc-shaped member 20S1 and arc-shaped member 20S2 is a mountain fold, and the connection between arc-shaped member 20S2 and arc-shaped member 20S3 is a valley fold. The connection between arc-shaped member 20S3 and arc-shaped member 20S4 is a mountain fold, and the connection between arc-shaped member 20S4 and arc-shaped member 20S1 is a valley fold. The length of the entire set of arc-shaped members 20S1 to 20S4 in a predetermined direction F (direction of the line passing through the angle change mechanisms 26A and 26B) along the plane containing the circle is longer than the diameter of the circle.

[0060] In the second direction, unlike the example shown in Figure 10, the connection between arc-shaped member 20S1 and arc-shaped member 20S2 is a valley fold, and the connection between arc-shaped member 20S2 and arc-shaped member 20S3 is a mountain fold. The connection between arc-shaped member 20S3 and arc-shaped member 20S4 is a valley fold, and the connection between arc-shaped member 20S4 and arc-shaped member 20S1 is a mountain fold. The length of the entire set of arc-shaped members 20S1 to 20S4 in a predetermined direction G (a direction perpendicular to the predetermined direction F) along the plane containing the circle is longer than the diameter of the circle.

[0061] In step 80, the drive unit 52C controls the angle change mechanisms 26A and 26B such that the overall length of the multiple arc-shaped members 20S1 to 20S4 increases in the direction in which the angle with the height direction (i.e., the direction of gravity) of the stairs 90 is smaller, at a predetermined distance L before the stairs 90, among the predetermined directions F and G.

[0062] The direction in which a predetermined direction F is located at a predetermined distance L before the stairs 90 can be determined from the positions of the angle-changing mechanisms 26A and 26B. The positions of the angle-changing mechanisms 26A and 26B can be determined, for example, by detecting the magnitude of the magnetic force from the magnet 26M provided on the angle-changing mechanism 26A using a magnetic sensor 35M. Specifically, when each wheel 14W rotates in the first state so that the moving body 10 is moving, the angle-changing mechanism 26A moves along the circumference of a circle centered on the axle 15. As the angle-changing mechanism 26A moves away from the uppermost position on the vertically upper side of the axle 15 of the wheel 14W, the magnitude of the magnetic force detected by the magnetic sensor 35M gradually decreases. The magnitude of the magnetic force detected by the magnetic sensor 35M allows us to determine how far the angle-changing mechanism 26A is from the uppermost vertical position of the axle 15 of the wheel 14W, thereby determining the position of the angle-changing mechanism 26A. From the position of the angle-changing mechanism 26A, the position of the angle-changing mechanism 26B can be geometrically determined.

[0063] In step 82, the running unit 52A controls the running motors 34 connected to the axles 15 of each wheel 14W to start running.

[0064] Steps 78 and 82 may be omitted, and the shape of each front wheel 14W may be deformed while the vehicle is in motion.

[0065] In step 84, the determination unit 52D determines whether each front wheel 14W has rotated by a predetermined angle based on signals from rotary encoders 36 attached to the travel motors 34 connected to the axles 15 of each front wheel 14W. Specifically, the predetermined angle is the angle at which each front wheel 14W rotates as follows: That is, from the time travel begins in step 82, each front wheel 14W rotates and begins to climb the stairs 90 as shown in Figure 11. As shown in Figure 12, half the length of the deformed front wheel 14W in the predetermined direction F lies on the top surface of the stairs 90. Furthermore, it is the angle at which the remaining half of the length of the deformed front wheel 14W in the predetermined direction F lies above the top surface of the stairs 90. For example, it is 180° from the time travel begins in step 82.

[0066] In step 86, the drive unit 52C controls the angle change mechanisms 26A and 26B to return the shape of each front wheel 14W to its original state, as shown in Figure 13.

[0067] In step 88, the determination unit 52D determines whether or not the stop switch 40SW2 has been operated, thereby determining whether or not the vehicle has been instructed to stop.

