Parallel link mechanism, transport device, and working robot

Abstract

To provide a parallel link mechanism which rotates a rotating body by operation of a movable link and enables increase of a rotation width of the rotating body without increasing the size of the parallel link mechanism.SOLUTION: A parallel link mechanism (100a) includes: a base (1) which includes guide members (124); movable bodies (2) which can move along the guide member; a fixed link (3) which has a base end part fixed to the base and extends in a direction away from the base; a rotating body (4) which is connected to a tip of the fixed link and can rotate around the tip; and movable links (5) each of which has a base end part connected to the movable body, has a tip connected to the rotating body, and rotates the rotating body in response to movement of the movable bodies. The guide member inclines so as to get closer to the rotating body as going away from a center part of a base body (11).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a parallel link mechanism, a transport device, and a working robot. [Background technology]

[0002] Conventionally, a platform stabilizing device as described in Patent Document 1 is known. This platform stabilizing device includes a base, a platform, a central support, a first lifting support, and a second lifting support. The central support maintains a constant distance between the base and the center of the bottom surface of the platform, and supports the platform so that the angle of the platform relative to the base can be freely adjusted. The first lifting support is disposed at an appropriate distance from the central support in front or rear of the traveling direction. The second lifting support is disposed at an appropriate distance from the central support in a direction perpendicular to the traveling direction. Each lifting support is controlled to rise and fall via a link mechanism. The link mechanism includes a drive arm that rotates by the rotary driving force of a servo motor, and a lifting shaft that is connected to the tip of the drive arm via a spherical bearing, and the tip of the lifting shaft is connected to the back surface of the platform via a spherical bearing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-93981 A Summary of the Invention [Problem to be solved by the invention]

[0004] Such a transport device that uses a parallel link mechanism to keep the platform horizontal is expected to be used in various places. However, in the above-mentioned conventional technology, the rotation range of the platform relative to the base is small, and the platform may not be kept horizontal on a steeply inclined slope. For this reason, the conventional technology is difficult to use in industries that involve work on steep slopes, such as forestry. On the other hand, it is possible to increase the rotation range of the platform relative to the base to a certain extent by enlarging the mechanism that tilts the platform. However, if the mechanism becomes larger, the transport device becomes larger overall, and new problems arise, such as, for example, the platform being too high, making it difficult to load and unload the load, or being too wide, making it difficult to pass through the road. In addition, the trade-off between the rotation range and the size of the mechanism has also been an issue in the field of work robots.

[0005] One aspect of the present invention has been made in consideration of the above-mentioned problems, and its object is to increase the rotational range of a rotating body in a parallel link mechanism in which a rotating body is rotated by the operation of a movable link, without increasing the size of the mechanism. [Means for solving the problem]

[0006] In order to solve the above problems, a parallel link mechanism according to one aspect of the present invention includes a base including a base body and a plurality of guide members each extending in a direction different from each other, away from a central portion of the base body toward a peripheral portion thereof; a plurality of movable bodies movable along each of the guide members; a fixed link having a base end fixed to a central portion of the base body and extending in a direction away from the base; a rotating body having a center connected to a tip end of the fixed link and rotatable around the tip end; a plurality of movable links each having a base end connected to the movable body and a tip end connected to a peripheral portion of the rotating body, the movable links rotating the rotating body in response to movement of the movable body; a sensor that detects an inclination of the rotating body with respect to a horizontal plane; and a processor that controls movement of the plurality of movable bodies based on a detection result of the sensor so that the inclination of the rotating body with respect to the horizontal plane becomes a desired magnitude, and at least any of the plurality of guide members is inclined so as to approach the rotating body the further away from the central portion of the base body the guide members are.

[0007] In order to solve the above problem, a transport device according to another aspect of the present invention is characterized in that it comprises a moving mechanism capable of moving on the ground, and the above-mentioned parallel link mechanism mounted on the moving mechanism.

[0008] In order to solve the above problems, a working robot according to another aspect of the present invention is characterized in that it includes the above-mentioned parallel link mechanism and a tool attached to an underside of a rotating body of the parallel link mechanism. Effect of the Invention

[0009] According to each aspect of the present invention, in a parallel link mechanism in which a rotating body is rotated by the operation of a movable link, it is possible to increase the rotational range of the rotating body without increasing the size of the mechanism. [Brief description of the drawings]

[0010] [Figure 1]1 is a perspective view showing an example of a conveying device according to a first embodiment of the present invention. [Diagram 2] FIG. 11 is a block diagram showing the electrical configuration of a parallel link mechanism provided in the device (a working robot according to a second embodiment of the present invention). [Diagram 3] 2 is a perspective view showing a base, a movable body, and a fixed link provided in the mechanism. FIG. [Figure 4] FIG. 4 is an enlarged perspective view of a part of FIG. [Diagram 5] 13 is a perspective view showing a tip portion of a fixed link provided in the mechanism. FIG. [Figure 6] 4 is a flowchart showing the flow of processing executed by a processor of the mechanism. [Figure 7] FIG. 13 is a side view showing the transport device moving on a slope. [Figure 8] FIG. 11 is a perspective view showing an example of a working robot according to a second embodiment of the present invention. [Figure 9] 13 is a flowchart showing the flow of processing executed by a processor of the parallel link mechanism provided in the robot. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] First Embodiment Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

[0012] <Construction of the transport device> The first embodiment of the present invention is a transport device 100. The transport device 100 transports a load. The load is not particularly limited, but the transport device 100 is suitable for transporting, for example, work tools of forestry workers, cut lumber, and the like. As shown in FIG. 1, the transport device 100 includes a parallel link mechanism 100a and a movement mechanism 100b.

