Moving body and method for controlling moving body

Abstract

The moving body can pass through the door by itself.SOLUTION: A mobile object includes three or more drive wheels that are separately and independently driven and that are capable of moving the mobile object in all directions on a surface with which each of the drive wheels is in contact, a positional relationship acquisition unit that acquires information regarding a positional relationship between each of the three or more drive wheels and a target object, a pivot drive wheel determination unit that determines any one of the drive wheels as a pivot drive wheel on the basis of the positional relationship, and a drive control unit that drives a rotation drive wheel that is a drive wheel other than the pivot drive wheel among the drive wheels around a point based on the pivot drive wheel as a rotation center.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to a mobile object and a method for controlling the mobile object. [Background technology]

[0002] Japan has been facing a declining population since the 1990s due to a declining birthrate and aging population, and it is predicted that Japan's total population will fall below 90 million around 2070. To make up for the labor shortage caused by the declining population, various robots have been researched and developed to perform tasks in place of humans, and now robots that can perform both simple and very complex tasks have appeared.

[0003] Among robots that can replace humans, service robots that perform work indoors, such as in residential environments, need to be able to overcome obstacles such as climbing stairs and steps, and opening and closing doors on their own without human assistance in order to function indoors.

[0004] One method for a robot to pass through a door is to provide a building with an automatic door or a dedicated opening and closing mechanism that allows the robot to open and close the door, and use these mechanisms (see, for example, Patent Document 1).

[0005] Another method for a robot to pass through a door involves, for example, using an end effector (a human hand) to grasp and pull the doorknob, activating a door stopper and creating an area through which the robot can easily pass (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5237735 [Patent Document 2] Japanese Patent Publication No. 2022-124324 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when using automatic doors or dedicated opening and closing mechanisms in which robots open and close doors, as described in Patent Document 1, there is a problem in that the cost of introducing the robots is high because it requires prior modifications to the building.

[0008] Furthermore, the door passing method described in Patent Document 2 has the problem that, because the door stopper is activated by retreating while turning, fine turning movements are required depending on the robot's mechanism, and it takes a long time to pass through the door. Also, if there is little space around the door where the robot can move to activate the door stopper, it may be difficult for the robot to retreat while holding the doorknob and open the door.

[0009] The present invention has been made in consideration of the above-mentioned points, and aims to provide a technology that allows a moving object to pass through a door by itself. [Means for solving the problem]

[0010] One aspect of the present invention is a mobile body comprising three or more drive wheels, each of which is driven independently and capable of moving the mobile body in all directions on the surface with which each drive wheel contacts; a positional relationship acquisition unit that acquires information regarding the positional relationship between each of the three or more drive wheels and a target object; a pivot drive wheel determination unit that determines one of the drive wheels to be a pivot drive wheel based on the positional relationship; and a drive control unit that drives a rotational drive wheel, which is a drive wheel other than the pivot drive wheel, among the drive wheels, with a point based on the pivot drive wheel as the center of rotation.

[0011] In one aspect of the present invention, the pivot drive wheel determination unit determines, as a pivot drive wheel, any drive wheel within an area in a direction of movement of the target object, within an area in which the target object moves.

[0012] In one aspect of the present invention, the pivot drive wheel determination unit determines, as the pivot drive wheel, the drive wheel that is closest to the target object among the three or more drive wheels.

[0013] In one aspect of the present invention, the pivot drive wheel determination unit determines the rotation drive wheel that is closest to the target object as the pivot drive wheel in the second rotation drive as a result of a first rotation drive in which the rotation drive wheel is driven around a point based on the pivot drive wheel as the center of rotation, and the drive control unit drives the drive wheels other than the pivot drive wheel in the second rotation drive among the respective drive wheels around a point based on the pivot drive wheel in the second rotation drive as the center of rotation.

[0014] In one aspect of the present invention, the target object moves in a tangential direction of a surface where each drive wheel contacts, and the pivot drive wheel stops the movement of the target object by contacting the target object.

[0015] In one aspect of the present invention, the pivot drive wheel moves in the direction of the target object between the start and end of rotational drive that drives the rotational drive wheel around a point based on the pivot drive wheel as a rotation center.

[0016] In one aspect of the present invention, the positional relationship acquisition unit acquires the results of measuring the external force acting on the drive motor that drives the drive wheel, and the pivot drive wheel determination unit determines the drive wheel driven by the drive motor that is subjected to an external force equal to or greater than a threshold value as the pivot drive wheel.

[0017] In addition, in one aspect of the present invention, a portion of the outline of a vehicle section in a plan view that is equipped with respective drive wheels and that can move the moving body has a shape that is concave from the circumference of a circle connecting each drive wheel with the central axis of the moving body as the center point, in the direction of the center point.

[0018] In one aspect of the present invention, the target object is a door that is wide enough to pinch a part of the moving object and is equipped with a door closer.

[0019] Another aspect of the present invention is a method for controlling a moving body, comprising: a positional relationship acquisition process for acquiring information about the positional relationship between each of three or more drive wheels, each of which is driven independently and capable of moving the moving body in all directions on the surface with which each drive wheel contacts, and a target object; a pivot drive wheel determination process for determining one of the drive wheels as a pivot drive wheel based on the positional relationship; and a drive control process for driving a rotational drive wheel, which is a drive wheel other than the pivot drive wheel, among the drive wheels, with a point based on the pivot drive wheel as the center of rotation. [Effects of the Invention]