[0068] If no instruction is given to stop the travel process, the travel process returns to step 74 and executes the above steps (steps 74 to 88). If there is another set of stairs, the process is carried out in the same manner as above.

[0069] If an instruction is given to stop the driving process, the driving process will terminate.

[0070] In the driving process described above, the shape of the front wheels 14W is changed to allow the vehicle to overcome the stairs 90, but the shape of the rear wheels 14W is controlled in the same way as the front wheels 14W. The processor 52 executes the processing for the rear wheels and the processing for the front wheels at predetermined time intervals, interrupting each other. In steps 74 and 76 of the processing for each rear wheel 14W, the processor determines whether the rear wheel 14W is a predetermined distance L before the stairs 90 based on the signal from the rotary encoder 36 provided on the driving motor 34 of each rear wheel 14W.

[0071] Alternatively, the system may include a processor for controlling the front wheels and a processor for controlling the rear wheels, allowing the front wheels 14W and the rear wheels 14W to be controlled independently.

[0072] (effect) As described above, in this embodiment, the wheel 14W has the angle change mechanism 26A attached to arms 24A and 22A, and the angle change mechanism 26B attached to arms 24B and 22B. Therefore, the angle change mechanisms 26A and 26B are not provided inside the main body 12. Thus, the wheel 14W and the main body 12 can be made independent, and the wheel 14W itself can be easily manufactured separately from the main body 12. Furthermore, because the wheel 14W and the main body 12 can be made independent in this way, it is possible to easily attach the wheel 14W to the main body 12.

[0073] As described above, the wheels 14W themselves can be easily manufactured by separating them from the main body 12. Furthermore, the control device 32 controls the angle change mechanisms 26A and 26B so that the shape of each front wheel 14W deforms in accordance with the stairs 90, so that the shape of the wheels 14W becomes elongated in a predetermined direction F / a predetermined direction G.Therefore, this embodiment can overcome obstacles such as stairs 90 without impairing the design freedom of the main body 12 of the mobile body 10.In other words, it can be attached to various mobile bodies without major modifications to the main body 12 of the mobile body 10.

[0074] When the wheel 14W is in the second state, the connection between each of the multiple arc-shaped members 20S1 to 20S4 and the adjacent arc-shaped member becomes either a mountain fold or a valley fold. This allows the height of the axle 15 to be raised compared to the first state, as shown in Figure 10, while shortening the distance between the point of application that hooks onto the stairs 90 and the stairs 90, making the height of the stairs 90 that the wheel 14W can overcome about half the diameter of the wheel 14W. In contrast, in conventional technology, the height of stairs that a wheel can overcome is about one-third the diameter of the wheel. There is a big difference between the height of stairs that a wheel can overcome being about one-third or one-half the diameter of the wheel. Specifically, it makes a difference whether the diameter of the wheel required to overcome stairs 90 of the same height is three times or two times. For example, if the height of the stairs is 20 cm, the former (1 / 3) requires a wheel with a diameter of 60 cm, while the latter (1 / 2) only requires a wheel with a diameter of 40 cm. Therefore, the wheel 14W in this embodiment can be made smaller than the wheel in the conventional method.

[0075] In this embodiment, the wheel 14W is configured with a parallel link mechanism consisting of multiple arms 24A, 22A, 24B, 22B and multiple connecting parts 25. This stabilizes the movement of the multiple arc-shaped members 20S1 to 20S4, enabling smooth deformation. As a result, the accuracy of attitude control during deformation of the wheel 14W is improved, and its durability and reliability are enhanced.

[0076] In the wheel 14W of this embodiment, the angle change mechanisms 26A and 26B are composed of a fixed part 28A12 and a rotating part 26A1, so that the angle between the arm 24A and the arm 22A can be adjusted smoothly and precisely.

