Autonomous mobile body

Abstract

To provide an autonomous mobile body capable of absorbing greater force that acts on a loaded object.SOLUTION: An autonomous mobile body of the present embodiment includes: a travelling unit that has a driving wheel and a chassis; a transportation unit that has a top panel, a pendulum mechanism of allowing the top panel to swing in a front-back and a right-left directions, and a rotation mechanism of allowing the pendulum mechanism to rotate around a vertical shaft, and that is arranged at a top of the travelling unit; and a control part that calculates acceleration of the autonomous mobile body and, in a case where the calculated acceleration exceeds a threshold value, performs control of allowing the rotation mechanism to rotate the pendulum mechanism in a manner such that the front-back and left-right directions of the transportation unit are oblique to a front-back direction of the traveling unit.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an autonomous moving body. [Background technology]

[0002] Conventionally, there has been research and development of autonomous mobile robots capable of carrying objects such as food, drink, luggage, etc. The autonomous mobile robot can prevent the object from falling off, for example, during acceleration / deceleration or while traveling on an inclined surface, by making the part on which the object is placed move in a pendulum motion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-104439 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional configuration, the range of the pendulum motion is limited, so that when a large force such as vibration, swing, or centrifugal force acts on an object, the force may not be fully absorbed by the pendulum motion.

[0005] Therefore, the present invention has been made in consideration of the above, and provides an autonomous moving body that can absorb a larger force acting on an object placed on it. [Means for solving the problem]

[0006] The autonomous moving body of this embodiment comprises a running unit having drive wheels and a chassis, a top plate, a pendulum mechanism that causes the top plate to move in a pendulum manner in the forward / backward and left / right directions, and a rotation mechanism that rotates the pendulum mechanism around an axis in the vertical direction, and is arranged on top of the running unit; and a control unit that calculates the acceleration of the autonomous moving body, and when the calculated acceleration exceeds a threshold value, controls the rotation mechanism to rotate the pendulum mechanism so that the forward / backward and left / right directions of the transport unit are inclined relative to the forward / backward direction of the running unit. Effect of the Invention

[0007] According to this embodiment, it is possible to absorb a larger force acting on the placed object. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the structure of an autonomous mobile robot according to the first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating a functional configuration of the autonomous running robot according to the first embodiment. [Diagram 3] FIG. 3 is a plan view showing the normal state of the autonomous mobile robot of the first embodiment. [Figure 4] FIG. 4 is a plan view showing the autonomous mobile robot of the first embodiment in an oblique orientation. [Diagram 5] FIG. 5 is a flowchart showing the processing by the control unit of the autonomous running robot of the first embodiment. [Figure 6] FIG. 6 is a plan view showing the autonomous mobile robot of the second embodiment in an oblique orientation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (First embodiment) Hereinafter, an autonomous running robot (autonomous moving body) according to a first embodiment will be described with reference to the drawings. First, the structure and functional configuration of the autonomous running robot R will be described with reference to Figs. 1 and 2. The autonomous running robot R is an example of an autonomous moving body. Fig. 1 is a diagram showing the structure of the autonomous running robot R according to the first embodiment. Fig. 2 is a diagram showing the functional configuration of the autonomous running robot R according to the first embodiment.

[0010] 1(a) is an external view of an autonomous mobile robot R. The autonomous mobile robot R can carry objects such as food, drink, and luggage, and moves autonomously within mobile environments such as restaurants, homes, facilities, warehouses, factories, and outdoors.

[0011] The autonomous mobile robot R includes a carrying unit 1 and a traveling unit 2. The traveling unit 2 can move straight ahead and turn. The carrying unit 1 is disposed on the upper part of the traveling unit 2.

[0012] The traveling unit 2 has four drive wheels 21 and a chassis 22. The four drive wheels 21 are attached to substantially parallel axles. In the first embodiment, the direction in which the axles extend and the orientation of the drive wheels 21 are substantially constant. The chassis 22 has a housing that is substantially rectangular parallelepiped-shaped with rounded corners. The drive wheels 21 are connected to the chassis 22 via the above-mentioned axles.

[0013] 1 is the front-rear direction of the traveling unit 2 and also the front-rear direction of the autonomous traveling robot R. For example, the traveling front-rear direction Yr is the traveling direction of the traveling unit 2 when the four drive wheels 21 rotate at an equal number of rotations. The arrow of the traveling front-rear direction Yr in FIG. 1 indicates the forward direction of the traveling unit 2 in the traveling front-rear direction Yr.

[0014] The left-right traveling direction Xr indicated by the arrow in Fig. 1 is the left-right direction of the traveling unit 2 and also the left-right direction (width direction) of the autonomous traveling robot R. For example, the left-right traveling direction Xr indicates a direction perpendicular to the forward-rearward traveling direction Yr and a direction parallel to the ground. The arrow of the left-right traveling direction Xr in Fig. 1 indicates the right direction of the traveling unit 2 in the left-right traveling direction Xr.