[0020] According to the present invention, a mobile object can pass through the door by itself. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating an example of a basic configuration of a moving body according to an embodiment. [Figure 2] 1 is a diagram illustrating an example of a basic configuration of a vehicle section according to an embodiment. FIG. [Figure 3] FIG. 2 is a simplified plan view illustrating an example of the shape of a vehicle portion according to the embodiment. [Figure 4] FIG. 2 is a diagram illustrating an example of a basic configuration of a drive unit according to an embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example in which a force sensor is used as a proximity sensor. [Figure 6] FIG. 1 is a diagram for explaining a general translational motion performed by a moving body. [Figure 7] FIG. 1 is a diagram for explaining a general turning motion performed by a moving body. [Figure 8] FIG. 10 is a diagram for explaining a case where a moving body moves straight while performing translational motion. [Figure 9]FIG. 1 is a schematic diagram for explaining an example of a cycloid running method according to an embodiment. [Figure 10] FIG. 10 is a diagram for explaining a rotation center point. [Figure 11] FIG. 10 is a diagram for explaining an example of a door according to an embodiment. [Figure 12] 10A and 10B are diagrams illustrating an example in which the degree of opening of the door is increased by the moving body pressing against the vehicle portion. [Figure 13] FIG. 10 is a plan view illustrating an example of passing through a door using a cycloidal running method. [Figure 14] 10A and 10B are diagrams illustrating an example in which the degree of opening of the door is increased by the moving body pressing against the vehicle portion. [Figure 15] FIG. 10 is a diagram for explaining an example of a modified cycloid running method according to the embodiment. [Figure 16] FIG. 2 is a block diagram illustrating an example of a functional configuration of a control device according to an embodiment. [Figure 17] 10 is a flowchart illustrating an example of a processing flow of a control device according to the embodiment. [Figure 18] FIG. 10 is a simplified plan view illustrating a modified example of the shape of the vehicle portion. [Figure 19] FIG. 2 is a block diagram showing an example of an internal configuration of a control device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] [Embodiment] A preferred embodiment of a moving body and a method for controlling a moving body according to the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, identical or similar parts are designated by identical or similar reference numerals. Note that the present invention is not limited to these embodiments and includes various modifications or improvements. In other words, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical, and the components described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components of the present invention may be made without departing from the spirit and scope of the present invention.

[0023] First, an overview of the moving object 1 will be described with reference to Fig. 1. In the embodiment, a case where the moving object 1 passes through a door equipped with a door closer and opening toward the moving object 1 will be described as an example. In the following description, an object that becomes an obstacle to the movement of the moving object 1, such as a door, may be referred to as a target object.

[0024] 1 is a diagram illustrating an example of the basic configuration of a moving body 1 according to an embodiment. The moving body 1 includes an end effector 100, a manipulator 200, and a vehicle unit 300. The end effector 100 is attached to the manipulator 200. The vehicle unit 300 supports and moves the end effector 100 and the manipulator 200.

[0025] The end effector 100 plays the role of a human hand. The end effector 100 grips a doorknob. Specifically, the end effector 100 may include a first part that moves in a first direction and a second part (human finger) that moves parallel to the first direction and in the opposite direction to grip and turn a lever-type rod-shaped doorknob. When the end effector 100 approaches the doorknob to within a distance of about 50 mm, it grips the doorknob using the first part and the second part so as to cover it. Note that the end effector 100 may include a hook with a curved tip that can hook onto the doorknob, instead of the first part and the second part.

[0026] The manipulator 200 plays the role of a human arm. The manipulator 200 drives the end effector 100 three-dimensionally. The manipulator 200 according to the embodiment has a SCARA mechanism. The SCARA manipulator 200 can efficiently remove the latch of a door by moving a lever-type doorknob downwards without twisting it.

[0027] The vehicle section 300 plays the role of a human's legs. The vehicle section 300 can move the moving object 1 in all directions parallel to the horizontal plane. A brief overview of the vehicle section 300 will be given with reference to FIG.

[0028] FIG. 2 is a diagram illustrating an example of the basic configuration of the vehicle unit 300 according to the embodiment. The vehicle unit 300 includes a first drive unit 310, a second drive unit 320, a third drive unit 330, and a vehicle body main body 340. The first drive unit 310 to the third drive unit 330 are driven independently. In the embodiment, the first drive unit 310, the second drive unit 320, and the third drive unit 330 are arranged with their directions shifted by 120° from one another, based on a vehicle center point O, which is the central axis of the vehicle. The vehicle center point O is a point on the axis of rotation when the vehicle 1 is driven to turn. Note that the vehicle unit 300 according to the embodiment does not necessarily have to include three drive units. For example, the vehicle unit 300 may include four or more drive units. The drive units may be arranged so that the angular difference between the directions of the drive units is equal, based on the vehicle center point O. Each of the first drive unit 310 to the third drive unit 330 is connected to the vehicle body 340. Note that each drive wheel and the vehicle body 340 may be configured separately and independently, or each drive wheel and the vehicle body 340 may be configured as a single member. When each drive wheel and the vehicle body 340 are configured as a single member, for example, the portion of the vehicle unit 300 that is connected to the manipulator 200 may be the vehicle body 340.

[0029] FIG. 3 is a simplified plan view illustrating an example of the shape of vehicle unit 300 according to the embodiment. In a plan view (viewed from above), a portion of the contour of vehicle unit 300 has a shape that is recessed in a direction toward vehicle center point O from the circumference of a circle connecting each drive wheel of vehicle 1 with vehicle center point O as the center. In other words, the contour shape of vehicle unit 300 in a plan view is not circular. Because the contour of vehicle unit 300 in a plan view is recessed, vehicle unit 300 has object-free areas between first drive unit 310 and second drive unit 320, between second drive unit 320 and third drive unit 330, and between third drive unit 330 and first drive unit 310. When a target object comes into contact with the drive unit of rotating vehicle 1, the target object enters the object-free area and gets caught on the drive unit. Therefore, vehicle unit 300 having a recessed shape can more easily apply force to the target object than a circular vehicle unit.

[0030] 4 is a diagram illustrating an example of the basic configuration of a drive unit according to an embodiment. The first drive unit 310 includes a drive wheel 311, a drive motor 312, a fender 313, an x-direction leaf spring 314, and a y-direction leaf spring 315. Although not shown, the first drive unit 310 may also include a circuit for detecting the rotational speed of the drive wheel 311. Note that the second drive unit 320 and the third drive unit 330 have the same configuration as the first drive unit 310, and therefore their description will be omitted. Hereinafter, the components of the second drive unit 320 and the third drive unit 330 may be described using the same reference numerals as those of the first drive unit 310.

[0031] An example of the drive wheel 311, which is an omniwheel, is shown in Figure 4. Each drive wheel provided on each drive unit can be driven independently, allowing the mobile object 1 to move in all directions on the surface with which each drive wheel is in contact. The drive wheel 311 has multiple wheels arranged around the periphery of the wheel that rotate in a direction perpendicular to the rotation direction of the wheel body, allowing the mobile object 1 to move in all directions.

[0032] The drive motor 312 generates torque to drive the drive wheels 311. The drive motor 312 may include a function of a reducer, and increases the torque by slowing down the rotation, and transmits the rotational force to the drive wheels 311.