[0077] In this embodiment, by applying the wheel 14W to the mobile body 10, it becomes possible to move while dealing with obstacles by utilizing the unique deformation mechanism of the wheel 14W.

[0078] In this embodiment, the mobile body 10 can move stably in a circular shape during normal travel, and can overcome obstacles by extending its length. This improves the mobility of the mobile body 10.

[0079] In this embodiment, the mobile body 10 can maintain an optimal wheel shape according to the driving environment of the mobile body 10 by automatically changing the shape of the wheels 14W using the control unit. In particular, by changing to an appropriate shape in front of an obstacle, efficient obstacle overcoming becomes possible, improving the smoothness and stability of movement. [Differentiation] Next, various modifications of the embodiments described above will be explained. Since the configuration and operation of each modification are substantially the same as those of the embodiments described above, the differences will be explained mainly.

[0080] (First variation) Figure 14 shows an example of how the wheel 14W in the first modified example deforms its shape to travel through the gap 90H.

[0081] In the above embodiment, climbing stairs 90 was used as an example (see Figures 9 to 13). In the first modified example, the mobile body 10 travels through the gap 90H by changing the shape of the wheels 14W, as shown in Figure 14.

[0082] The first modified mobile body 10 includes a camera (not shown) positioned on the front side of the main body 12 in the direction of travel. The camera captures images of the front side of the main body 12 in the direction of travel. The processor 52 detects the presence of a gap 90H by detecting an edge on the front side of the main body 12 in the direction of travel, based on the image captured by the camera.

[0083] In addition, a LiDAR (laser sensor) is placed on the front side of the moving body 10 in the direction of travel, and the gap 90H is detected by irradiating the front side with a laser and analyzing the reflected data to detect changes in the height of the ground. An ultrasonic sensor is installed on the front of the vehicle to measure the distance to the ground and detect the gap 90H. The gap 90H can be detected because the distance suddenly increases in the gap or groove.

[0084] If, in its first state, the wheel 14W cannot travel through a gap 90H with a length H longer than the diameter D1 of the wheel 14W, the shape of the wheel 14W is deformed (to the second state) before reaching the gap 90H. This makes the length D2 of the wheel 14W in a predetermined direction F (or predetermined direction G) longer than the length H of the gap 90H, allowing it to travel through the gap 90H.

[0085] Furthermore, if the length D2 of the wheel 14W in a predetermined direction F (or predetermined direction G) is shorter than the length H of the gap 90H, the moving body 10 will be driven while avoiding the gap 90H. (Second variation) Figure 15 shows an example of the configuration of the wheel 114W in a second modified example. In the above embodiment, the wheel 14W comprises four arc-shaped members 20S1 to 20S4, four arms 24A, 22A, 24B, and 22B, four connecting parts 25, and two angle-changing mechanisms 26A and 26B.

[0086] As shown in Figure 15, the wheel 114W in the second modified example comprises 10 arc-shaped members 120S1 to 120S10 and 5 arms 122A to 122E connected to each of the arc-shaped members 120S1 to 120S10. The wheel 114W includes a plurality (5) of coupling parts (not shown) that slidably connect two arms connected to two adjacent arc-shaped members. The wheel 114W includes angle-changing mechanisms 126A to 126E attached to the arms that change the angle between the two arms connected to two adjacent arc-shaped members, with respect to the coupling part. The coupling part is provided between the two arms and the angle-changing mechanisms 126A to 126E, as described above.

[0087] The state of the wheel 114W shown in Figure 15 is the first state in which the outer circumference of the 10 arc-shaped members 120S1 to 120S10 forms a circle.

[0088] The processor 52 controls the angle change mechanisms 126A to 126E so that, in front of the stairs or gap, the state of the wheel 114W is a second state in which the total length of the 10 arc-shaped members 120S1 to 120S10 along the plane containing the circle in a predetermined direction is longer than the diameter of the circle.