[0015] The front face 23 of the propulsion unit 2 is an end of the propulsion unit 2 in the forward direction of the propulsion unit 2. The front face 23 is provided, for example, on the chassis 22. The front face 23 faces in the forward direction of the propulsion unit 2 as a whole.

[0016] The transport unit 1 comprises an upper body 11 and a lower body 12. The housing of the upper body 11 is fixed to a pendulum mechanism 14 (FIG. 1(b)) and moves in accordance with the movement of the pendulum mechanism 14. The upper body 11 has a top plate 111. The top plate 111 has an upper surface 111a that faces upwardly of the autonomous mobile robot R. The upper surface 111a is formed to be approximately flat, but may be formed with projections and recesses, for example. The housing of the lower body 12 is fixed to a rotation mechanism 13 (FIG. 1(b)) and rotates in accordance with the rotational movement of the rotation mechanism 13.

[0017] Fig. 1(b) is a diagram showing the internal structure of the carrying unit 1 of the autonomous mobile robot R. In other words, Fig. 1(b) does not show the housing of the upper body 11 and the housing of the lower body 12 in Fig. 1(a). The carrying unit 1 includes a rotation mechanism 13 and a pendulum mechanism 14.

[0018] The rotation mechanism 13 is disposed on the upper part of the chassis 22. The rotation mechanism 13 is a mechanism for rotating the pendulum mechanism 14 around an axis Z in the vertical direction of the autonomous traveling robot R. The axis Z is a virtual central axis of the rotational movement of the rotation mechanism 13.

[0019] The pendulum mechanism 14 is disposed above the rotation mechanism 13. The pendulum mechanism 14 is a mechanism for causing the upper body 11 including the top plate 111 to perform pendulum motion in the forward / backward direction Yt during transportation and the left / right direction Xt during transportation.

[0020] The transport front-rear direction Yt indicated by the arrow in Fig. 1 is the front-rear direction of the transport unit 1. Usually, the transport front-rear direction Yt is set to coincide with the travel front-rear direction Yr. The arrow of the transport front-rear direction Yt in Fig. 1 indicates the front direction of the transport unit 1 in the transport front-rear direction Yt.

[0021] The left-right direction Xt of transport indicated by the arrow in Fig. 1 is the left-right direction of the transport unit 1. For example, the left-right direction Xt of transport indicates a direction perpendicular to the front-rear direction Yt of transport and parallel to the ground. The arrow of the left-right direction Xt of transport in Fig. 1 indicates the right direction of the transport unit 1 in the left-right direction Xt of transport.

[0022] When the rotation mechanism 13 rotates the pendulum mechanism 14 about the axis Z, the transport front-rear direction Yt and the transport left-right direction Xt also rotate about the axis Z. That is, the transport front-rear direction Yt can be set to be different from the travel front-rear direction Yr.

[0023] The front face 15 of the carrying unit 1 (FIG. 1(a)) is the end of the carrying unit 1 in the forward direction of the carrying unit 1. The front face 15 is provided, for example, on the housing of the lower body 12. The front face 15 faces in the forward direction of the carrying unit 1 as a whole.

[0024] The pendulum mechanism 14 includes a front-to-rear pendulum mechanism 141 and a left-to-right pendulum mechanism 142. The front-to-rear pendulum mechanism 141 is a pendulum mechanism for tilting the upper body 11 including the top plate 111 in the front-to-rear direction Yt during transportation. The left-to-right pendulum mechanism 142 is a pendulum mechanism for tilting the upper body 11 including the top plate 111 in the left-to-right direction Xt during transportation.

[0025] Each of the front-rear pendulum mechanism 141 and the left-right pendulum mechanism 142 includes, for example, a guide rail extending in a substantially arc shape and a roller that engages with the guide rail. The guide rail rotates about a virtual central axis of the guide rail in conjunction with the rotation of the roller.

[0026] In the left-right pendulum mechanism 142, the central axis of the guide rail extends in the front-rear direction Yt during transport, the guide rail is connected to the upper body 11, and the rollers are connected to the front-rear pendulum mechanism 141. Therefore, when the rollers of the left-right pendulum mechanism 142 rotate the guide rail, the upper body 11 performs pendulum motion relative to the front-rear pendulum mechanism 141.

[0027] In the front-rear pendulum mechanism 141, the central axis of the guide rail extends in the left-right direction Xt during transport, the guide rail is connected to the left-right pendulum mechanism 142, and the rollers are connected to the chassis 22. Therefore, when the rollers of the front-rear pendulum mechanism 141 rotate the guide rail, the left-right pendulum mechanism 142 and the upper body 11 perform pendulum motion relative to the chassis 22.

[0028] As described above, the pendulum mechanism 14 can cause the upper body 11 to perform pendulum motion around two central axes extending in directions perpendicular to each other. The pendulum mechanism 14 may also cause the upper body 11 to perform pendulum motion around three or more central axes extending in directions intersecting each other.