[0013] [Moving mechanism] Each moving mechanism 100b is configured to be movable on the ground. The moving mechanism 100b according to this embodiment includes a power source 101 and a pair of left and right caterpillars 102. The power source 101 is an engine or a motor. The caterpillars 102 include a drive wheel (not shown) that rotates by the power from the power source 101, a guide wheel and a roller (not shown), and a cover plate 102a that surrounds them and moves with the rotation of the drive wheel. This allows each moving mechanism 100b to move even on a bad road such as a mountain forest (a road with obstacles such as stones, a steeply inclined slope). The moving mechanism 100b also includes an operation unit (not shown) that controls the power source 101. The moving mechanism 100b may be configured with the power source 101 and drive wheels without the cover plate 102a. The moving mechanism 100b may be a commercially available vehicle instead of a dedicated device.

[0014] [Parallel link mechanism configuration] The parallel link mechanism 100a is mounted on the moving mechanism 100b. The parallel link mechanism 100a includes a base 1, a plurality of moving bodies 2, a fixed link 3, a rotating body 4, and a plurality of movable links 5. As shown in Fig. 2, the parallel link mechanism 100a further includes a sensor 6, a power source 7, and a control board 8. The power source 7 and the control board 8 may be dedicated to the parallel link mechanism 100a, or may be shared with the moving mechanism 100b.

[0015] 〔base〕 3, the base 1 includes a base body 11 and a plurality of support members 12. The base 1 according to this embodiment includes four support members 12. Note that the number of support members 12 included in the base 1 may be three or less, or five or more.

[0016] (Base body) The base body 11 fixes the parallel link mechanism 100a to the moving mechanism 100b. The base body 11 according to this embodiment is composed of a plurality of rod-shaped fixed members 111. The plurality of fixed members 111 are arranged in the front-rear direction (the direction connecting the upper left and lower right in FIG. 3). Each fixed member 111 is arranged to extend in the left-right direction (the direction connecting the upper right and lower left in FIG. 3) and is hung between a pair of endless tracks 102. The left and right ends of each fixed member 111 are fixed to the pair of endless tracks 102. A support portion 111a that supports the base end portion of the fixed link 3 is provided at the center of the fixed member 111 that is arranged to pass through the center of the moving mechanism 100b when viewed in a plan view. The base body 11 may be composed of a single member. The support portion 111a may be provided on the moving mechanism 100b (for example, on the power source 101) instead of the fixed member 111.

[0017] (Support member) As shown in FIG. 4, the support member 12 according to this embodiment includes a first support pillar 121, a second support pillar 122, a beam portion 123, a guide member 124, and a rack 125.

[0018] ·Strut The first support 121 and the second support 122 support the girder 123. As shown in FIG. 3, the first support 121 is attached to both left and right ends of the fixed member 111 passing through the center of the moving mechanism 100b and to the center of each fixed member 111 passing through the front and rear ends of the moving mechanism 100b so as to extend upward. The height of the first support 121 is higher than that of the second support 122. The second support 122 is attached to the fixed member 111 between the support portion 111a of the fixed member 111 and each first support 121 so as to extend upward. The height of the second support 122 is lower than that of the first support 121. At least one of the first support 121 and the second support 122 may be attached to the moving mechanism 100b. In that case, the base 1 does not need to include the fixed member 111.

[0019] ·Girder part Each girder 123 is disposed so as to extend from the support portion 111a of the fixing member 111 to each first support 121 (front, rear, left and right), and is fixed to the upper end of the first support 121 and the upper end of the second support 122. As a result, each girder 123 extends from the center of the base body 11 in the front, rear, left and right directions. The first support 121 supporting the girder 123 on the side farther from the support portion 111a is higher than the second support 122 as described above. Therefore, each girder 123 is inclined so as to rise as it moves away from the center of the base body 11. The inclination angle of the girder 123 (the angle between the top surface of the girder 123 and the horizontal plane) is preferably within a range of 10 to 20°. The inclination angle according to this embodiment is 15°. The girder 123 may be supported by the first support 121 and the support portion 111a of the fixing member 111. In this case, the base 1 does not need to include the second support column 122 .

[0020] Guide parts The guide members 124 guide the moving body 2. Each guide member 124 is provided on the upper surface of each girder 123 so as to extend along the extension direction of the girder 123. As described above, each girder 123 extends in the front-rear and left-right directions. Therefore, the multiple guide members 124 according to this embodiment also extend forward, backward, and both left and right directions from the center (support portion 111a) of the base body 11. Also, as described above, each girder 123 is inclined. Therefore, all of the multiple guide members are inclined so as to rise as they move away from the center of the base body 11. The guide members 124 may be provided on the side or bottom surface of the girder 123.

[0021] ·rack Rack 125 is provided on the upper surface of each beam 123 so as to extend parallel to guide member 124. Note that rack 125 may be provided on the side or lower surface of beam 123. Furthermore, rack 125 may be provided on a surface of beam 123 different from the surface on which guide member 124 is provided.

[0022] (Bass and others) It is sufficient that the multiple beams 123 (multiple guide members 124, multiple racks 125) each extend in a direction different from each other, away from the peripheral edge of the base 1. For this reason, at least some of the multiple beams 123 may be arranged to extend from the center of the base body 11 in a (diagonal) direction other than the front, back, left, or right. It is also sufficient that at least any of the multiple beams 123 (multiple racks 125, multiple guide members 124) is inclined so as to rise as it moves away from the center of the base body 11. In other words, at least some of the multiple beams 123 do not need to be inclined.

[0023] [Mobile object] The multiple movable bodies 2 are movable along the respective guide members 124. As shown in Fig. 4, each movable body 2 includes a motor 21, a pinion 22, a reducer 23, and a connecting portion 24. In addition, as shown in Fig. 2, each movable body 2 further includes an encoder 25.

[0024] (Motor) The motor 21 rotates under the control of a processor 84 of the control board 8, which will be described later. The motor 21 according to this embodiment is a direct drive motor. Therefore, the moving body 2 (the base end of the movable link 5) can be moved at high speed and with high precision. In addition, the position of the moving body 2 can be fixed simply by stopping the supply of power. Note that the motor 21 may be a motor other than a direct drive motor.

[0025] (Pinion) 4, the pinion 22 meshes with the rack 125 and rotates in response to the rotation of the motor 21. When the pinion 22 rotates, the moving body 2 moves along the rack 125.

