WO2018074069A1

WO2018074069A1 - Mobile body tracking control device

Info

Publication number: WO2018074069A1
Application number: PCT/JP2017/030890
Authority: WO
Inventors: 安藤　充宏; 博敏落合; ▲高▼柳　渉
Original assignee: アイシン精機株式会社
Priority date: 2016-10-20
Filing date: 2017-08-29
Publication date: 2018-04-26
Also published as: JP2018067183A

Abstract

A mobile body tracking control device is provided with: an object-identifying unit that identifies a tracking object tracked by a mobile body; an acquisition unit that, on the basis of acquisition results of an information acquisition unit that acquires information indicating the positional relationship of an object in the periphery of a mobile body, acquires at least the relative distance between the mobile body and the tracking object, and the movement direction of the tracking object; a target-setting unit that, with the movement direction of the tracking object for reference, sets the movement target position of the mobile body at a position in a direction skewed at a prescribed angle from that movement direction, and at a position of a first relative distance from the tracking object; and a control unit that controls the mobile body so as to move to the movement target position.

Description

Moving body tracking control device

Embodiments of the present invention relate to a moving body tracking control device.

Conventionally, a tracking method of a moving body has been proposed in which a movement path of an object (operator or the like) to be tracked (tracked) is calculated, a tracking path is set, and tracking (tracking) is executed. There has also been proposed a follow-up type traveling vehicle that automatically follows the operator without requiring the operator to start and stop.

Japanese Patent No. 4316477 Japanese Patent No. 4552869 JP-A-6-274223

However, since it is assumed that there are many pedestrians and obstacles in addition to the tracking target person (operator, etc.) around the moving body, a high load calculation is required for calculating the movement path of the operator. Is done. In addition, since it is also required to avoid contact with surrounding moving bodies (for example, pedestrians) other than the operator, there has been a problem that the complexity of calculating the moving route is further increased.

Therefore, one of the problems of the present invention is to provide a moving body tracking control device that can reduce the calculation load and can smoothly track (follow) a tracking target (operator, target).

The mobile body tracking control device according to the embodiment of the present invention acquires, for example, information indicating a positional relationship between a target specifying unit that specifies a tracking target object that the mobile body tracks and an object around the mobile body. Based on the acquisition result of the part, the acquisition unit for acquiring at least the relative distance between the moving object and the tracking target object and the moving direction of the tracking target object, and the moving direction of the tracking target object A target setting unit that is located on a direction deviated by a predetermined angle from the moving direction and that sets a moving target position of the moving body at a position of a first relative distance from the tracking target body; and And a control unit that controls to move to. According to this configuration, the moving body moves to a position at a predetermined angle with respect to the moving direction of the tracking target object while maintaining the first relative distance. As a result, for example, it is not necessary to estimate (calculate) the movement path of the tracking target object, and the calculation load can be reduced. In addition, since the moving body tracks the tracking target object while always existing at a predetermined position with respect to the tracking target object, the management (monitoring) of the moving object becomes easy.

For example, the target setting unit of the mobile tracking control apparatus according to the embodiment of the present invention has the moving target on a circular orbit whose center is the position of the tracking target and whose radius is defined by the first relative distance. The position may be set. According to this configuration, for example, even when there is a change in the surrounding situation of the moving object or when the tracking target object moves irregularly, the moving object is on a circular orbit with a constant radius centered on the position of the tracking target object. Therefore, a smooth tracking operation can be realized without leaving the tracking target.

The target setting unit of the mobile body tracking control device according to the embodiment of the present invention may be, for example, in a region excluding a predetermined rear region including a backward vector of the moving direction from a lateral region and a rear region of the tracking target body. The movement target position may be set. According to this configuration, the moving body performs the tracking operation so as to exist in the rear region excluding the back side from the side of the tracking target body. As a result, for example, it is possible to suppress the moving body from leading ahead of the tracking target object. Further, since the object does not move directly behind the tracking object, for example, even when the tracking object suddenly stops, it is possible to prevent the tracking object and the moving object from coming into contact with each other.