[0029] When the left-right pendulum mechanism 142 causes the upper body 11 to perform the maximum pendulum motion, and when the front-rear pendulum mechanism 141 causes the left-right pendulum mechanism 142 and the upper body 11 to perform the maximum pendulum motion, the rollers come into contact with the stoppers of the guide rails. That is, the range of the pendulum motion of the upper body 11 is limited by the stoppers in both the forward-rear direction Yt of transport and the left-right direction Xt of transport. The range of the pendulum motion of the upper body 11 may or may not be limited by other methods.

[0030] An object to be transported by the autonomous mobile robot R is placed on an upper surface 111a (FIG. 1(a)) of a top board 111. A mark 112 is provided on the upper surface 111a. The mark 112 makes it possible to easily identify the forward / rearward direction Yt and the left / right direction Xt of transport.

[0031] As shown in FIG. 2, the traveling unit 2 includes a traveling drive unit 24, a position sensor 25, an object detection sensor 26, and a traveling ECU 27.

[0032] The traveling drive unit 24 includes an electric motor that rotates and drives the drive wheels 21. When the traveling drive unit 24 includes four electric motors, the output shafts of the electric motors may be connected to the drive wheels 21 as axles.

[0033] The position sensor 25 is a sensor that acquires data for the travel ECU 27 to estimate the position of the autonomous traveling robot R. The position sensor 25 is composed of, for example, a GPS (Global Positioning System) sensor, a rotational angular velocity sensor of the drive wheels 21, etc., and transmits a detection signal to the travel ECU 27.

[0034] The object detection sensor 26 is a sensor that detects objects (hereinafter, also referred to as "obstacles") around the autonomous traveling robot R. The object detection sensor 26 is composed of, for example, a LiDAR (Light Detection And Ranging) or a millimeter wave sensor, and transmits a detection signal to the traveling ECU 27. Note that the object detection sensor 26 may also be composed of a camera, an ultrasonic sensor, an infrared sensor, or the like, or may be a combination of a plurality of means.

[0035] The rotation mechanism 13 includes a rotation drive unit 131 , a rotation angle sensor 132 , and a rotation ECU 133 .

[0036] The rotary drive unit 131 includes an actuator that rotates the pendulum mechanism 14. For example, a main body of the actuator is connected to the chassis 22, and an output shaft of the actuator is connected to the pendulum mechanism 14. The output shaft of the actuator is connected to the lower body 12 and rotates around the axis Z relative to the main body.

[0037] The rotation angle sensor 132 is a sensor that detects the rotation angle of the rotation mechanism 13. For example, the rotation angle sensor 132 detects the rotation angle of an output shaft relative to a main body of the actuator of the rotation drive unit 131. Furthermore, the rotation angle sensor 132 transmits a detection signal to the rotation ECU 133.

[0038] The pendulum mechanism 14 includes a left-right pendulum drive unit 143 , a front-rear pendulum drive unit 144 , a position sensor 145 , an acceleration sensor 146 , and a pendulum ECU 147 .

[0039] The horizontal pendulum drive unit 143 includes an actuator that rotates the roller of the horizontal pendulum mechanism 142. When the horizontal pendulum drive unit 143 rotates the roller, the guide rail of the horizontal pendulum mechanism 142 rotates, and the horizontal pendulum mechanism 142 causes the upper body 11 to perform pendulum motion in the horizontal transport direction Xt.

[0040] For example, when the autonomous mobile robot R turns in the left-right direction Xr, acceleration in the left-right direction Xr and centrifugal force accompanying the acceleration are generated in the autonomous mobile robot R. The left-right pendulum drive unit 143 is a mechanism for causing the upper body 11 to perform pendulum motion in the left-right direction Xt of transport to offset the effect of the centrifugal force so that an object placed on the upper surface 111a of the top board 111 does not fall in the left-right direction Xr of travel due to the effect of the centrifugal force.

[0041] The front-rear pendulum drive unit 144 includes an actuator that rotates the roller of the front-rear pendulum mechanism 141. When the front-rear pendulum drive unit 144 rotates the roller, the guide rail of the front-rear pendulum mechanism 141 rotates, and the front-rear pendulum mechanism 141 causes the upper body 11 to perform pendulum motion in the front-rear transport direction Yt.

[0042] For example, when the autonomous mobile robot R accelerates or decelerates in the traveling front-rear direction Yr, acceleration in the traveling front-rear direction Yr occurs in the autonomous mobile robot R. The front-rear pendulum drive unit 144 is a mechanism for causing the upper body 11 to perform pendulum motion in the transportation front-rear direction Yt to offset the effect of the acceleration so that an object placed on the upper surface 111a of the top board 111 does not fall in the traveling front-rear direction Yr due to the effect of the acceleration.

[0043] The left-right pendulum drive unit 143 and the front-back pendulum drive unit 144 can be controlled in parallel. Therefore, even if acceleration occurs in any direction around 360 degrees in the autonomous traveling robot R, by controlling the left-right pendulum drive unit 143 and the front-back pendulum drive unit 144 in parallel to cancel out the effect of the acceleration, it is possible to prevent an object placed on the upper surface 111a of the tabletop 111 from falling off.