[0026] (reducer) The reducer 23 is provided between the motor 21 and the pinion 22. The reducer 23 improves the torque of the pinion 22 by interposing another gear between the gear directly attached to the rotating shaft of the motor 21 and the pinion 22.

[0027] (Connection part) The connecting part 24 is connected to the base end of the movable link 5. The connecting part 24 according to this embodiment is configured with a ball joint. The connecting part 24 according to this embodiment engages with the guide member 124 of the support member 12 and is slidable relative to the guide member 124. Note that a member other than the connecting part 24 in the movable body 2 may engage with the guide member 124.

[0028] (Encoder) The encoder 25 detects the rotation direction and rotation angle of the motor 21. Then, the encoder 25 outputs the detection result to the processor 84 of the control board 8.

[0029] [Permanent link] As shown in Fig. 3, the fixed link has a base end fixed to the center of the base body 11 and extends in a direction away from the base 1. The fixed link 3 according to this embodiment extends upward from the center of the base body 11. The fixed link 3 according to this embodiment has a link body 31 and a movable joint 32. The movable joint 32 is attached on the link body 31. In other words, the tip of the fixed link 3 serves as the movable joint 32.

[0030] As shown in FIG. 5, the movable joint 32 according to this embodiment has a first member 321, a second member 322, a first shaft portion 323, a third member 324, and a second shaft portion 325. The first member 321 is fixed to the tip of the link body 31. The second member 322 is pivotally supported by the first member 321 through the first shaft portion 323 extending in the front-rear direction. This allows the second member 322 to rotate relative to the first member 321 around the first shaft portion 323 as a rotation axis. The third member 324 is pivotally supported by the second member 322 through the second shaft portion 325 extending in a direction perpendicular to the extension direction of the first shaft portion 323 (in the left-right direction when the second member 322 is not rotating). This allows the third member 324 to rotate relative to the second member 322 around the second shaft portion 325 as a rotation axis. The movable joint 32 may have either the first shaft portion 323 or the second shaft portion 325. Moreover, the first shaft portion 323 of the movable joint 32 may extend in the left-right direction. Moreover, the movable joint 32 may have a shaft portion that extends in a direction different from the first shaft portion 323 and the second shaft portion 325.

[0031] [Rotating body] As shown in FIG. 1, the center of the rotating body 4 is connected to the tip (movable joint 32) of the fixed link 3. The rotating body 4 according to this embodiment is disposed above the base 1, and is connected to the tip of the fixed link 3 at the center of the lower surface. As described above, the tip of the fixed link 3 is the movable joint 32. Therefore, the rotating body 4 is rotatable around the tip of the fixed link 3. Specifically, the rotating body 4 is connected to the fixed link 3 so as to be rotatable around the first shaft 323 of the movable joint 32 as a rotation axis and to be rotatable around the second shaft 325 as a rotation axis. As a result, the rotating body 4 can tilt in all directions relative to the base 1, similar to the case where a ball joint is used. On the other hand, the movable joint 32 does not have an axis extending in the extension direction of the fixed link 3. Therefore, the rotation of the rotating body 4 around the shaft extending in the extension direction of the fixed link 3 as a rotation axis is restricted. In other words, the "rotation" action of the rotating body 4 does not include rotation about a straight line extending in the extension direction of the fixed link 3 as the rotation axis. The rotating body 4 according to this embodiment is a platform on whose upper surface a load can be placed. Hereinafter, the rotating body 4 according to this embodiment will be referred to as the platform 4. The platform 4 according to this embodiment is in the form of a rectangular plate in a plan view. The upper surface of the platform 4 is a loading surface 4a on which the load is placed.

[0032] [Movable link] As shown in FIG. 4, the base end of each of the movable links 5 is connected to the movable body 2 (connecting portion 24). As described above, each movable body 2 is disposed on a guide member 124 extending from the center of the base body 11 in the front-rear and left-right directions. For this reason, as shown in FIG. 1, the movable links 5 are disposed so as to surround the fixed link 3. The base end of the movable link 5 according to this embodiment is connected to the movable body 2 via a ball joint. In addition, the tip end of each of the movable links 5 is connected to the periphery of the platform 4. As shown in FIG. 1, each tip end of the movable link 5 according to this embodiment is connected to each of the front-rear and left-right ends of the platform 4. Specifically, the tip end of the movable link 5 whose base end is connected to the front (rear) movable body 2 is connected to the front end (rear end) of the platform 4, and the tip end of the movable link 5 whose base end is connected to the right (left) movable body 2 is connected to the right end (left end) of the platform 4.

[0033] As a result, the left, right, front and rear ends of the loading platform 4 are supported by the movable links 5 located below each end, so that even if a load is loaded on the end of the loading surface 4a, the load can be stably placed on the platform. Therefore, a person who is loading a load can load the load without worrying about where to place the load on the loading surface 4a. That is, the efficiency of the work of placing the load can be improved. In addition, since the peripheral portion of the loading platform 4 is supported as a whole, the loading surface 4a can be more reliably kept horizontal. The tip of the movable link 5 according to this embodiment is connected to the loading platform 4 via a ball joint. Note that the tip of the movable link 5 may be connected to a portion other than the front, rear, left and right ends of the loading platform 4 (for example, a portion closer to the center than the end, the four corners of the loading platform 4, etc.). The multiple movable links 5 connected to the moving body 2 and the loading platform 4 in this way rotate the loading platform 4 in response to the movement of the moving body 2.

[0034] [Sensor] The sensor 6 detects the inclination of the placement surface 4a of the loading platform 4 with respect to the horizontal plane. The sensor 6 according to the present embodiment is composed of a first angle sensor and a second angle sensor. The first angle sensor detects the inclination of the placement surface 4a in the front-rear direction (the angle α between the intersection line between the placement surface 4a and a plane extending in the front-rear direction and the vertical direction and the horizontal plane). The second angle sensor detects the inclination of the placement surface 4a in the left-right direction (the angle β between the intersection line between the placement surface 4a and a plane extending in the left-right direction and the vertical direction and the horizontal plane). Each angle sensor repeatedly detects the rotation angle at a predetermined period and repeatedly outputs the detection result to the processor 84. The sensor 6 may be composed of a gyro sensor that detects the angular velocity and angular acceleration, and a processor that calculates the angle between the horizontal plane and the placement surface 4a based on the detection result. The sensor 6 may also be composed of a plurality of position sensors that detect the height of each part of the loading platform 4, and a processor that calculates the angle between the horizontal plane and the placement surface 4a based on the detection results.