[0033] The fender 313 protects the drive wheels 311 from direct contact with an object. The fender 313 may be, for example, a cover provided on the movable body 1. A portion of the fender 313 is located outside a circle connecting each of the drive wheels, centered on the movable body center point O of the movable body 1, and is rigidly connected to the drive motor 312 so that its position relative to the drive motor 312 does not change. The fender 313 may be attached to any part of the first drive unit 310, such as the drive motor 312 or an x-direction leaf spring 314 (described later). FIG. 4 shows an example in which the fenders 313 are provided on the left and right sides of the drive wheels 311, but this embodiment is not limited to this example and may also be provided above the drive wheels 311. Attaching the fenders 313 to the drive unit prevents the drive wheels 311 from contacting the door and soiling the door.

[0034] FIG. 5 is a diagram illustrating an example of using a force sensor as a proximity sensor. Referring to FIG. 5, the x-direction leaf spring 314 and the y-direction leaf spring 315, which are proximity sensors attached to the drive motor 312, will be described. A proximity sensor is a sensor that detects whether a target object and the moving body 1 are in proximity, i.e., whether they are in contact or approaching each other. The proximity sensor may be, for example, a force sensor that measures an external force received by the drive motor 312 and detects contact; a sensor that measures the distance to the target object and detects proximity, such as an ultrasonic sensor, an infrared distance sensor, or a laser distance sensor; or a sensor that captures an image of the vicinity of the first drive unit 310 and detects proximity between the first drive unit 310 and the target object from the captured image. FIG. 5 illustrates an example of using a leaf spring, a structural member that deforms when subjected to an external force, as a force sensor.

[0035] The x-direction leaf springs 314 are attached to the drive motor 312 perpendicular to the contact surface of each drive wheel. The x-direction leaf springs 314 deform due to an external force applied to the axle of the drive motor 312, and are used to measure the magnitude and direction of a disturbance in a direction parallel to the contact surface (hereinafter sometimes referred to as the x-direction). The results measured using the x-direction leaf springs 314 may be used for control, for example, depending on whether or not the vehicle is close to a target object.

[0036] The y-direction leaf spring 315 is attached to the drive motor 312 parallel to the contact surface. The y-direction leaf spring 315 deforms due to an external force applied to the axle of the drive motor 312, and is used to measure the magnitude and direction of a disturbance in a direction perpendicular to the contact surface (hereinafter sometimes referred to as the y direction). The results measured using the y-direction leaf spring 315 may be used, for example, for controlling the attitude of the moving body 1 or for detecting small irregularities on the contact surface.

[0037] By employing the x-direction leaf spring 314 and the y-direction leaf spring 315 as proximity sensors, the movable body 1 can suppress the impact transmitted to the drive motor 312. Furthermore, the movable body 1 may employ the x-direction leaf spring 314 and the y-direction leaf spring 315, which are more flexible, in order to further suppress the impact transmitted to the drive motor 312. Note that FIG. 5 shows an example in which the x-direction leaf spring 314 and the y-direction leaf spring 315 are not directly connected to each other but are attached to the drive motor 312. However, this embodiment is not limited to this example, and the x-direction leaf spring 314 and the y-direction leaf spring 315 may be connected to each other and attached to the drive motor 312 as a rectangular tube. Note that the leaf springs shown in FIG. 5 are an example of a strain-generating body and are not necessarily limited to leaf springs.

[0038] 6 is a diagram for explaining a general translational motion performed by the moving body 1. The figure shows a top view of the vehicle unit 300. Drive wheels (1) to (3) are drive wheels 311 provided on the first drive unit 310 to the third drive unit 330, respectively.

[0039] 6(A) shows an example in which the moving body 1 is translated from the ground contact center point GOP of the stopped driving wheel (3) toward the moving body center point O by driving the driving wheel (1) counterclockwise relative to the moving body center point O, driving the driving wheel (2) clockwise relative to the moving body center point O, and stopping the driving wheel (3). The ground contact center point GOP is a point that is treated as the center of contact between the driving wheel 311 and the floor. For example, when the wheels (small wheels) arranged on the periphery of the wheels (large wheels) provided on the driving wheel 311 are arranged in double rows so as not to come into discontinuous contact with the floor, the ground contact center point GOP may be a point on the contact surface between the driving wheel 311 and the floor, and may be a point between the inner large wheel and the outer large wheel.

[0040] In the translational motion shown in Figure 6(A), the front wheels, drive wheels (1) and (2), are driven, so they tend to exert a force that causes them to climb up a step (such as a groove in a rail or a slippage). On the other hand, the rear wheel, drive wheel (3), is stopped, so after drive wheels (1) and (2) climb up a step, it may be difficult for drive wheel (3) to climb up the step.

[0041] The translational motion shown in Fig. 6(B) drives drive wheel (1) and drive wheel (2) and stops drive wheel (3), similar to the translational motion shown in Fig. 6(A). In Fig. 6(B), drive wheel (1) drives clockwise based on the center point O of the moving body, and drive wheel (2) drives counterclockwise based on the center point O of the moving body, i.e., by driving in the opposite direction to Fig. 6(A), the moving body 1 performs translational motion from the center point O of the moving body toward the ground contact center point GOP of the drive wheel (3).

[0042] In the translational movement shown in FIG. 6(B), the front drive wheel (3) is stopped and the rotation direction of the drive wheel (3) is parallel to the step, so it may be difficult for the drive wheel (3) to climb up the step.

[0043] The translational motion shown in Fig. 6(C) drives the moving body 1 in any direction by controlling the rotational speed and rotational direction of each of the drive wheels (1) to (3). The translational motion shown in Fig. 6(C) can use three drive wheels, so the driving force of the moving body 1 is the greatest. The translational motion shown in Fig. 6(C) may not generate enough force to climb over the step depending on the angle at which the step and each drive wheel 311 contact. The more perpendicular the step and the rotational direction of the large wheel of the drive wheel 311 are to each other, the more difficult it is to generate a climbing force.

[0044] FIG. 7 is a diagram illustrating a typical turning motion performed by the moving body 1. By driving each of the drive wheels 311 at the same rotation speed, the moving body 1 turns (turns) on the spot, with the moving body's center point O as the center of rotation. During turning motion, cooperation between the drive wheels 311 can be disrupted by external forces (for example, a force being pushed by a target object) received by the moving body 1, making it difficult for the moving body 1 to operate as intended. Furthermore, when turning motion is used to push a target object, the moment arm MA (the distance from the moving body's center point O, which is the center of rotation, to the ground contact center point GOP of each drive wheel) is shorter compared to the case of cycloidal running, which will be described later, and therefore the driving force borne by each drive wheel 311 can be large.