[0089] (Third variation) Figure 16 shows an example of the configuration of the wheel 124W in a third modified example. In the above embodiment, the wheel 14W comprises four arc-shaped members 20S1 to 20S4, four arms 24A, 22A, 24B, and 22B, four connecting parts 25, and two angle-changing mechanisms 26A and 26B.

[0090] As shown in Figure 16, the wheel 124W in the third modified example comprises twelve arc-shaped members 220S1 to 220S12 and six arms 222A to 222F connected to each of the arc-shaped members 220S1 to 220S12. The wheel 124W includes a plurality of coupling parts (not shown) that slidably connect two arms connected to two adjacent arc-shaped members. The wheel 124W includes six angle-changing mechanisms 226A to 226F attached to the arms that change the angle between two arms connected to two adjacent arc-shaped members, around the coupling part. The coupling parts are provided between the two arms and the angle-changing mechanisms 226A to 226F, as described above.

[0091] The state of the wheel 114W shown in Figure 16 is the first state in which the outer circumference of the 12 arc-shaped members 220S1 to 220S12 forms a circle.

[0092] The processor 52 controls the angle change mechanisms 226A to 226F so that, in front of the stairs or gap, the state of the wheel 124W is a second state in which the total length of the 12 arc-shaped members 120S1 to 120S12 along the plane containing the circle in a predetermined direction is longer than the diameter of the circle.

[0093] In the second and third modifications, each angle-changing mechanism and the axle are connected by a telescopic rod (telescopic arm) (for example, an extension rod). This allows the distance between each angle-changing mechanism and the axle to change as the state of wheels 114W and 124W changes between the first and second states, and this can be accommodated by changing the length of the telescopic rod.

[0094] (Fourth variation) Figure 17 is a perspective view of an example of a fourth modified example of the moving body 10. In the above embodiment, each of the multiple arc-shaped members 20S1 to 20S4 is made of one member. The technology of this disclosure is not limited thereto. For example, as shown in Figure 17, each of the multiple arc-shaped members 20S1 to 20S4 may be made of two members (double configuration). For example, the wheel 14W comprises two arc-shaped members 20S11, S12 and two arc-shaped members 20S41, S42. A gap 20S10 exists between the two arc-shaped members 20S11, S12, and a gap 20S40 exists between the two arc-shaped members 20S41, S42. For example, one end of arc-shaped member 20S42 is located in the gap 20S10 between two arc-shaped members 20S11 and S12, and one end of two arc-shaped members 20S11 is located in the gap 20S40 between two arc-shaped members 20S41 and S42. The same applies to the other arc-shaped members 20S2 and 20S3.

[0095] In this way, each arc-shaped member is constructed in a double layer, and one end of each arc-shaped member is positioned to overlap, which stabilizes the wheel 14 and stabilizes the movement of the mobile body 10.

[0096] Furthermore, in the above embodiment, the arc-shaped members 20S1 to 20S4 are not directly connected to each other. Therefore, when the wheel 14W deforms, the deformation may become unstable. In this regard, in the fourth modified example, as described above, the deformation can be stabilized by sandwiching the arc-shaped members in a double layer.

[0097] Each arc-shaped member may be constructed in three or more layers, and positioned so that one end of each arc-shaped member overlaps.

[0098] (Other variations) Wheel 14W is constructed by dividing a circle into 4 parts, wheel 114W by dividing a circle into 5 parts, and wheel 124W by dividing a circle into 6 parts, but it is also possible to divide it into 7 or more parts. [Explanation of symbols]