[0035] 〔power supply〕 The power supply 7 is composed of a battery (not shown) and a power supply circuit (not shown). The power supply circuit constantly supplies power from the battery to the sensor 6 and the control board 8. The power supply circuit also supplies the battery power to the motor 21 in response to an instruction from the processor 84.

[0036] [Control board] 2, the control board 8 includes an input / output interface 81, a primary memory 82, a secondary memory 83, and a processor 84. These are electrically connected via a bus 85.

[0037] (Input / Output Interface) The input / output interface 81 connects the encoder 25, the sensor 6, and the power supply circuit of the power supply 7 of the base 1 to the processor 84. The input / output interface 81 also connects the encoder 25, the sensor 6, and the secondary memory 83.

[0038] (Memory) The primary memory 82 stores at least a control program for operating the parallel link mechanism 100a. The secondary memory 83 is configured to store the detection results of the encoder 25 and the sensor 6.

[0039] (Processor) The processor 84 controls the movement of each of the multiple moving bodies 2 so that the inclination of the platform 4 with respect to the horizontal plane becomes a desired magnitude based on the detection result of the sensor 6. When the processor 84 according to this embodiment detects the inclination of 2a of the platform 4, it controls the movement of each of the multiple moving bodies 2 so that the inclination of the placement surface 4a is eliminated. Specifically, the processor 84 executes forward / rearward direction processing and left / right direction processing in parallel when a predetermined start condition is met. The start conditions include the power supply of the transporting device 100 (parallel link mechanism 100a) being turned on, a load being loaded onto the platform 4, the operation unit being operated, the transporting device 100 starting to move, etc.

[0040] As shown in FIG. 6, in the forward / rearward direction processing, the processor 84 repeatedly executes an acquisition step A1, a first judgment step A2, a calculation step A3, a control step A4, and a second judgment step A5. In the first acquisition step A1, the output value α (detected forward / rear tilt) of the first angle sensor is acquired. In the next first judgment step A2, it is judged whether the output value α is greater than a predetermined value (e.g., 0°). If it is judged that the output value α is equal to or less than the predetermined value (A2: NO), the process returns to the acquisition step A1. On the other hand, if it is judged that the output value α is greater than the predetermined value (A2: YES), the process proceeds to a calculation step A3. In the calculation step A3, the movement amount of the movable body 2 located in front of the fixed link 3 and the movement amount of the movable body 2 located behind the fixed link 3 are calculated so that the third member 324 of the movable joint 32 is tilted by −α with respect to the second member 322. In the next control step A4, the motor 21 of the moving body 2 located in front of the fixed link 3 is controlled so that the moving body 2 approaches or moves away from the center of the base body 11 by the calculated distance. Also, the motor 21 of the moving body 2 located behind the fixed link 3 is controlled so that the moving body 2 moves away or moves toward the center of the base body 11 until the placement surface 4a of the loading platform 4 becomes horizontal. In the next second judgment step A5, it is judged whether the transport device 100 (movement mechanism 100b) is moving. If it is judged that it is moving (A5: YES), the process returns to the acquisition step A1. On the other hand, if it is judged that it is not moving (A5: NO), the forward / rearward direction process is terminated.

[0041] In the left-right direction processing, the processor 84 repeatedly executes an acquisition step B1, a first judgment step B2, a calculation step B3, a control step B4, and a second judgment step B5. In the first acquisition step B1, the output value β (detected left-right tilt) of the second angle sensor is acquired. In the next first judgment step B2, it is judged whether the output value β is greater than a predetermined value (for example, 0°). If it is judged that the output value β is equal to or less than the predetermined value (B2: NO), the process returns to the acquisition step B1. On the other hand, if it is judged that the output value β is greater than the predetermined value (B2: YES), the process proceeds to a calculation step B3. In the calculation step B3, the movement amount of the movable body 2 located to the right of the fixed link 3 and the movement amount of the movable body 2 located to the left of the fixed link 3 are calculated so that the second member 322 of the movable joint 32 is tilted by -β with respect to the first member 321. In the next control step B4, each motor 21 of the moving body 2 located to the right of the fixed link 3 is controlled so that the moving body 2 approaches or moves away from the center of the base body 11 by the calculated distance. Also, the motor 21 of the moving body 2 located to the left of the fixed link 3 is controlled so that the moving body 2 moves away or moves toward the center of the base body 11 until the placement surface 4a of the loading platform 4 becomes horizontal. In the next second judgment step B5, it is judged whether the transport device 100 is moving. If it is judged to be moving (B5: YES), the process returns to the acquisition step B1. On the other hand, if it is judged not to be moving (B5: NO), the left-right direction process ends.

[0042] The processor 84 according to this embodiment rotates the motor 21 based on the detection result by the encoder 25. This eliminates the need for the processor 84 to grasp the rotation direction and rotation angle of the motor 21 by itself (for example, to measure the time that the motor 21 is energized). This simplifies the control performed by the processor 84.

[0043] <Operation of the transport device (parallel link mechanism)> In the transport device 100 configured as described above, a load is placed on the placement surface 4a of the platform 4. As described above, in the transport device 100 (parallel link mechanism 100a), the center of the platform 4 is supported by the fixed link 3. That is, the transport device 100 (parallel link mechanism 100a) has high overall rigidity. In addition, in the transport device 100 (parallel link mechanism 100a), the load of the load acting on the center of the platform 4 is borne by the fixed link 3 instead of the movable link 5. In addition, as described above, the reducer 23 is provided between the motor 21 and the pinion 22. Therefore, the moving body 2 is not moved by the load from the platform 4. Therefore, the transport device 100 can stably carry a heavy load.