[0045] FIG. 8 is a diagram illustrating a case where the moving object 1 moves straight while moving in a translational motion. In FIG. 8, each drive wheel 311 rotates around the moving object center point O as the center of rotation, and is driven so that the entire moving object 1 moves in a fixed direction. In this case, the contact center point GOP of each drive wheel 311 with the floor traces a cycloidal locus. When performing the movement shown in FIG. 8, each drive wheel 311 can contact the step at an angle close to a right angle, and a force to climb up the step is easily generated. Therefore, the movement shown in FIG. 8 makes it easier for the drive wheels 311 to climb over steps that are generally difficult for the moving object 1 to climb. Note that when performing the movement shown in FIG. 8, by orthogonally orthogonally orienting the moving direction of the moving object 1 and the step, the moving object 1 can more easily climb over the step.

[0046] 9 is a diagram illustrating cycloid running according to an embodiment. Cycloid running is a movement in which the rotation center point COR is moved from the moving object center point O (movement in FIG. 8) in the direction of the ground contact center point GOP of one of the drive wheels 311. Specifically, in the case of cycloid running according to this embodiment, drive wheel (1) stops driving, and drive wheels (2) and (3) synchronize their rotational speeds and drive in the same direction (counterclockwise in the case of FIG. 9), causing the moving object 1 to rotate around the ground contact center point GOP of drive wheel (1) as the rotation center point COR.

[0047] FIG. 10 is a diagram illustrating the rotation center point COR. In FIG. 10, the drive wheel (1) is stationary. The rotation center point COR is the point that serves as the center of rotation when the vehicle 1 performs cycloid running. The rotation center point COR is determined based on the drive wheel that serves as the center of rotation. Specifically, the rotation center point COR may be a point located within the drive wheel (drive wheel (1)) that serves as the center of rotation or a cover that protects the drive wheel on the contact surface between each drive wheel 311 and the floor, within the region (first region A1 and second region A2) located in the direction of the drive wheel (1) relative to the vehicle center point O. Furthermore, the rotation center point COR may be located within the region (second region A2) outside the vehicle body 340 within the above-mentioned regions in order to lengthen the moment arm MA. The rotation center point COR is preferably located within a region outside the vehicle body 340. The rotation center point COR may be, for example, the ground contact center point GOP of the drive wheel 311 that serves as the center of rotation. When the ground contact center GOP of the drive wheel 311 that is the center of rotation is set as the rotation center point COR, each of the drive wheels 311 that are not the center of rotation can be driven at the same rotation speed, simplifying drive control. In the following description, the drive wheel that is the center of rotation will be referred to as the pivot drive wheel, and the drive wheels other than the pivot drive wheel among drive wheels (1) to (3) will sometimes be referred to as the rotation drive wheels. Note that the pivot drive wheels do not necessarily need to be stopped, and may be driven if the rotation center point COR is set at a point other than the ground contact center GOP of the pivot drive wheel.

[0048] When cycloidal running is used to push an object, the moment arm (for example, the distance from the rotation center point COR to the ground contact center point GOP of the rotation drive wheel) is longer than in turning motion, so the driving force borne by each drive wheel 311 is smaller. Also, cycloidal running makes it easier to overcome steps, just like when the moving body 1 moves straight while moving in a translational motion.

[0049] After performing cycloidal running with drive wheel (1) as the pivot drive wheel, vehicle unit 300 may perform cycloidal running again in the same rotational direction (counterclockwise in the case of Figure 9) with one of the rotational drive wheels (drive wheel (2) or drive wheel (3)) as the pivot drive wheel. In other words, vehicle unit 300 may repeat cycloidal running while switching the pivot drive wheel. Note that the cycloidal running before switching the pivot drive wheel may be referred to as the first cycloidal running, and the cycloidal running after switching the pivot drive wheel may be referred to as the second cycloidal running. Also, cycloidal running may be simply referred to as rotational driving.

[0050] FIG. 11 is a diagram for explaining an example of the door TO according to the embodiment. The door TO shown in FIG. 11 is an example of a target object. FIG. 11 shows a case where the door TO is a hinged door equipped with a door closer and is already open. The door closer automatically closes the door TO by applying a closing force to the door TO. In FIG. 11, the door TO rotates counterclockwise around the hinge H as viewed from above the door TO and closes due to the closing force of the door closer. At this time, the door TO opens and closes in the tangential direction of the contact surface (floor surface) with which each drive wheel 311 comes into contact, i.e., along the contact surface. Hereinafter, the surface on the moving direction side of the door TO, which is the target object, may be referred to as the inside, the side opposite to the moving direction of the door TO as the outside, the hinge side of the door TO as the back side, and the latch side of the door TO as the front side.

[0051] When the opening angle of the door TO is small, the closing force (moment) of the door closer is small and the door TO moves slowly. When the opening angle of the door TO is small, the opening force required is small, so the moving body 1 can easily open the door TO using the end effector 100 and the manipulator 200.

[0052] When the door TO is opened to a medium degree, the closing force of the door closer is large and the door TO moves quickly. When the door TO is opened to a large degree, the opening force required is large, so it may be difficult for the moving body 1 to open the door TO using only the end effector 100 and the manipulator 200. In this case, the moving body 1 needs to devise a way to open the door TO. Specifically, the moving body 1 may pull the door TO more strongly by driving the vehicle part 300 while the end effector 100 pulls the door TO. Also, the moving body 1 may drive the vehicle part 300 so that it comes into contact with the door TO and pushes the door TO in the opening direction.

[0053] When the opening angle of the door TO is equal to or greater than a certain value, the door stopper operates and the door TO does not close. In this case, the moving body 1 does not need to apply an opening force to the door TO.

[0054] The door TO being open refers to, for example, a case where the distance from the door latch (bolt) of the door TO to the trowel holder that stores the door latch is equal to or greater than the width of a part of the moving body. The part of the moving body is, for example, a cover that protects the moving body 1 or the drive wheel 311, which is a part that can pinch and prevent the door TO from closing. The door TO may be opened by the moving body 1 using the end effector 100, manipulator 200, and vehicle unit 300, or may be opened by a person who notices the approach of the moving body 1 or by a mechanism (not shown).