[0044] The position sensor 145 is a sensor that acquires data for estimating the position of the pendulum mechanism 14. The position sensor 145 is constituted by, for example, a rotational angular velocity sensor, and transmits a detection signal to the pendulum ECU 147. Note that the position sensor 145 may be provided for each of the front-rear pendulum mechanism 141 and the left-right pendulum mechanism 142.

[0045] The acceleration sensor 146 detects the acceleration generated in the pendulum mechanism 14 and transmits a detection signal to the pendulum ECU 147. The acceleration sensor 146 can detect, for example, the acceleration in the forward / backward direction Yt during transportation, the acceleration in the left / right direction Xt during transportation, and the acceleration in the up / down direction of the autonomous traveling robot R.

[0046] The autonomous traveling robot R further includes a control unit C. The control unit C includes a traveling ECU 27 of the traveling unit 2, a rotation ECU 133 of the rotation mechanism 13, and a pendulum ECU 147 of the pendulum mechanism 14. Note that the control unit C is not limited to this example, and may be one or two ECUs, and may further include various other components.

[0047] The travel ECU 27, the rotation ECU 133, and the pendulum ECU 147 are each an information processing device configured using various hardware and software, and are configured using, for example, a CPU (Central Processing Unit), a memory, an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), etc. The travel ECU 27, the rotation ECU 133, and the pendulum ECU 147 can communicate with each other via a CAN (Controller Area Network), and transmit and receive necessary information.

[0048] The travel ECU 27 executes various controls related to the traveling unit 2. For example, the travel ECU 27 estimates the current position of the autonomous traveling robot R based on a detection signal acquired from the position sensor 25. The travel ECU 27 also recognizes obstacles around the autonomous traveling robot R based on a detection signal acquired from the object detection sensor 26. The travel ECU 27 also generates a traveling route from the current position to the destination based on the current position, the destination, and the positions of the obstacles. The travel ECU 27 also controls the traveling drive unit 24 to make the traveling unit 2 (and thus the autonomous traveling robot R) travel along the traveling route.

[0049] The pendulum ECU 147 executes various controls related to the pendulum mechanism 14. Based on detection signals acquired from the position sensor 145 and the acceleration sensor 146, the pendulum ECU 147 controls the left-right pendulum drive unit 143 and the front-rear pendulum drive unit 144 to make the upper body 11 perform pendulum motion so that an object placed on the upper surface 111a of the top board 111 does not fall due to the acceleration of the autonomous traveling robot R.

[0050] Gravity acts on an object placed on the top surface 111a of the tabletop 111. Furthermore, when the autonomous mobile robot R accelerates or decelerates in the forward / backward direction Yr, an inertial force acts on the object. Furthermore, when the autonomous mobile robot R turns in the left / right direction Xr, a centrifugal force acts on the object. If the force (acceleration) acting on an object placed on the top surface 111a includes a component parallel to the top surface 111a, the object may fall off the top surface 111a.

[0051] Based on the detection signal of the acceleration sensor 146, the pendulum ECU 147 calculates the acceleration of the autonomous traveling robot R in the forward / backward transport direction Yt, the acceleration in the left / right transport direction Xt, the acceleration in the forward / backward travel direction Yr, the acceleration in the left / right travel direction Xr, and the acceleration in the up / down direction of the autonomous traveling robot R. Based on the travel route generated by the travel ECU 27, the pendulum ECU 147 may calculate the acceleration that reflects the acceleration / deceleration and turning schedule.

[0052] The pendulum ECU 147 causes the pendulum mechanism 14 (the front-rear pendulum mechanism 141 and the left-right pendulum mechanism 142) to perform pendulum motion of the upper body 11 including the top plate 111 so that the direction of the force (acceleration) acting on the object placed on the top surface 111a of the top plate 111 approaches a direction perpendicular to the top surface 111a. When the direction of the force (acceleration) acting on the object placed on the top surface 111a of the top plate 111 is perpendicular to the top surface 111a, the object can come to rest substantially on the top surface 111a.

[0053] As described above, the pendulum ECU 147 causes the pendulum mechanism 14 to perform pendulum motion of the upper body 11 so as to absorb the force (acceleration) acting on the object placed on the upper surface 111a of the tabletop 111. In this way, the pendulum ECU 147 can prevent the object placed on the upper surface 111a of the tabletop 111 from falling off.

[0054] The rotation ECU 133 executes various controls related to the rotation mechanism 13. For example, when the acceleration of the autonomous traveling robot R increases due to acceleration / deceleration, turning, vibration, or swinging, the rotation ECU 133 causes the rotation mechanism 13 to put the pendulum mechanism 14 in an oblique orientation state.