[0044] When a user operates an operation unit (not shown), the power source 101 supplies power to the pair of caterpillar tracks 102, and the device starts moving in a direction corresponding to the operation performed on the operation unit at a speed corresponding to the operation. When the transport device 100 starts moving, the sensor 6 repeatedly detects the inclination of the placement surface 4a of the platform 4 with respect to the horizontal plane. When the transport device 100 runs over an obstacle or approaches a slope, the entire transport device 100 tilts. At this time, the platform 4 also tilts, and the sensor 6 detects the inclination of the placement surface 4a. Then, the processor 84 controls the motor 21 of the moving body 2 to move the moving body 2. When the moving body 2 moves, the movable link 5 moves, and the platform 4 rotates around the connection part with the fixed link 3. Then, the parallel link mechanism 100a can keep the placement surface 4a horizontal even if the moving mechanism 100b tilts according to the condition of the road surface R, as shown in FIG. 7. As described above, the four guide members 124 used for moving the movable body 2 extend forward, backward, and to both the left and right sides from the center of the base main body 11. Therefore, the placement surface 4a can be kept horizontal even if the base 1 is tilted in any direction.

[0045] Particularly in forests and the like, the inclination of a slope may change suddenly or frequently as the vehicle moves. However, as described above, the motor 21 is a direct drive motor. Therefore, even if the base 1 is suddenly tilted or the inclination of the base 1 changes frequently, the transport device 100 (parallel link mechanism 100a) can move the movable link 5 at high speed and with high precision and keep the placement surface 4a of the platform 4 horizontal. Also, as described above, a reducer 23 is provided between the motor 21 and the pinion 22. Therefore, the moving body 2 will not be moved even if a large load is momentarily applied from the platform 4 due to a change in inclination.

[0046] If there is no change in the inclination while the transport device 100 (parallel link mechanism 100a) is moving, the processor 84 stops the power supply to the motor 21. As described above, the motor 21 is a direct drive motor. Therefore, the transport device 100 (parallel link mechanism 100a) can fix the moving body 2 (the base end of the link) in place simply by stopping the power supply to the motor 21.

[0047] <Effects of the parallel link mechanism and transport device> As described above, the parallel link mechanism 100a described above is inclined so that the guide member 124 rises (closes to the platform 4) as it moves away from the center of the base body 11. Therefore, the horizontal width of the parallel link mechanism 100a is smaller than that of a conventional parallel link mechanism in which guide members of the same length are arranged horizontally. In other words, the parallel link mechanism 100a is compact. In other words, the parallel link mechanism 100a can make the length of the guide member 124 (the movable range of the moving body 2) longer than that of a conventional parallel link mechanism by increasing the horizontal width without exceeding that of a conventional parallel link mechanism. In addition, since the girder 123, the guide member 124, and the rack 125 are inclined, when the moving body 2 moves, the moving body 2 and the movable link 5 are also displaced in the extension direction of the fixed link 3. This displacement of the moving body 2 and the movable link 5 in the extension direction of the fixed link 3 is added to the operation of the movable link 5 when the platform 4 is rotated. As a result, the parallel link mechanism 100a can increase the rotation range of the platform 4 when the moving body 2 is moved a predetermined distance, compared to when a conventional parallel link mechanism in which the guide members are arranged horizontally moves the moving body the same distance. In this way, the parallel link mechanism 100a can increase the rotation range of the platform 4 without increasing the size of the mechanism.

[0048] Furthermore, by including the parallel link mechanism 100a, the transport device 100 can keep the placement surface 4a horizontal (transport the load stably) without increasing the size of the device on a slope that is inclined to an extent (for example, about 20°) that makes it difficult for a conventional transport device to keep the loading platform horizontal. Therefore, the transport device 100 can be used in industries that involve work on steep slopes, such as forestry. Furthermore, even if the rotation width of the rotating body 4 of the transport device 100 is large, the size (width, height) is smaller than that of a conventional transport device, so that the transport device 100 can load and unload loads and pass through roads as before.

[0049] Second Embodiment Next, a second embodiment of the present invention will be described in detail. For convenience of explanation, the same reference numerals will be used to designate members having the same functions as those described in the first embodiment, and the description thereof will not be repeated.

[0050] <Conveyor configuration> The second embodiment of the present invention is a working robot 200. As shown in Fig. 8, the working robot 200 includes a parallel link mechanism 200a and a tool 200b. The parallel link mechanism 200a according to this embodiment is disposed above the tool 200b.

[0051] [Parallel link mechanism configuration] The parallel link mechanism 200a according to this embodiment includes a base 1, a plurality of moving bodies 2, a fixed link 3, a rotating body 4, a plurality of movable links 5, a sensor 6, and a power supply 7 similar to those in the first embodiment, as well as a control board 8A as shown in Fig. 2. The parallel link mechanism 200a according to this embodiment also includes an input unit (not shown). Note that the power supply 7 according to this embodiment does not include a battery (it is composed of a power supply circuit and a power supply cable), and may be configured to receive power from a facility (such as a factory) in which the parallel link mechanism 200a is installed.

[0052] [Differences between the base, moving body, fixed link, rotating body, and movable link] As shown in FIG. 8, the parts of the parallel link mechanism 200a excluding the electrical configuration, i.e., the base 1, the plurality of moving bodies 2, the fixed link 3, the rotating body 4, and the plurality of movable links 5, are upside down compared to the parallel link mechanism 100a according to the first embodiment. That is, the fixed link 3 extends downward from the center of the base body 11. At least one of the plurality of guide members 124 is inclined so as to descend as it moves away from the center of the base body 11. The rotating body 4 is disposed below the base 1 and is connected to the tip of the fixed link 3 at the center of the upper surface. The rotating body 4 according to this embodiment can have a tool 200b attached to its lower surface. Note that FIG. 8 illustrates a plate-shaped rotating body 4 similar to that of the first embodiment, but the shape is not limited to the illustrated one as long as the tip of the movable link 5 can be connected and the tool 200b can be attached. Also, the moving body 2 according to this embodiment does not need to have a reducer 23.