The target setting unit of the moving body tracking control device according to the embodiment of the present invention may change the first relative distance according to, for example, the surrounding state of the moving body. According to this configuration, for example, when the existence situation of the object around the moving body is normal, for example, when it is “dense” rather than “sparse”, the moving body moves closer to the tracking target object. Can be made. As a result, the moving body can be smoothly moved even when the periphery of the moving body is congested. On the other hand, if the surrounding area of the moving object is not sparse, the relative distance between the moving object and the tracking target object is increased, for example, the moving object is changed to the tracking target object in a state where the mutual feeling of pressure is reduced. Can be tracked.

For example, the acquisition unit of the mobile body tracking control device according to the embodiment of the present invention may include a second unit between the obstacle and the mobile body present around the mobile body included in the acquisition result of the information acquisition unit. When the relative distance or the second relative distance is reduced, the predicted contact time until contact with the moving body is acquired, and the target setting unit is configured such that the second relative distance is equal to or less than a predetermined distance threshold. In this case or when the predicted contact time is equal to or less than a predetermined time threshold, the movement target position may be set to a position closer to the tracking target object than the first relative distance. According to this configuration, for example, when an obstacle approaches, the smooth tracking movement of the moving body can be easily performed while reducing the possibility of contact with the obstacle.

The acquisition unit of the mobile body tracking control device according to the embodiment of the present invention is configured such that the second relative distance between the obstacle and the obstacle existing around the mobile body included in the acquisition result of the information acquisition unit. Alternatively, when the second relative distance is shortened, a contact prediction time until contact with the moving body is acquired, and the target setting unit is configured to detect when the second relative distance is equal to or less than a predetermined distance threshold. When the predicted contact time is equal to or less than a predetermined time threshold, the movement target position is set on the opposite side of the obstacle with the tracking target object interposed therebetween, and the control unit is configured so that the moving object is the obstacle. It may be controlled to move to the movement target position on the opposite side through a trajectory away from the vehicle. According to this configuration, when an obstacle approaches, the moving body moves so as to increase the relative distance from the obstacle. As a result, for example, the probability of contact with an obstacle is further reduced, and a smoother avoidance movement of the moving body with respect to the obstacle can be easily performed.

FIG. 1 is a perspective view of a wheelchair that is an example of a moving body on which the moving body tracking control device according to the embodiment is mounted. FIG. 2 is a block diagram illustrating an example of a moving body tracking system including a moving body tracking control apparatus according to the embodiment. FIG. 3 is an explanatory diagram illustrating an example of a detection range of a laser sensor that detects a surrounding situation mounted on the moving body of the moving body tracking control device according to the embodiment. FIG. 4 is a block diagram illustrating an example of a configuration of a control unit (CPU) that realizes a tracking operation realized in the ECU of the moving body tracking control device according to the embodiment. FIG. 5 is an explanatory diagram illustrating an example of the tracking position of the moving object of the moving object tracking control device according to the embodiment. FIG. 6 is an explanatory diagram illustrating an example of the movement target position of the moving object when the tracking target object travels straight ahead in the moving object tracking control device according to the embodiment. FIG. 7 is an explanatory diagram illustrating an example of the movement target position of the moving object when the tracking target object moves obliquely forward to the right in the moving object tracking control device according to the embodiment. FIG. 8 illustrates a case where the tracking target object moves to the same position as that in FIG. 7 in the moving body tracking control apparatus according to the embodiment, but the direction (movement direction) facing the position is different from that in FIG. It is explanatory drawing which shows an example of the movement target position of a moving body. FIG. 9 is a flowchart for explaining the first half of the processing procedure for realizing an example of the tracking operation of the mobile object in the mobile object tracking control device according to the embodiment. FIG. 10 is a flowchart for explaining the second half of the processing procedure for realizing an example of the tracking operation of the mobile object in the mobile object tracking control device according to the embodiment. FIG. 11 is an explanatory diagram illustrating an example of the tracking position of the moving object when the degree of congestion around the moving object is low in the moving object tracking control device according to the embodiment. FIG. 12 is an explanatory diagram illustrating an example of the tracking position of the moving object when the degree of congestion around the moving object is higher than that in FIG. 11 in the moving object tracking control device according to the embodiment. FIG. 13 is an explanatory diagram illustrating an example of an avoidance position of a moving object when an obstacle approaches from the front of the moving object and an example of a moving track for moving to the avoidance position in the moving object tracking control device according to the embodiment. is there. FIG. 14 is an explanatory diagram illustrating an example of an avoidance position of a moving object when an obstacle approaches from the rear of the moving object and a moving trajectory for moving to the avoidance position in the moving object tracking control device according to the embodiment. is there.