[0055] FIG. 12 is a diagram illustrating an example in which the moving object 1 increases the opening degree of the door TO by pushing the vehicle section 300 against it. Depending on the opening degree of the door TO, when the moving object 1 performs cycloidal travel, it may collide with a wall W, making it difficult for the moving object 1 to pass through the door TO. Therefore, the moving object 1 increases the opening degree of the door TO before performing cycloidal travel. Specifically, the moving object 1 shown in FIG. 12 prevents the door TO from closing by bringing the drive wheel (1) into contact with the door TO. However, because the drive wheel (3) is in contact with the wall, the moving object 1 cannot pass through the door TO as it is. Therefore, the moving object 1 increases the opening degree of the door TO by pushing the door TO in the direction opposite to the movement direction of the door TO (from the inside to the outside of the door TO), thereby ensuring a width that allows the moving object 1 to pass through the door TO. 12 shows an example in which the moving body 1 performs cycloidal running by driving the driving wheels (1) and (3) counterclockwise at the same rotational speed, with the ground contact center GOP of the driving wheel (2) as the rotation center COR. When cycloidal running is used to increase the opening degree of the door TO, the moving distance of the center of gravity of the moving body 1 is shorter compared to translational running, which reduces the inertial force acting on the moving body 1 and makes it less likely for the moving body 1 to lose its posture. Furthermore, since the moment arm MA is longer in cycloidal running compared to rotational running, the force required for the moving body 1 to increase the opening degree of the door TO can be reduced.

[0056] FIG. 13 is a plan view illustrating an example of passing through a door TO, which is a target object, using a cycloidal travel method. FIG. 13(A) is a diagram illustrating an example of a case where the target object comes into contact with the vehicle unit 300. The vehicle unit 300 may approach the door TO, for example, using a cycloidal travel method in the same rotational direction as the door TO, i.e., counterclockwise. This brings the drive wheel (1) close to the inside of the door TO. The vehicle unit 300 may also increase the opening degree of the door TO by pushing the door TO from the inside to the outside of the door TO.

[0057] FIG. 13(B) shows an example of a state after the door TO and the vehicle unit 300 come into contact, depicting a scene later in time than FIG. 13(A). The vehicle unit 300 uses the contacted drive wheel (1) as a pivot drive wheel, and the other drive wheels (2) and (3) as rotary drive wheels. The vehicle unit 300 performs counterclockwise cycloidal running by driving the drive wheels (2) and (3) counterclockwise, which is the same rotation direction as when approaching the door TO, with a point based on the drive wheel (1) as the rotation center point COR. This allows the moving body 1 to move in a direction passing through the door TO while the drive wheel (1), which is the pivot drive wheel, prevents the door TO from moving, i.e., preventing the door TO from closing. Furthermore, by using the pivot drive wheel to stop the door TO, the cooperation of the rotary drive wheels is not disrupted by the closing force of the door TO, simplifying the drive control of each drive wheel 311. When the drive wheel 311 adjacent to the inside of the door TO is determined to be the pivot drive wheel, the cycloidal running method starts.

[0058] Fig. 13(C) is a diagram showing an example of the timing for performing the second rotation drive, and shows a scene later in time than Fig. 13(B). In Fig. 13(C), the vehicle unit 300 performs the first rotation drive using the drive wheel (1) approaching the door TO as the pivot drive wheel, so that one of the rotation drive wheels (drive wheel (3) in Fig. 13) approaches the door TO. The drive wheel (3), which is the rotation drive wheel approaching the door TO, is determined to be the new pivot drive wheel. Accordingly, the drive wheels other than the drive wheel (3) (drive wheel (1) and drive wheel (2)), including the drive wheel (1) that was the pivot drive wheel in the first rotation drive, are determined to be rotation drive wheels. The vehicle unit 300 switches the pivot drive wheel to drive wheel (3) and performs a second rotational drive in the counterclockwise direction, which is the same as the rotational direction in the first rotational drive. For example, the vehicle unit 300 stops drive wheel (3), which is the pivot drive wheel, and drives drive wheels (1) and (2) around the ground contact center GOP of drive wheel (3) in the same rotational direction (counterclockwise) as the first rotational drive, with the rotational speed synchronized. When either drive wheel (2) or drive wheel (3), which is the drive wheel 311 other than the pivot drive wheel in the first rotational drive, approaches the inside of the door TO and the drive wheel 311 is determined to be the pivot drive wheel in the second rotational drive, the cycloidal running ends. By repeatedly performing the cycloidal running, the mobile unit 1 can pass through the door TO while the movement of the door TO is stopped by either drive wheel determined to be the pivot drive wheel. Note that in the embodiment, it is not necessarily required for the vehicle unit 300 to repeat the cycloidal running. Depending on the positional relationship between the door TO and the moving body 1, the vehicle section 300 may perform translational motion in the direction of passing through the door TO.

[0059] FIG. 14 is a diagram for explaining an example in which a drive wheel 311 is close to the door TO. The drive wheel 311 close to the door TO is, for example, the drive wheel 311 closest to the inside of the door TO. Furthermore, the drive wheel 311 close to the door TO is, for example, one of the drive wheels 311 that are partially within the area (fourth area A4) on the movement direction side of the door TO among the areas (third area A3 and fourth area A4) in which the door TO can move. The area in which the door TO can move is, for example, the movable range of the door TO, which is a substantially sector-shaped area centered on the hinge H. The movement direction of the door TO is the direction in which the door TO itself moves when no force is applied from the movable body 1, and is the direction from the outside to the inside of the door TO. When there are multiple drive wheels 311 in the fourth area A4, the drive wheel 311 close to the door TO may be, for example, any drive wheel 311 in the first area A1, or the drive wheel 311 closest to the inside of the door TO in the first area A1.

[0060] 15 is a diagram for explaining an example of modified cycloidal running according to the embodiment. The modified cycloidal running, which is a variation of the cycloidal running, will be specifically explained with reference to the same figure. The modified cycloidal running is a running method in which the door TO and the pivot drive wheel do not release contact from the start to the end of the cycloidal running.

[0061] 15(A) is a diagram showing an example of when the contact between the door TO and the drive wheel (1) is released. When the drive wheel (1) comes into contact with the front side (bar side) of the door TO, the contact position between the drive unit including the drive wheel (1) and the door TO changes during the cycloidal travel with the drive wheel (1) as the pivot drive wheel, which may cause the contact to be released and the door TO to close. Also, when the door TO is rotated to increase its opening, after the rotation and release of contact with the door TO, the door TO may close without coming into contact with any drive unit.

[0062] 15(B) is a diagram showing an example of a modified cycloidal running method that does not release contact. Between the start and end of the cycloidal running method in which the drive wheel (1) serves as the pivot drive wheel, the vehicle unit 300 moves from the pivot drive wheel in the direction of the door TO, thereby increasing the opening degree of the door TO and moving toward the back of the door TO to maintain contact. Note that in the modified cycloidal running method, the vehicle unit 300 may move in parallel during the cycloidal running method, or the vehicle unit 300 as a whole may move from the pivot drive wheel in the direction of the door TO while performing the cycloidal running method.