[0053] [Input section] An operation instruction for the rotating body 4 is input to the input unit. The input unit may be a communication unit that receives the operation instruction from a teaching device or a remote control device, or may be a terminal that is connected to a teaching device or a remote control device. The teaching device is a device that generates an operation instruction based on an input (programming) by a user. The remote control device is a device that detects an operation or a user's movement by a user and generates an operation instruction according to the detection result. The input unit may be a drive that reads a medium on which an operation instruction is stored, or may be an operation unit that directly accepts an input operation of an operation instruction by a user.

[0054] 2, the control board 8A includes an input / output interface 81, a secondary memory 83, a processor 84, and a bus 85 similar to those of the control board 8 according to the first embodiment, as well as a primary memory 82A. The primary memory 82A stores a control program (different from that of the first embodiment) for operating the parallel link mechanism 200a.

[0055] When the processor 84 acquires an operation instruction for the rotating body 4, it controls the movement of each of the multiple movable bodies 2 so that the inclination of the rotating body 4 with respect to the horizontal plane becomes a magnitude according to the operation instruction. Specifically, the processor 84 executes the second forward / backward direction process and the second left / right direction process in parallel when a predetermined start condition is met. Examples of the start condition include the power supply of the work robot 200 (parallel link mechanism 200a) being turned on, the tool 200b starting to operate, the operation unit being operated, etc.

[0056] As shown in FIG. 9, in the second front-rear direction processing, the processor 84 repeatedly executes the second acquisition step C1, the third acquisition step C2, the third judgment step C3, the second calculation step C4, the second control step C5, and the fourth judgment step C6. In the first second acquisition step C1, a target value of the front-rear direction tilt of the mounting surface 4b (the angle θ between the intersection line of the plane extending in the front-rear direction and the vertical direction with the mounting surface 4b and the intersection line of the plane with the horizontal plane) is acquired, which is included in the operation instruction input to the input unit. In the next third acquisition step C2, an output value α (detected front-rear tilt) of the first angle sensor is acquired. In the next third judgment step C3, it is judged whether the output value α is equal to the target value θ. If it is judged to be equal (C3: YES), the process returns to the second acquisition step C1. On the other hand, if it is judged to be not equal (there is a difference) (C3: NO), the process proceeds to the second calculation step C4. In the second calculation step C4, the movement amount of the moving body 2 located in front of the fixed link 3 and the movement amount of the moving body 2 located behind the fixed link 3 are calculated so that the inclination of the third member 324 relative to the second member 322 of the movable joint 32 becomes θ. In the next second control step C5, the motor 21 of the moving body 2 located in front of the fixed link 3 is controlled so that the moving body 2 approaches or moves away from the center of the base body 11 by the calculated distance. In addition, the motor 21 of the moving body 2 located behind the fixed link 3 is controlled so that the moving body 2 moves away or moves toward the center of the base body 11 until the inclination of the mounting surface 4b of the rotating body 4 in the front-rear direction (output value α of the first angle sensor) becomes equal to the target value θ. In the next fourth judgment step C6, it is judged whether the working robot 200 is working. If it is judged that the working robot 200 is working (C6: YES), the process returns to the second acquisition step C1. On the other hand, if it is determined that work is not being performed (C6: NO), the second front-rear direction process ends.

[0057] In the second left-right direction process, the processor 84 repeatedly executes the second acquisition step D1, the third acquisition step D2, the third judgment step D3, the second calculation step D4, the second control step D5, and the fourth judgment step D6. In the first second acquisition step D1, a target value of the left-right tilt of the mounting surface 4b (the angle φ between the intersection line of the plane extending in the left-right and vertical directions with the mounting surface 4b and the intersection line of the plane with the horizontal plane) is acquired, which is included in the operation instruction input to the input unit. In the next third acquisition step D2, an output value β (detected left-right tilt) of the second angle sensor is acquired. In the next third judgment step D3, it is judged whether the output value β is equal to the target value φ. If it is judged to be equal (D3: YES), the process returns to the second acquisition step D1. On the other hand, if it is judged to be not equal (there is a difference) (D3: NO), the process proceeds to the second calculation step D4. In the second calculation step D4, the movement amount of the moving body 2 located to the right of the fixed link 3 and the movement amount of the moving body 2 located to the left are calculated so that the inclination of the second member 322 relative to the first member 321 of the movable joint 32 is φ. In the next second control step D5, each motor 21 of the moving body 2 located to the right of the fixed link 3 is controlled so that the moving body 2 approaches or moves away from the center of the base body 11 by the calculated distance. In addition, the motor 21 of the moving body 2 located to the left of the fixed link 3 is controlled so that the moving body 2 moves away or moves toward the center of the base body 11 until the left-right inclination of the mounting surface 4b of the rotating body 4 (output value β of the first angle sensor) becomes equal to the target value φ. In the next fourth judgment step D6, it is judged whether the transporting device 100 is working. If it is judged that the transporting device 100 is working (D6: YES), the process returns to the second acquisition step D1. On the other hand, if it is determined that the user is not working (D6: NO), the second left / right direction process ends.

[0058] [tool] The tool 200b is attached to the lower surface of the rotating body 4 of the parallel link mechanism 200a. Although a hand grinder is illustrated as an example of the tool 200b in Fig. 8, the tool 200b is not limited to this. The tool 200b may be, for example, a drill, a cutter, a driver, a hammer, a welding torch, a suction cup, a gripping member, or the like.

[0059] <Operation of working robot (parallel link mechanism)> In the working robot 200 configured as described above, a tool 200b is attached below the mounting surface 4b of the rotating body 4. As described above, in the working robot 200 (parallel link mechanism 200a), the center of the rotating body 4 is supported by the fixed link 3. That is, the working robot 200 (parallel link mechanism 100a) has high overall rigidity. Also, in the working robot 200 (parallel link mechanism 200a), the load of the tool 200b acting on the center of the rotating body 4 is borne by the fixed link 3 instead of the movable link 5. For this reason, the working robot 200 can move even a heavy tool 200b.