[0099] 10 Mobile Units 12 Main unit 14W wheels 15 axles 20S1 Arc-shaped member 20S2 Arc-shaped member 20S3 Arc-shaped member 20S4 Arc-shaped member 22A Arm 22AH through hole 22B Arm 24A arm 24AB Connecting Arm 24AH through hole 24B Arm 25 Joint 26A Angle change mechanism 26A1 Rotating part 26A1x Output shaft 26B Angle change mechanism 26M Magnet 27A Bracket 27B Bracket 28A1 component 28A12 Fixed part 28A2 component 32 Control device 34. Driving motor 35M Magnetic Sensor 36 Rotary Encoders 38 Distance Sensor 40SW1 Start Switch 40SW2 Stop Switch 42 Computers 44 External Interface (I / F) 52 processors 52A Travel Processing Unit 52B Input section 52C Drive Unit 52D Judgment Department 54 processors 56P Driving Processing Program 56 NVM 58 Bus 90 stairs 90H gap 114W wheels 120S1 Arc-shaped member 120S10 Arc-shaped member 120S2 Arc-shaped member 120S3 Arc-shaped member 120S4 Arc-shaped member 120S5 Arc-shaped member 120S6 Arc-shaped member 120S7 Arc-shaped member 120S8 Arc-shaped member 120S9 Arc-shaped member 122A Arm 122B Arm 122C Arm 122D Arm 122E Arm 124W wheels 126A Angle change mechanism 126B Angle change mechanism 126C Angle change mechanism 126D Angle change mechanism 126E Angle change mechanism 220S1 Arc-shaped member 220S10 Arc-shaped member 220S11 Arc-shaped member 220S12 Arc-shaped member 220S2 Arc-shaped member 220S3 Arc-shaped member 220S4 Arc-shaped member 220S5 Arc-shaped member 220S6 Arc-shaped member 220S7 Arc-shaped member 220S8 Arc-shaped member 220S9 Arc-shaped member 222A Arm 222B Arm 222C arm 222D Arm 222E Arm 222F Arm 226A Angle change mechanism 226B Angle change mechanism 226C Angle change mechanism 226D Angle change mechanism 226E Angle change mechanism 226F Angle change mechanism D1 diameter F predetermined direction G predetermined direction L specified distance

Claims

1. A plurality of arc-shaped members, wherein adjacent arc-shaped members are arranged to be slidable from one another, Multiple arms connected to each of the aforementioned multiple arc-shaped members, Multiple connecting parts that allow two arms connected to two adjacent arc-shaped members to slide relative to each other, An angle-changing mechanism that changes the angle between two arms, which are attached to the arms and connected to two adjacent arc-shaped members, around the joint; Equipped with, The plurality of arms and the plurality of connecting parts constitute a parallel link mechanism. wheel.

2. The angle change mechanism is, A fixing part fixed to one of the two aforementioned arms, A rotating part is fixed to the other of the two arms, and rotates the fixed part so that the angle between the two arms changes around the joint, Equipped with, The wheel according to claim 1.

3. A mobile body comprising a plurality of wheels, at least one of which is the front and rear wheels in the direction of travel, Each of the aforementioned wheels is A plurality of arc-shaped members, wherein adjacent arc-shaped members are arranged to be slidable from one another, Multiple arms connected to each of the aforementioned multiple arc-shaped members, Multiple connecting parts that allow two arms connected to two adjacent arc-shaped members to slide relative to each other, An angle-changing mechanism that changes the angle between two arms, which are attached to the arms and connected to two adjacent arc-shaped members, around the joint; Equipped with, The aforementioned moving body is The system includes a control unit that controls the angle change mechanism so that the overall orientation of the plurality of arc-shaped members changes between a first state in which the outer circumference of the plurality of arc-shaped members forms a circle, and a second state in which the length of the plurality of arc-shaped members as a whole in a predetermined direction along the plane including the circle becomes longer than the diameter of the circle. A mobile object.

4. The control unit controls the angle change mechanism such that when the moving body is positioned in front of the obstacle, the overall orientation of the plurality of arc-shaped members is in the second state, and when the moving body is not positioned in front of the obstacle, the overall orientation of the plurality of arc-shaped members is in the first state. The mobile body according to claim 3.

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