[0055] Fig. 3 is a plan view showing the normal state of the autonomous running robot R of the first embodiment. Fig. 4 is a plan view showing the diagonal orientation state of the autonomous running robot R of the first embodiment. For example, the rotation ECU 133 acquires the acceleration of the autonomous running robot R in the traveling front-rear direction Yr and the traveling left-right direction Xr calculated by the pendulum ECU 147. When the acceleration acquired from the pendulum ECU 147 exceeds a threshold value, the rotation ECU 133 causes the rotation mechanism 13 to rotate the pendulum mechanism 14, causing the autonomous running robot R to change from the normal state of Fig. 3 to the diagonal orientation state of Fig. 4.

[0056] 3, in the normal state, the rotation ECU 133 positions the pendulum mechanism 14, the upper body 11, and the lower body 12 in the rotation mechanism 13 so that the traveling longitudinal direction Yr and the transport longitudinal direction Yt coincide with each other. Note that in the normal state, the rotation ECU 133 may rotate (swing) the pendulum mechanism 14, the upper body 11, and the lower body 12 around the axis Z based on other control. That is, in the normal state, the traveling longitudinal direction Yr and the transport longitudinal direction Yt may be different from each other.

[0057] 4, when the rotation ECU 133 causes the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the pendulum mechanism 14 is in an oblique state, the transport longitudinal direction Yt and the transport lateral direction Xt become oblique with respect to the travel longitudinal direction Yr. For example, in the oblique state, the transport longitudinal direction Yt is shifted by about 45° around the axis Z with respect to the travel longitudinal direction Yr.

[0058] In other words, when the rotation ECU 133 causes the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the pendulum mechanism 14 is in an oblique state, the transport front-rear direction Yt and the transport left-right direction Xt become oblique with respect to the traveling direction (the forward direction of the traveling unit 2) of the traveling unit 2. In other words, in the oblique state, the center of the front face 15 of the transport unit 1 is shifted around the axis Z with respect to the center of the front face 23 of the traveling unit 2.

[0059] The above threshold value is, for example, the maximum acceleration at which the pendulum mechanism 14 in a normal state can absorb the force acting on an object placed on the upper surface 111a of the top plate 111. In other words, the threshold value is the acceleration of the autonomous traveling robot R at which the direction of the force acting on the object becomes perpendicular to the upper surface 111a when the pendulum mechanism 14 causes the upper body 11 including the top plate 111 to perform maximum pendulum motion in at least one of the forward / rearward transport direction Yt and the left / right transport direction Xt. For example, the threshold value is an acceleration at which at least one of the rollers of the forward / rearward pendulum mechanism 141 and the left / right pendulum mechanism 142 comes into contact with a stopper. Note that the threshold value is not limited to this example, and may be smaller than the above acceleration. The threshold value is set in advance and stored, for example, in a memory of the rotation ECU 133.

[0060] Hereinafter, a case will be described in which the acceleration of the autonomous traveling robot R in the traveling front-rear direction Yr due to acceleration / deceleration slightly exceeds the threshold. In this case, if the pendulum mechanism 14 is in a normal state, the rollers of the front-rear pendulum mechanism 141 abut against the stoppers of the guide rail. However, in this embodiment, when the acceleration exceeds the threshold, the rotation ECU 133 causes the rotation mechanism 13 to rotate the pendulum mechanism 14 by about 45°, so that the pendulum mechanism 14 is in an oblique orientation state.

[0061] 4, an acceleration a exceeding a threshold value acts on the autonomous mobile robot R in the forward / backward direction Yr of travel. However, because the transport unit 1 is in an oblique orientation, the acceleration a is decomposed into an acceleration in the forward / backward direction Yt of travel (hereinafter also referred to as the "forward / backward component ay") and an acceleration in the left / right direction Xt of travel (hereinafter also referred to as the "left / right component ax").

[0062] The longitudinal component ay and the lateral component ax are accelerations obtained by dividing the acceleration a by the square root of 2 (ay=a / √2, ax=a / √2), respectively, and are smaller than the acceleration a. Therefore, even if the longitudinal pendulum mechanism 141 causes the upper body 11 to perform pendulum motion so as to absorb the inertial force acting on the object placed on the top board 111 by the longitudinal component ay, the rollers of the longitudinal pendulum mechanism 141 do not come into contact with the stoppers. Also, even if the lateral pendulum mechanism 142 causes the upper body 11 to perform pendulum motion so as to absorb the inertial force acting on the object placed on the top board 111 by the lateral component ax, the rollers of the lateral pendulum mechanism 142 do not come into contact with the stoppers. In other words, even if the acceleration a in the longitudinal direction Yr of travel exceeds the threshold value, the pendulum mechanism 14 can absorb the force acting on the object placed on the upper surface 111a of the top board 111. Although the above example has been described regarding acceleration in the longitudinal direction Yr of travel, the pendulum mechanism 14 can also absorb forces such as centrifugal force that acts on an object due to acceleration in the lateral direction Xr of travel, and forces such as excitation forces that act on an object accompanied by acceleration in both the longitudinal direction Yr of travel and the lateral direction Xr of travel.