[0060] When the user operates an operation unit (not shown), the tool 200b starts to operate. If the tool 200b is a hand grinder, it rotates a disk (blade, grindstone). When the tool 200b starts to operate, the processor 84 repeatedly acquires an operation instruction. Also, when the tool 200b starts to operate, the sensor 6 repeatedly detects the inclination of the mounting surface 4b of the rotating body 4 with respect to the horizontal plane. When the working robot 200 acquires an operation instruction to rotate the rotating body 4, the processor 84 controls the motor 21 of the moving body 2 to move the moving body 2. When the moving body 2 moves, the movable link 5 moves, and the rotating body 4 rotates around the connection part with the fixed link 3. As described above, the four guide members 124 used to move the moving body 2 extend from the center of the base main body 11 forward, backward, and both left and right sides. Therefore, the parallel link mechanism 200a can tilt the rotating body 4 in any direction.

[0061] Operational instructions from a user may be sent suddenly and may change frequently. However, as described above, the motor 21 is a direct drive motor. Therefore, the working robot 200 (parallel link mechanism 200a) can move the movable link 5 at high speed and with high accuracy and tilt the rotating body 4 to a desired angle, even when an operational instruction is received suddenly or when the operational instructions change frequently.

[0062] If there is no change in the operation instructions while the working robot 200 (parallel link mechanism 100a) is working, the processor 84 stops the power supply to the motor 21. As described above, the motor 21 is a direct drive motor. Therefore, the working robot 200 (parallel link mechanism 100a) can fix the moving body 2 (the base end of the link) in place simply by stopping the power supply to the motor 21.

[0063] <Effects of parallel link mechanisms and work robots> As described above, the parallel link mechanism 200a described above is inclined so that the guide member 124 is lowered (closer to the rotating body 4) as it moves away from the center of the base body 11. Therefore, the parallel link mechanism 200a is more compact than a conventional parallel link mechanism in which guide members of the same length are arranged horizontally, similar to the parallel link mechanism 100a according to the first embodiment. Moreover, the parallel link mechanism 200a can make the length of the guide member 124 (the movable range of the moving body 2) longer than that of a conventional parallel link mechanism by increasing the horizontal width within a range not exceeding that of a conventional parallel link mechanism. Moreover, the parallel link mechanism 100a can make the rotation width of the rotating body 4 when the moving body 2 is moved a predetermined distance larger than that of a conventional parallel link mechanism in which the guide members are arranged horizontally when the moving body is moved the same distance. In this way, the parallel link mechanism 200a can increase the rotation width of the rotating body 4 without increasing the size of the mechanism.

[0064] Furthermore, by being equipped with the parallel link mechanism 200a, the working robot 200 can tilt the tool 200b to an extent (for example, about 20°) that would be difficult for conventional working robots to perform, without making the device larger. Therefore, the working robot 200 uses a mechanism that tilts the object to be machined by the tool 200b, eliminating the need to greatly tilt the tool 200b relative to the object. Furthermore, the working robot 200 can automate at least a portion of the finishing process that was previously performed manually but could not be performed by conventional working robots.

[0065] <Modifications of the first and second embodiments> The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. In other words, embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the technical scope of the present invention.

[0066] For example, some or all of the functions of the processor can be realized by a logic circuit. For example, an integrated circuit in which a logic circuit that functions as each of the control blocks is formed is also included in the scope of the present invention. In addition, the functions of each of the control blocks can be realized by, for example, a quantum computer.

[0067] 〔summary〕 a plurality of movable links each having a base end fixed to the center of the base body and a tip end connected to the periphery of the rotating body, the plurality of movable links each having a base end connected to the center of the base body and a tip end connected to the periphery of the rotating body, the plurality of movable links each having a base end connected to the moving ...

[0068] A parallel link mechanism according to aspect 2 of the present invention may be configured as follows: in aspect 1 above, the fixed link extends upward from the center of the base body, the rotating body is arranged above the base and connected to the tip of the fixed link at the center of the underside, and serves as a loading platform on whose upper surface a load can be placed, and at least one of the plurality of guide members is inclined so as to rise as it moves away from the center of the base body, and when the processor detects inclination of the rotating body, it controls the movement of the plurality of moving bodies so as to eliminate the inclination of the rotating body.

[0069] A parallel link mechanism according to aspect 3 of the present invention may be configured as follows: in aspect 1 above, the fixed link extends downward from the center of the base body, the rotating body is arranged below the base and connected to the tip of the fixed link at the center of the upper surface, a tool can be attached to the underside, and at least one of the multiple guide members is inclined so as to descend as it moves away from the center of the base body, and when the processor obtains an operation instruction for the rotating body, it controls the movement of the multiple moving bodies so that the inclination of the rotating body with respect to the horizontal plane becomes a magnitude corresponding to the operation instruction.

[0070] A parallel link mechanism according to a fourth aspect of the present invention may be configured as in any one of the first to third aspects above, wherein the guide member includes a rack extending parallel to the guide member, and each moving body includes a motor that rotates under the control of the processor, and a pinion that meshes with the rack and rotates in response to the rotation of the motor.

[0071] A parallel link mechanism according to a fifth aspect of the present invention may be configured as in the fourth aspect, wherein the motor is a direct drive motor.

[0072] The parallel link mechanism according to a sixth aspect of the present invention may be configured in such a way that in the fourth or fifth aspect, the moving body includes a reducer between the motor and the pinion.

[0073] A parallel link mechanism according to a seventh aspect of the present invention may be configured in any one of the above-mentioned fourth to sixth aspects so that the moving body is provided with an encoder for detecting the direction and angle of rotation of the motor, and the processor rotates the motor based on the detection result by the encoder.

[0074] A parallel link mechanism according to aspect 8 of the present invention may be configured in any one of aspects 1 to 7 above, wherein the multiple guide members extend from the center of the base body forward, backward and to both sides, and are all inclined so as to approach the rotating body the further away from the center of the base body, and each tip of the multiple movable links is connected to each of the front-rear, back-right and left-right ends of the rotating body, respectively.