[0063] FIG. 16 is a block diagram illustrating an example of the functional configuration of the control device 400 according to an embodiment. The control device 400 acquires information from the vehicle unit 300 of the moving object 1 and controls the drive of the vehicle unit 300. The control device 400 has functions for implementing the cycloidal running method and the modified cycloidal running method described above. Specifically, the control device 400 includes a positional relationship acquisition unit 410, a pivot drive wheel determination unit 420, and a drive control unit 430. Each of these functional units is implemented using, for example, a computer including a CPU (Central Processing Unit) and memory, and software. Each functional unit may also be implemented using electronic circuits as necessary. Furthermore, each functional unit does not have to be included in a single device, and the control device 400 may be configured from multiple devices.

[0064] The control device 400 may be provided in the mobile object 1, or may be provided separately from the mobile object 1 and connected via a network. The network NW is a predetermined communication network configured using lines. An example of the network NW is the Internet. The predetermined communication network is an open network, and devices connected to the communication network can communicate with each other using a predetermined protocol. In the Internet layer of the communication network, communication is performed using the Internet Protocol (IP) or the like. For example, wireless, Wi-Fi (registered trademark), or Bluetooth (registered trademark) may be used in the network NW.

[0065] The positional relationship acquisition unit 410 acquires information regarding the positional relationship between the door TO and each drive wheel 311 from a proximity sensor or a processing device (not shown) that processes the results measured by the proximity sensor. The positional relationship may be, for example, information indicating the door TO and each drive wheel 311, information indicating a drive wheel 311 close to the door TO, or information indicating the relative position of each drive wheel 311 with respect to the door TO. In this embodiment, the positional relationship acquisition unit 410 acquires information indicating the magnitude of an external force in the x direction from the door TO to the drive motor 312. The information indicating the magnitude of the external force may be, for example, a current value corresponding to the degree of distortion of the leaf spring.

[0066] The pivot drive wheel determination unit 420 identifies the drive wheels 311 that are close to the door TO based on the information on the positional relationship acquired by the positional relationship acquisition unit 410, and determines the identified drive wheels 311 as pivot drive wheels. Specifically, the pivot drive wheel determination unit 420 may determine, as pivot drive wheels, drive wheels 311 that are close to the door TO by a predetermined distance or more (e.g., 1 cm) from the inside of the door TO. Drive wheels 311 that are close by a predetermined distance or more are, for example, drive wheels 311 that are in a position that will soon come into contact with the door TO or that are already in contact with the door TO. Furthermore, the pivot drive wheel determination unit 420 may determine, as pivot drive wheels, any drive wheels 311 that are located within the fourth area A4 and on the inside of the door TO. In this embodiment, the pivot drive wheel determination unit 420 determines, as pivot drive wheels, drive wheels 311 driven by drive motors 312 that generate an external force in the x direction that is equal to or greater than a predetermined threshold. The threshold value may be determined based on the magnitude of the external force measured when the door TO comes into contact with the drive unit.

[0067] Furthermore, if the magnitude of the external force in the x direction on any of the rotational drive wheels becomes equal to or greater than a threshold value as a result of performing the cycloid running method, the pivot drive wheel determination unit 420 determines that rotational drive wheel as the pivot drive wheel in the second rotational drive. Note that the pivot drive wheel in the first rotational drive may also be referred to as the first pivot drive wheel, and the pivot drive wheel in the second rotational drive may also be referred to as the second pivot drive wheel.

[0068] The drive control unit 430 controls the drive motor 312 to drive the other drive wheels 311, that is, the rotation drive wheels, in the same rotation direction and at the same rotation speed, with the rotation center point COR (e.g., the ground contact center point GOP of the pivot drive wheel) based on the pivot drive wheel determined by the pivot drive wheel determination unit 420 as the center of rotation.

[0069] Furthermore, the drive control unit 430 may control the drive motor 312 to move the pivot drive wheel toward the door TO at a predetermined timing. The predetermined timing may be when the contact between the door TO and the pivot drive wheel is released, or when a predetermined time has elapsed since the cycloidal travel method was performed.

[0070] The drive motors 312 rotate the drive wheels 311 under the control of the drive control unit 430. By controlling each drive motor 312 by the drive control unit 430, the vehicle unit 300 can perform cycloid running or modified cycloid running.

[0071] 17 is a flowchart illustrating an example of the processing flow of the control device 400 according to the embodiment. With reference to the same figure, an example of processing for realizing the cycloid running style will be described.

[0072] (Step S101) The control device 400 acquires information indicating the external force acting on a drive unit (for example, the fender 313) as information related to the positional relationship. If the external force does not reach or exceed the threshold for any of the drive units, the control device 400 continues to acquire information indicating the external force acting on the drive units in order to determine the pivot drive wheel. That is, the control device 400 monitors whether the external force acting on the drive unit reaches or exceeds the threshold.

[0073] (Step S102) The control device 400 determines the drive wheel 311 provided in the drive unit to which the external force equal to or greater than the threshold value has been applied as the first pivot drive wheel. The control device 400 also determines the drive wheels 311 other than the first pivot drive wheel, among the drive wheels 311 provided in the first drive unit 310 to the third drive unit 330, as the rotation drive wheels.

[0074] (Step S103) Control device 400 controls each rotation drive wheel to rotate at a synchronized rotational speed around rotation center point COR based on the first pivot drive wheel. That is, control device 400 controls vehicle unit 300 to perform the first rotation drive.

[0075] (Step S104) Control device 400 acquires information indicating the external force acting on the rotation drive wheels. If the external force is not equal to or greater than the threshold for any of the rotation drive units, control device 400 continues to control vehicle unit 300 to perform the first rotation drive.

[0076] (Step S105) When an external force equal to or greater than a threshold is applied to a drive unit equipped with a rotation drive wheel, the control device 400 determines the rotation drive wheel equipped in the drive unit to which the external force equal to or greater than the threshold is applied as the second pivot drive wheel. Furthermore, the control device 400 determines the drive wheel 311 other than the second pivot drive wheel among the drive wheels 311 equipped in each of the first drive unit 310 to the third drive unit 330 as the rotation drive wheel. In other words, the control device 400 switches the rotation drive wheel adjacent to the door TO to the next pivot drive wheel.