Hereinafter, exemplary embodiments of the present invention will be disclosed. The configuration of the embodiment shown below and the operations, results, and effects brought about by the configuration are examples. The present invention can be realized by configurations other than those disclosed in the following embodiments, and at least one of various effects based on the basic configuration and derivative effects can be obtained. .

In this embodiment, the moving body tracking control device can be applied to a small moving body such as a “wheelchair” as shown in FIG. In the embodiment described below, a “wheelchair” is shown as an example of the moving body, but the present invention is not limited to this. For example, as a moving means for healthy persons, a moving vehicle that rides in a sitting posture or a standing posture may be used. The moving body is a vehicle including a driving source such as a motor, and may include a normal traveling mode in which the user (passenger) moves by maneuvering (driving), or automatically specifying a tracking target object. A tracking travel mode for tracking may be provided. Moreover, you may provide the self-propelled mode which a user gives a driving force to a moving body and moves by himself / herself using a hand or a foot. The moving body may be an unmanned vehicle including a loading platform on which an object other than a human (eg, luggage, animal) can be loaded. In addition, the moving body may run alone, or a plurality of moving bodies may be connected, or a plurality of moving bodies may be moved in a state where they are connected in a separated state.

FIG. 1 shows a specific configuration in which a moving body tracking control device is mounted on a wheelchair 10 as an example of a moving body. The wheelchair 10 is a foldable chair in which a seat 14 and a back support 16 formed of, for example, a flexible cloth material or a resin material are fixed to a metal frame 12. A retractable foot support 18 is provided at the lower front portion of the seat 14 so that a user (user) can put his / her foot in a sitting position. A leg support 20 is provided between the foot support 18 and the seat 14 to support the inflated shin and prevent the foot from entering the lower side of the seat 14 when the user is seated on the seat 14. ing.

Driving wheels 22 (left driving wheel 22L and right driving wheel 22R) are arranged on the left and right sides of the seat 14. A ring-shaped hand rim 22 a is integrally fixed to the drive wheel 22 outside the drive wheel 22. The hand rim 22a realizes a self-running mode in which the user sitting on the seat 14 grips and rotates the hand rim 22a by hand to drive the driving wheel 22 and move the wheelchair 10. Moreover, the drive wheel 22 of the wheelchair 10 of this embodiment is provided with the drive system 24, and is comprised so that automatic driving | running | working can be performed. The drive wheel 22 is provided with, for example, a drum brake system 26, and the drive wheel 22 can be decelerated, stopped, and held in a stopped state. The brake system 26 can also be integrated with the drive system 24.

A pair of casters 28 for determining the traveling direction of the wheelchair 10 are provided in front of the drive wheels 22. The casters 28 are connected to a steering system 30 composed of gears and the like. The steering system 30 allows the caster 28 to turn freely in a self-propelled mode in which the user rotates the hand rim 22a to move the wheelchair 10 or when a companion or the like grips the handwheel 12a to push the wheelchair 10 to move. To do. That is, the steering direction is not restricted. On the other hand, when the driving wheel 22 is driven in the normal traveling mode in which the driving wheel 22 is rotated by the driving system 24 or the tracking traveling mode described later, the steering system 30 performs a turning instruction by the user or tracking control by the ECU 44 (see FIG. 2). The caster 28 is controlled to turn in a predetermined direction to determine the traveling direction of the wheelchair 10.

The drive system 24, the brake system 26, and the steering system 30 can be driven by receiving power supply from the battery 32a of the battery system 32 disposed on the lower surface of the seat 14, for example.