[0063] Next, a process performed by the control unit C of the autonomous running robot R will be described with reference to Fig. 5. Fig. 5 is a flowchart showing a process performed by the control unit C of the autonomous running robot R of the first embodiment.

[0064] In step S1, the traveling ECU 27 starts traveling. That is, the traveling ECU 27 generates a traveling route from the current position to the destination based on the current position, the destination, and the positions of obstacles, and causes the traveling drive unit 24 to drive the drive wheels 21 according to the traveling route.

[0065] Next, in step S2, the rotation ECU 133 acquires a detection signal from the acceleration sensor 146.

[0066] Next, in step S3, the rotation ECU 133 calculates the acceleration of the autonomous traveling robot R based on the detection signal of the acceleration sensor 146. The rotation ECU 133 calculates the acceleration in the traveling front-rear direction Yr, the acceleration in the traveling left-right direction Xr, the acceleration in the transportation front-rear direction Yt, the acceleration in the transportation left-right direction Xt, and the acceleration in the up-down direction of the autonomous traveling robot R.

[0067] Next, in step S4, the rotation ECU 133 determines whether or not the acceleration in the traveling longitudinal direction Yr exceeds a threshold value. If Yes, the process proceeds to step S6, and if No, the process proceeds to step S5.

[0068] In step S5, the rotation ECU 133 determines whether the acceleration in the traveling left-right direction Xr exceeds a threshold value, and if Yes, proceeds to step S6, and if No, proceeds to step S7. Note that the threshold value in the traveling front-rear direction Yr and the threshold value in the traveling left-right direction Xr may be the same or different from each other.

[0069] In step S6, the rotation ECU 133 places the pendulum mechanism 14 in an oblique orientation. That is, the rotation ECU 133 causes the rotation mechanism 13 to dispose the pendulum mechanism 14 in a position where the transport longitudinal direction Yt and the transport lateral direction Xt are oblique to the travel longitudinal direction Yr. After step S6, the process proceeds to step S8.

[0070] In step S7, the rotation ECU 133 sets the pendulum mechanism 14 to a normal state. That is, the rotation ECU 133 causes the rotation mechanism 13 to place the pendulum mechanism 14 at a position where the transport longitudinal direction Yt and the travel longitudinal direction Yr coincide with each other. After step S7, the process proceeds to step S8.

[0071] The transition to the oblique state in step S6 and the transition to the normal state in step S7 are performed, for example, by the rotation mechanism 13 placing the pendulum mechanism 14 at a preset position (rotation angle around the Z axis). Note that the transition to the oblique state and the normal state may also be performed by the rotation mechanism 13 rotating the pendulum mechanism 14 a predetermined angle around the Z axis from the current position. In this case, it may be determined whether the state is already oblique before step S6, and whether the state is already normal before step S7, and steps S6 and S7 may be skipped.

[0072] In step S8, the pendulum ECU 147 causes the pendulum mechanism 14 to perform pendulum motion of the upper body 11 including the top plate 111. That is, the pendulum ECU 147 causes the longitudinal pendulum mechanism 141 to perform pendulum motion of the upper body 11 in the longitudinal direction Yt of transport based on the acceleration in the longitudinal direction Yt of transport. Furthermore, the pendulum ECU 147 causes the lateral pendulum mechanism 142 to perform pendulum motion of the upper body 11 in the lateral direction Xt of transport based on the acceleration in the lateral direction Xt of transport.

[0073] Next, in step S9, the travel ECU 27 determines whether or not the autonomous traveling robot R has arrived at the destination. If Yes, the process proceeds to step S10, and if No, the process returns to step S2.

[0074] In step S10, the traveling ECU 27 controls the traveling drive unit 24 to stop, and the traveling of the autonomous traveling robot R ends.

[0075] As described above, the autonomous traveling robot R according to the first embodiment includes the traveling unit 2, the transport unit 1, and the control unit C. The traveling unit 2 has the drive wheels 21 and the chassis 22. The transport unit 1 has a top plate 111, a pendulum mechanism 14, and a rotation mechanism 13, and is disposed on the upper part of the traveling unit 2. The pendulum mechanism 14 causes the top plate 111 to perform pendulum motion in the front-rear direction (transport front-rear direction Yt) and the left-right direction (transport left-right direction Xt) of the transport unit 1. The rotation mechanism 13 rotates the pendulum mechanism 14 around the axis Z in the up-down direction. The control unit C (pendulum ECU 147) calculates the acceleration of the autonomous traveling robot R. Furthermore, when the calculated acceleration exceeds a threshold value, the control unit C (rotation ECU 133) controls the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the transport front-rear direction Yt and the transport left-right direction Xt are inclined with respect to the front-rear direction (travel front-rear direction Yr) of the traveling unit 2. Therefore, as an example, the pendulum mechanism 14 can distribute the direction of the pendulum motion to the forward / backward direction Yt of transport and the left / right direction Xt of transport. For example, the pendulum mechanism 14 can absorb forces such as vibration, swing, and centrifugal force acting on an object placed on the top plate 111 due to the acceleration of the autonomous mobile robot R by causing the top plate 111 to perform pendulum motion. In this case, if the acceleration of the autonomous mobile robot R in the traveling direction (forward / backward direction Yr of transport) of the traveling unit 2 is large and the forward / backward direction Yr of transport coincides with the forward / backward direction Yt of transport, the pendulum motion in the forward / backward direction Yr of transport becomes large. However, if the forward / backward direction Yt of transport and the left / right direction Xt of transport differ from the forward / backward direction Yr of transport, the pendulum mechanism 14 can divide the large pendulum motion in the forward / backward direction Yr of transport into a small pendulum motion in the forward / backward direction Yt of transport and a small pendulum motion in the left / right direction Xt of transport. Therefore, the pendulum mechanism 14 can absorb forces such as larger vibration, swing, and centrifugal force acting on an object placed on the top plate 111. Furthermore, the pendulum mechanism 14 can reduce the amount of movement of the tabletop 111 (the amount of projection of the upper body 11) by reducing the pendulum motion in the forward / backward direction Yt and the left / right direction Xt during transport.