[0077] (Step S106) The control device 400 controls the rotational drive wheels so that their rotational speeds are synchronized around the rotation center point COR based on the second pivot drive wheel. That is, the control device 400 controls the vehicle unit 300 to perform the second rotational drive. Note that the control device 400 may also switch the pivot drive wheels as needed to perform the third and subsequent cycloidal running methods.

[0078] FIG. 18 is a simplified plan view for explaining a modified shape of the vehicle unit 300. In the above, an example in which the vehicle unit 300 has three wheels has been described. However, this embodiment is not limited to this example, and may have, for example, four or more wheels. FIG. 18(A) shows an example in which the vehicle unit 300A has four drive units. The drive units are arranged so that their directions differ by 90° from each other. In other words, the drive units are arranged so that the angular difference between the directions of the drive units is equal, with the moving body center point O as the reference.

[0079] In the above description, an example is shown in which the vehicle unit 300 is provided with a cover that fits along the drive unit. However, this embodiment is not limited to this example, and the cover does not need to fit along the drive unit. FIG. 18(B) shows an example in which the cover provided on the vehicle unit 300B has a protrusion. By providing the protrusion on the cover, the movable body 1 can hook the protrusion on the door TO when widening the opening of the door TO.

[0080] It is desirable that the cover according to this embodiment have a low friction force between the door TO and the cover to prevent the door TO from being scratched or soiled when it comes into contact with the door TO. To reduce the coefficient of friction, the cover may use a material with a low coefficient of friction at the portion where it comes into contact with the door TO. Also, to reduce the coefficient of friction, the cover may be provided with a part (e.g., a roller) that converts sliding friction into rolling friction at the portion where it comes into contact with the door TO.

[0081] In the above description, the drive wheels 311 are omni-wheels. However, this embodiment is not limited to this example, and the drive wheels 311 may be Mecanum wheels. When the drive wheels 311 are Mecanum wheels, the same effect as that of an omni-wheel can be obtained by changing the orientation of each drive wheel 311.

[0082] [Summary of the embodiment] According to the embodiment described above, the mobile object 1 includes three or more drive wheels 311, each of which is independently driven and capable of moving the mobile object 1 in all directions on a surface with which the drive wheels 311 are in contact; a positional relationship acquisition unit 410 that acquires information about the positional relationship between each of the three or more drive wheels 311 and a target object; a pivot drive wheel determination unit 420 that determines one of the drive wheels 311 as a pivot drive wheel based on the positional relationship; and a drive control unit 430 that drives the rotation drive wheels of the drive wheels 311 other than the pivot drive wheel, using a point based on the pivot drive wheel (rotation center point COR) as the center of rotation. That is, the mobile object 1 according to the embodiment performs a cycloidal running technique, with the drive wheel 311 closest to the target object (door TO) as the pivot drive wheel. By stopping the drive of the pivot drive wheel closest to the target object, the mobile object 1 can move along the target object while stopping the movement of the target object. This allows the moving body 1 to easily pass through the door TO, which would otherwise be an obstacle to the robot's indoor activities.

[0083] Furthermore, since the moving object 1 according to the embodiment passes through the door TO using a cycloidal running method, it is not necessary to activate the door stopper. Therefore, the moving object 1 can pass through the door TO even if there is no area where the robot can retreat while pulling the door handle to activate the door stopper.

[0084] Furthermore, according to the above-described embodiment, the pivot drive wheel determination unit 420 determines, as a pivot drive wheel, any of the drive wheels 311 in the area (fourth area A4) on the movement direction side of the door TO among the areas in which the door TO moves. If a drive wheel 311 not located in the fourth area A4 is determined to be a pivot drive wheel, there is a possibility that the door TO will lose contact with the drive wheel 311 while performing the cycloidal running technique, causing the door TO to close. By stopping the drive of any of the drive wheels 311 located in the fourth area A4 as a pivot drive wheel, the movable body 1 can bring the pivot drive wheel into contact with the door TO and prevent the door TO from closing.

[0085] Furthermore, according to the above-described embodiment, the pivot drive wheel determination unit 420 determines the drive wheel closest to the door TO as the pivot drive wheel among the three or more drive wheels 311. In the cycloidal traveling method, the pivot drive wheel stops driving and comes into contact with the door TO, preventing the door TO from closing. If a drive wheel 311 located far from the door TO is designated as the pivot drive wheel, the door TO may move to the position of the pivot drive wheel, reducing the opening degree of the door TO. By designating the drive wheel 311 located closest to the door TO as the pivot drive wheel, the movement distance of the door TO is shortened, making it easier to ensure the opening degree required for the door TO to pass through.

[0086] Furthermore, according to the above-described embodiment, the pivot drive wheel determination unit 420 determines the rotation drive wheel closest to the target object as the pivot drive wheel for the second rotation drive as a result of the first rotation drive in which the rotation drive wheels are driven around a point based on the first pivot drive wheel (rotation center point COR) as the rotation center, and the drive control unit 430 drives the drive wheels 311 other than the second pivot drive wheel for the second rotation drive among the respective drive wheels around a point based on the second pivot drive wheel for the second rotation drive as the rotation center. In the above-described embodiment, the moving object 1 repeatedly performs a cycloidal running method while switching the pivot drive wheels. Therefore, the moving object 1 can move along the door TO while preventing the door TO from moving. Specifically, the moving object 1 can pass through the door TO while preventing the door TO from closing.

[0087] Furthermore, according to the above-described embodiment, the target object moves in the tangential direction of the surface with which each drive wheel 311 contacts (i.e., in the direction along the floor surface). Furthermore, the pivot drive wheels stop the movement of the target object by contacting the target object. This allows the moving object 1 to pass through the door TO while preventing the door TO from closing, which would be an obstacle to indoor activities.

[0088] Furthermore, according to the above-described embodiment, the pivot drive wheels move toward the target object during the period from the start to the end of the cycloidal running method in which the rotation drive wheels are driven around a point based on the pivot drive wheels as the center of rotation. That is, the moving body 1 performs a modified cycloidal running method. By performing the modified cycloidal running method, the moving body 1 releases contact with the door TO, preventing the door TO from closing.

[0089] Furthermore, according to the above-described embodiment, the positional relationship acquisition unit 410 acquires the results of measuring the external force acting on the drive motor 312 that drives the drive wheel 311, and the pivot drive wheel determination unit 420 determines, as the pivot drive wheel, the drive wheel 311 driven by the drive motor 312 that is subjected to an external force equal to or greater than a threshold. That is, the mobile object 1 uses a force sensor as a proximity sensor. Force sensors are less expensive than infrared sensors, etc., so the mobile object 1 can be configured inexpensively. Furthermore, by using a force sensor as a proximity sensor in the mobile object 1, the strain element of the force sensor can absorb impacts on the drive motor 312.