Further, a control box 34 is arranged at a position where the user can reach in a posture where the user is seated on the seat 14, for example, at a side of the seat 14. The control box 34 contains a control unit for causing the wheelchair 10 to travel in the normal travel mode or the tracking travel mode. In addition, the control box 34 may be provided with an operation unit 36 for instructing a moving speed and a moving direction when the user moves the wheelchair 10 in the normal driving mode. The operation unit 36 can be a joystick that can be tilted in an arbitrary direction of 360 °, for example. In this case, the traveling direction of the wheelchair 10 can be instructed in the direction in which the joystick is tilted, and the moving speed of the wheelchair 10 can be instructed by the amount by which the joystick is tilted. The wheelchair 10 can be stopped by returning the joystick to the neutral position (upright position). In this case, the actuator 26a of the brake system 26 may be driven to maintain the stopped state of the drive wheels 22.

Also, the control box 34 is provided with a laser sensor 38 (front sensor 38F) as an example of an information acquisition unit that acquires information indicating the positional relationship of objects existing in the area mainly in front of the wheelchair 10. Similarly, a laser sensor 38 (rear sensor 38 </ b> R) that acquires information indicating the positional relationship of objects existing there is provided for a region mainly behind the wheelchair 10. In the case of FIG. 1, as an example, the rear sensor 38 </ b> R is supported by a casing constituting the battery system 32. It is desirable that the front sensor 38F and the rear sensor 38R can cover a range around the wheelchair 10, for example, a range of 360 °. The positions where the front sensor 38F and the rear sensor 38R are installed are only examples, and can be appropriately changed as long as the situation around the wheelchair 10 can be acquired. Moreover, although this embodiment showed the example which provided the two laser sensors 38, if the range around the wheelchair 10 (for example, the range of 360 degrees) can be covered, it may be one piece or three or more pieces. By increasing the number of laser sensors 38, the non-detection range (dead angle) can be reduced or eliminated.

In addition, the wheelchair 10 is provided with a hand brake lever 40 that keeps the stop state of the drive wheel 22 by bringing the brake pad 40 a into contact with the tire surface of the drive wheel 22. Further, for example, on the opposite side of the control box 34, a monitor device 42 that provides the user with various information such as the running state of the wheelchair 10 and the surrounding situation may be provided. The monitor device 42 can be fixed in an arbitrary posture, for example, by adjusting the angle of the support arm, making it easy to ensure the visibility in the posture in which the user is seated on the seat 14, and is obstructive during the sitting posture and the seating operation. It can be arranged so that it does not become.

FIG. 2 is a block diagram illustrating an example of the mobile tracking system 100 including the mobile tracking control device according to the embodiment. ECU44 (electronic control unit), which is the main configuration of the moving body tracking control device, and various systems, various sensors, etc. are electrically connected via the interface 102 to realize traveling control (tracking control) of the wheelchair 10 as the moving body. To do. For example, the drive system 24, the brake system 26, the steering system 30, the battery system 32, the laser sensor 38, the steering angle sensor 46, the wheel speed sensor 48, and the like are connected to the interface 102.

The drive system 24 includes an actuator 24a and a torque sensor 24b. The drive system 24 is electrically controlled by the ECU 44 or the like, and drives the actuator 24a (for example, a motor) when the wheelchair 10 is in the normal travel mode or the tracking travel mode. The drive system 24 adjusts the speed and torque of the drive wheels 22 and moves the wheelchair 10 in a forward direction or a reverse direction at a desired speed (for example, a speed indicated by an operation amount of the operation unit 36). The torque sensor 24b detects the torque of the actuator 24a, and the ECU 44 analyzes the torque generated in the actuator 24a, thereby correcting the command value of the actuator 24a and improving the speed control accuracy of the wheelchair 10. Let

The brake system 26 includes an actuator 26a and a brake sensor 26b. The brake system 26 is electrically controlled by the ECU 44 or the like, and operates an actuator 26a (for example, a piston) to change, for example, the pressing state of the brake shoe against the drum of the drum brake. By changing the pressing state of the brake shoe, the speed of the drive wheel 22 is adjusted, the drive wheel 22 is stopped, or the stop state of the drive wheel 22 is maintained. The brake sensor 26b is a sensor that detects an operation state (depression amount or the like) of a brake pedal disposed on the foot support 18, for example.