[0075] A parallel link mechanism according to a ninth aspect of the present invention may be configured as in any one of the first to eighth aspects above, wherein the tip of the fixed link is a movable joint having an axis portion at the center of the rotating body and extending in a direction perpendicular to the extension direction of the fixed link, and the rotating body is connected to the fixed link so as to be rotatable around the axis portion as a rotation axis.

[0076] A parallel link mechanism according to aspect 10 of the present invention may be configured as in aspect 9 above, wherein the movable joint has a first shaft portion extending in the front-to-rear direction and a second shaft portion extending in the left-to-right direction, and the rotating body is connected to the fixed link so as to be rotatable about the first shaft portion as a rotation axis and so as to be rotatable about the second shaft portion as a rotation axis.

[0077] A transport device according to an eleventh aspect of the present invention may be configured to include a moving mechanism capable of moving on the ground, and the parallel link mechanism according to the second aspect above mounted on the moving mechanism.

[0078] A working robot according to a twelfth aspect of the present invention may be configured to include the parallel link mechanism according to the third aspect above, and a tool attached to the underside of the rotating body of the parallel link mechanism. [Explanation of symbols]

[0079] 100: conveying device, 100a: parallel link mechanism, 1: base, 11: base body, 111: fixed member, 111a: support portion, 12: support member, 121: first support column, 122: second support column, 123: beam portion, 124: guide member, 125: rack, 2: moving body, 21: motor, 22: pinion, 23: reducer, 24: connecting portion, 25: encoder, 3: fixed link, 31: link body, 32: movable joint, 321: first member, 322: second member, 323: first axis part, 324: third member, 325: second shaft part, 4: platform, 4: rotating body (platform), 4a: placement surface, 4b: mounting surface, 5: movable link, 6: sensor, 7: power source, 8, 8A: control board, 81: input / output interface, 82, 82A: primary memory, 83: secondary memory, 84: processor, 85: bus, 100b: moving mechanism, 101: power source, 102: caterpillar track, 102a: cover plate, 200: work robot, 200a: parallel link mechanism, 9: input part, 200b: tool

Claims

1. A base including a base body and a plurality of guide members each extending in a direction different from each other, the guide members being in a direction away from a central portion of the base body toward a peripheral portion; A plurality of movable bodies movable along the respective guide members; a fixed link having a base end fixed to a central portion of the base body and extending in a direction away from the base; a rotating body having a center portion connected to a tip portion of the fixed link and capable of rotating around the tip portion; a plurality of movable links each having a base end connected to the movable body and a tip end connected to a peripheral portion of the rotating body, the movable links rotating the rotating body in response to movement of the movable body; A sensor that detects the inclination of the rotating body with respect to a horizontal plane; a processor that controls the movement of the plurality of movable bodies based on the detection result of the sensor so that the inclination of the rotating body with respect to the horizontal plane is a desired magnitude; Equipped with At least one of the plurality of guide members is inclined so as to approach the rotating body as it moves away from the center portion of the base body. A parallel link mechanism characterized by the above.

2. The fixed link extends upward from a central portion of the base body, the rotating body is disposed above the base, and is connected at a center of a lower surface thereof to a tip end of the fixed link, and is a loading platform on an upper surface of which a load can be placed; At least one of the plurality of guide members is inclined so as to rise as it moves away from the center of the base body, When the processor detects a tilt of the rotating body, the processor controls the movements of the plurality of moving bodies so as to eliminate the tilt of the rotating body.

2. The parallel link mechanism according to claim 1 .

3. The fixed link extends downward from a central portion of the base body, the rotating body is disposed below the base, and is connected to a tip end of the fixed link at a center of an upper surface thereof, and a tool can be attached to a lower surface thereof; At least one of the plurality of guide members is inclined so as to descend as it moves away from the center of the base body, when the processor acquires an instruction to move the rotating body, the processor controls the movements of the plurality of moving bodies so that an inclination of the rotating body with respect to the horizontal plane corresponds to the instruction to move the rotating body.

2. The parallel link mechanism according to claim 1 .

4. The guide member includes a rack extending parallel to the guide member, Each mobile unit is a motor that rotates under the control of the processor; a pinion that meshes with the rack and rotates in response to rotation of the motor; Equipped with 4. The parallel link mechanism according to claim 1, wherein the parallel link mechanism is a parallel link mechanism.

5. The motor is a direct drive motor.

5. The parallel link mechanism according to claim 4.

6. The moving body includes a reducer between the motor and the pinion.

5. The parallel link mechanism according to claim 4.

7. the movable body includes an encoder that detects a rotation direction and a rotation angle of the motor; The processor rotates the motor based on the detection result by the encoder.

5. The parallel link mechanism according to claim 4.

8. the plurality of guide members extend from a center portion of the base body toward the front, rear, left and right, respectively, and are all inclined so as to approach the rotating body as they move away from the center portion of the base body, The tip ends of the plurality of movable links are connected to the front, rear, left and right ends of the rotating body, respectively.

2. The parallel link mechanism according to claim 1 .

9. a tip end of the fixed link is a movable joint having a shaft portion extending in a direction perpendicular to an extension direction of the fixed link at a center of the rotating body, The rotating body is connected to the fixed link so as to be rotatable about the shaft portion as a rotation axis.

2. The parallel link mechanism according to claim 1 .

10. The movable joint is A first shaft portion extending in the front-rear direction; A second shaft portion extending in the left-right direction; having The rotating body is connected to the fixed link so as to be rotatable about the first shaft portion as a rotation axis and so as to be rotatable about the second shaft portion as a rotation axis.

10. The parallel link mechanism according to claim 9.

11. A movement mechanism capable of moving on the ground; The parallel link mechanism according to claim 2, which is mounted on the movement mechanism; Equipped with A conveying device characterized by:

12. The parallel link mechanism according to claim 3 ; a tool attached to a lower surface of the rotating body of the parallel link mechanism; Equipped with A working robot characterized by:

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