[0076] The control unit C (pendulum ECU 147) controls the pendulum mechanism 14 to make the top plate 111 pendulum so that the direction of the force acting on the object placed on the top surface 111a of the top plate 111 approaches a direction perpendicular to the top surface 111a. The threshold value is the acceleration of the autonomous mobile robot R at which the direction of the force acting on the object becomes perpendicular to the top surface 111a when the pendulum mechanism 14 makes the top plate 111 pendulum to the maximum in at least one of the transport front-rear direction Yt and the transport left-right direction Xt. Therefore, as an example, the control unit C can match the travel front-rear direction Yr and the transport front-rear direction Yt until the maximum pendulum motion can be generated, and the control of the pendulum mechanism 14 can be simplified. Furthermore, the autonomous mobile robot R can reduce the frequency of rotation of the pendulum mechanism 14 and the top plate 111 by the rotation mechanism 13, and can reduce unnecessary rotation of the object placed on the top plate 111 and the transport unit 1.

[0077] When the calculated acceleration of the autonomous traveling robot R exceeds a threshold value, the control unit C (rotation ECU 133) controls the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the transport front-rear direction Yt and the transport left-right direction Xt are inclined with respect to the traveling direction (travel front-rear direction Yr) of the traveling unit 2. Therefore, as an example, the pendulum mechanism 14 can distribute the direction of pendulum motion to the transport front-rear direction Yt and the transport left-right direction Xt. Therefore, the pendulum mechanism 14 can absorb larger vibrations, swings, centrifugal forces, and other forces acting on an object placed on the top board 111.

[0078] When the calculated acceleration of the autonomous traveling robot R exceeds a threshold value, the control unit C (rotation ECU 133) rotates the pendulum mechanism 14 of the rotation mechanism 13 so that the center of the front face 15 of the transport unit 1 is shifted about the axis Z relative to the center of the front face 23 of the traveling unit 2. Thus, as an example, the pendulum mechanism 14 can distribute the direction of the pendulum motion to the transport front-rear direction Yt and the transport left-right direction Xt. Therefore, the pendulum mechanism 14 can absorb larger vibrations, swings, centrifugal forces, and other forces acting on an object placed on the top board 111.

[0079] The program executed by the control unit C of the autonomous mobile robot R of this embodiment can be provided by recording it in an installable or executable file format on a recording medium readable by a computer device, such as a CD (Compact Disc)-ROM (Read Only Memory), a flexible disk (FD), a CD-R (Recordable), or a DVD (Digital Versatile Disk). The program may also be provided or distributed via a network such as the Internet.

[0080] Second embodiment The second embodiment will be described below with reference to Fig. 6. In the following description of the embodiment, components having the same functions as components already described are given the same reference numerals as the components already described, and further description may be omitted. In addition, multiple components given the same reference numerals do not necessarily have all the same functions and properties, and may have different functions and properties according to each embodiment.

[0081] Fig. 6 is a plan view showing an oblique orientation of the autonomous traveling robot R of the second embodiment. As shown in Fig. 6, the traveling unit 2 of the second embodiment can turn the axle of the drive wheel 21. Therefore, in the second embodiment, the traveling direction of the traveling unit 2 may be oblique to the traveling front-rear direction Yr.

[0082] The traveling front-rear direction Yr in the second embodiment is, for example, a direction that is pre-recorded in the memory of the rotation ECU 133 as the front-rear direction of the traveling unit 2 and the autonomous traveling robot R. In addition, the traveling front-rear direction Yr is also a direction that can be normally recognized as the front-rear direction of the traveling unit 2 and the autonomous traveling robot R.

[0083] When the rotation ECU 133 of the second embodiment causes the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the pendulum mechanism 14 is in an oblique state, the transport longitudinal direction Yt and the transport lateral direction Xt become oblique with respect to the traveling direction of the traveling unit 2. In other words, when the traveling direction of the traveling unit 2 is shifted by approximately 45° around the axis Z with respect to the traveling longitudinal direction Yr, the rotation ECU 133 causes the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the transport longitudinal direction Yt is shifted by an angle other than 45° around the axis Z with respect to the traveling longitudinal direction Yr.