[0090] Furthermore, according to the above-described embodiment, a portion of the outline of the vehicle unit, which includes the respective drive wheels and can move the moving body, in a plan view has a shape that is recessed from the circumference of a circle connecting the respective drive wheels 311, with the central axis of the moving body 1 as the center point (centered at the moving body center point O), in the direction of the center point. In other words, the shape of the vehicle unit 300 when viewed from above is not circular. When a target object comes into contact with the driving unit of the rotating moving body 1, the recessed outline shape causes the target object to enter an area where no object is present and get caught on the driving unit. Therefore, the vehicle unit 300, which has a recessed outline shape, can easily apply force to the target object, making it easy to stop or move the target object. Specifically, the above-described shape of the moving body 1 makes it easy to open the door TO.

[0091] Furthermore, according to the above-described embodiment, the target object is an open door that can trap a part of the moving object, and is equipped with a door closer. The moving object 1, which performs a cycloidal running motion that stops the drive of the pivot drive wheels, can easily pass through the door TO. Furthermore, because the moving object 1 moves along the door TO while preventing the door TO from closing, it can pass through the door TO even if there is no area where the robot can back down while pulling the door handle to activate the door stopper.

[0092] FIG. 19 is a block diagram showing an example of the internal configuration of the control device 400 according to the embodiment. At least some of the functions of the control device 400 can be implemented using a computer. As shown in the figure, the computer includes a central processing unit 901, a RAM 902, an input / output port 903, input / output devices 904 and 905, and a bus 906. The computer itself can be implemented using existing technology. The central processing unit 901 executes instructions contained in a program read from the RAM 902 or the like. In accordance with each instruction, the central processing unit 901 writes data to the RAM 902, reads data from the RAM 902, and performs arithmetic and logical operations. The RAM 902 stores data and programs. Each element included in the RAM 902 has an address and can be accessed using the address. RAM is an abbreviation for "random access memory." The input / output port 903 is a port through which the central processing unit 901 exchanges data with external input / output devices. The input / output devices 904 and 905 are input / output devices. Input / output devices 904 and 905 exchange data with the central processing unit 901 via an input / output port 903. A bus 906 is a common communication path used within the computer. For example, the central processing unit 901 reads and writes data from and to RAM 902 via the bus 906. Also, for example, the central processing unit 901 accesses an input / output port via the bus 906. All or part of the functional units of the control device 400 may be realized using hardware such as an ASIC, a PLD, or an FPGA. All or part of the functional units may be realized by a combination of software and hardware.

[0093] Note that all or part of the functions of each unit of the control device 400 in the above-described embodiment may be realized by recording a program for realizing these functions on a computer-readable recording medium, and reading and executing the program recorded on the recording medium into a computer system. Note that the term "computer system" here includes hardware such as an OS and peripheral devices.

[0094] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design modifications can be made without departing from the spirit of the present invention. Furthermore, the configurations described in the above-described embodiments and examples can be combined. [Explanation of symbols]

[0095] 1...mobile body, 100...end effector, 200...manipulator, 300...vehicle unit, 310...first drive unit, 320...second drive unit, 330...third drive unit, 340...vehicle body, 311...drive wheel, 312...drive motor, 313...fender, 314...x-direction leaf spring, 315...y-direction leaf spring, 400...control device, 410...positional relationship acquisition unit, 420...pivot drive wheel determination unit, 430...drive control unit

Claims

1. three or more drive wheels that are each driven independently and that can move the moving body in all directions on a surface that the drive wheels contact; a positional relationship acquisition unit that acquires information about a positional relationship between each of the three or more drive wheels and a target object; a pivot drive wheel determination unit that determines one of the drive wheels as a pivot drive wheel based on the positional relationship; a drive control unit that drives rotation drive wheels other than the pivot drive wheel among the drive wheels, with the point based on the pivot drive wheel as a rotation center; A mobile body comprising:

2. the pivot drive wheel determination unit determines, as a pivot drive wheel, any drive wheel in a region in a direction of movement of the target object, within a region in which the target object moves; The moving body according to claim 1 .

3. the pivot drive wheel determination unit determines, among the three or more drive wheels, the drive wheel closest to the target object as the pivot drive wheel; The moving body according to claim 1 .

4. the pivot drive wheel determination unit determines the rotation drive wheel that is close to the target object as the pivot drive wheel in a second rotation drive as a result of a first rotation drive in which the rotation drive wheel is driven around a point based on the pivot drive wheel as a rotation center, the drive control unit drives the drive wheels other than the pivot drive wheel in the second rotation drive among the drive wheels, with a point based on the pivot drive wheel in the second rotation drive as a rotation center, The moving body according to any one of claims 1 to 3.

5. the target object moves in a tangential direction of a surface where each of the drive wheels contacts; the pivot drive wheel stops the movement of the target object by coming into contact with the target object; The moving body according to any one of claims 1 to 3.

6. the pivot drive wheel moves in the direction of the target object from the start to the end of rotational drive that drives the rotational drive wheel around a point based on the pivot drive wheel as a rotation center; The moving body according to claim 5 .

7. the positional relationship acquisition unit acquires a result of measuring an external force acting on a drive motor that drives the drive wheels; the pivot drive wheel determination unit determines, as the pivot drive wheel, the drive wheel driven by the drive motor to which an external force equal to or greater than a threshold value is applied. The moving body according to any one of claims 1 to 3.

8. a vehicle section that is provided with each of the drive wheels and that can move the moving body, and a part of the outline of the vehicle section in a plan view has a shape that is recessed from the circumference of a circle that connects the drive wheels and has a central axis of the moving body as a center point toward the center point; The moving body according to any one of claims 1 to 3.

9. the target object is a wide-open door capable of pinching a part of the moving object, and the door closer is provided; The moving body according to any one of claims 1 to 3.

10. a positional relationship acquisition step of acquiring information about the positional relationship between each of three or more drive wheels, each of which is driven separately and independently, and which can move the moving body in all directions on a surface with which each drive wheel contacts, and the target object; a pivot drive wheel determination step of determining one of the drive wheels as a pivot drive wheel based on the positional relationship; a drive control step of driving rotation drive wheels other than the pivot drive wheel among the drive wheels, with the point based on the pivot drive wheel as a rotation center; A method for controlling a moving object having the above construction.

Images