[0084] In the autonomous traveling robot R of the second embodiment described above, when the calculated acceleration of the autonomous traveling robot R exceeds a threshold value, the control unit C (rotation ECU 133) controls the rotation mechanism 13 to rotate the pendulum mechanism 14 so that the transport front-rear direction Yt and the transport left-right direction Xt are oblique to the traveling direction of the traveling unit 2. Therefore, as an example, the pendulum mechanism 14 can distribute the direction of pendulum motion to the transport front-rear direction Yt and the transport left-right direction Xt. Therefore, the pendulum mechanism 14 can absorb larger vibrations, swings, centrifugal forces, and other forces acting on an object placed on the top board 111.

[0085] Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This new embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

[0086] For example, the acceleration sensor 146 may be provided in the traveling unit 2, instead of in the pendulum mechanism 14. In that case, however, the acceleration sensor 146 does not detect the acceleration due to the pendulum motion by the pendulum mechanism 14 or the rotational motion by the rotation mechanism 13. However, the pendulum ECU 147 can determine the control contents for the left / right pendulum drive unit 143 and the front / rear pendulum drive unit 144 by using not only the detection signal by the acceleration sensor 146, but also previous control signals by the pendulum ECU 147 to the left / right pendulum drive unit 143 and the front / rear pendulum drive unit 144, and previous control signals by the rotation ECU 133 to the rotation drive unit 131.

[0087] On the other hand, if the acceleration sensor 146 is provided in the pendulum mechanism 14 as in the above embodiment, such complicated processing is not required because the acceleration sensor 146 detects the acceleration due to the pendulum motion of the pendulum mechanism 14 and the rotational motion of the rotation mechanism 13. In other words, the control contents for the left-right pendulum drive unit 143 and the front-rear pendulum drive unit 144 can be determined by simple processing based only on the detection signal from the acceleration sensor 146.

[0088] Furthermore, the pendulum motion of the pendulum mechanism 14 is not limited to that performed by the actuators of the left-right pendulum drive unit 143 and the front-rear pendulum drive unit 144. The pendulum motion of the pendulum mechanism 14 may be performed by, for example, gravity, inertial force, or centrifugal force acting on the pendulum mechanism 14 or the upper body 11. For example, when the autonomous traveling robot R travels on a slope, the pendulum mechanism 14 may cause the upper body 11 to perform pendulum motion by the weight of the pendulum mechanism 14 and the upper body 11, thereby keeping the upper surface 111a of the top plate 111 approximately horizontal. [Explanation of symbols]

[0089] 1...transport unit, 111...top plate, 111a...top surface, 13...rotation mechanism, 14...pendulum mechanism, 15...front, 2...running unit, 21...drive wheel, 22...chassis, 23...front, R...autonomous running robot, C...control unit, Yr...forward / rearward direction of travel (forward / rearward direction of running unit), Xt...left / right direction of transport (left / right direction of transport unit), Yt...forward / rearward direction of transport (forward / rearward direction of transport unit), Z...axis.

Claims

1. An autonomous moving body, A traveling unit having a driving wheel and a chassis; A transport unit having a top plate, a pendulum mechanism for causing the top plate to perform pendulum motion in the front-back and left-right directions, and a rotation mechanism for rotating the pendulum mechanism around an axis in the up-down direction, the transport unit being disposed on top of the traveling unit; A control unit that calculates the acceleration of the autonomous moving body, and when the calculated acceleration exceeds a threshold value, controls the rotation mechanism to rotate the pendulum mechanism so that the front-rear direction and the left-right direction of the transport unit are inclined with respect to the front-rear direction of the traveling unit; An autonomous moving body comprising:

2. the control unit controls the pendulum mechanism to cause the tabletop to perform pendulum motion so that a direction of a force acting on an object placed on an upper surface of the tabletop approaches a direction perpendicular to the upper surface; The threshold value is the acceleration of the autonomous moving body at which the direction of the force acting on the object becomes perpendicular to the top surface when the pendulum mechanism causes the top plate to oscillate to the maximum extent in at least one of the forward / backward direction and the left / right direction of the transport unit. The autonomous moving body according to claim 1 .

3. The control unit controls the rotation mechanism to rotate the pendulum mechanism so that the forward / backward direction and the left / right direction of the transport unit are inclined with respect to the traveling direction of the traveling unit when the calculated acceleration of the autonomous moving body exceeds the threshold value. The autonomous moving body according to claim 1 .

4. The control unit controls the rotation mechanism to rotate the pendulum mechanism so that the center of the front face of the transport unit shifts around the axis with respect to the center of the front face of the traveling unit when the calculated acceleration of the autonomous moving body exceeds the threshold value. The autonomous moving body according to claim 1 .

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