The steering system 30 includes an actuator 30a and a torque sensor 30b. The steering system 30 is electrically controlled by the ECU 44 and the like to apply torque to gears and the like by driving an actuator 30a (for example, a motor) when the wheelchair 10 is driven in the normal driving mode or the tracking driving mode. The caster 28 is turned. As a result, the traveling direction of the wheelchair 10 is changed by changing the direction in which the caster 28 faces (the steering direction). In this case, the actuator 30a may steer one caster 28, or may steer the left and right casters 28. Further, the torque sensor 30b detects, for example, torque generated on the turning shaft of the caster 28, and detects whether the turning state of the caster 28 by the actuator 30a is being executed as instructed. The ECU 44 performs feedback control of the actuator 30a according to the detection result, and improves the turning accuracy of the caster 28.

The steering angle sensor 46 is, for example, a sensor that detects the direction of the caster 28. The rudder angle sensor 46 is configured using, for example, a hall element, and acquires, for example, an angle in the positive direction (clockwise direction) and a negative direction (counterclockwise direction) with respect to the front direction of the wheelchair 10. To do. The wheel speed sensor 48 is, for example, a sensor that detects the amount of rotation of the drive wheels 22 and the number of rotations per unit time. The wheel speed sensor 48 is disposed on each drive wheel 22 and outputs a wheel speed pulse number indicating the rotation speed detected by each drive wheel 22 as a sensor value. The wheel speed sensor 48 can be configured using, for example, a hall element. The ECU 44 calculates the amount of movement of the wheelchair 10 based on the sensor value acquired from the wheel speed sensor 48 and executes various controls. When calculating the vehicle speed of the vehicle 1 based on the sensor value of each wheel speed sensor 48, the ECU 44 determines the vehicle speed of the wheelchair 10 based on the speed of the drive wheel 22 having the smaller sensor value of the left and right drive wheels 22. Execute various controls.

The battery system 32 includes a battery 32a for charging / discharging, a voltage sensor 32b, and a current sensor 32c. The battery 32a may be of a type that is connected to an external power source and charged, or may be charged when the drive wheels 22 rotate in the normal travel mode. Moreover, you may charge by the regeneration operation | movement of the actuator 24a (motor) of the drive system 24. FIG. A combination thereof may also be used. The voltage sensor 32b and the current sensor 32c manage the voltage value and the current value when the battery 32a is charged and discharged. Moreover, when charging the battery 32a by regeneration, the voltage sensor 32b and the current sensor 32c are managed so as to maintain the battery 32a in an optimal charging state.

The laser sensor 38 (front sensor 38F, rear sensor 38R) functions as an information acquisition unit that acquires information indicating the positional relationship of objects around the wheelchair 10 as a moving body. The laser sensor 38 is reflected when a laser beam emitted from a light source (laser diode or the like) inside the sensor hits a measurement target (for example, a tracking target or an obstacle) and is received by a light receiving element. The distance to the position where the laser beam is reflected is calculated by evaluating and calculating the reflected light received at this time. Further, by comparing the information in time series, the moving direction when the measurement object moves can be calculated. As shown in FIG. 3, the front sensor 38F of the laser sensor 38 is directed to the front of the wheelchair 10 and has, for example, a first region FE including the front at a detection angle θF as a detection range. Further, the rear sensor 38R is directed to the rear of the wheelchair 10, and, for example, the second region RE including the rear and the side at the detection angle θR is set as a detection range. Note that when a plurality of laser sensors 38 are combined to form 360 ° around the wheelchair 10 as a detection region, a non-detection region (dead angle) may be formed. In the example shown in FIG. 3, the first region FE and the second region RE overlap with each other in the overlapping region CE, and the non-detection region DE is reduced. In the case of FIG. 3, there is a non-detection area DE, but since it is the closest position in front of the wheelchair 10, it is a blind spot as the laser sensor 38, but it is an area that can be easily visually confirmed by a user sitting on the wheelchair 10. The control impact is minimal (substantially negligible).

The interface 102 is further connected to an ECU 44, a monitor device 42, and the like. The ECU 44 can control the drive system 24, the brake system 26, the steering system 30, the battery system 32, and the like by sending a control signal through the interface 102. Further, the ECU 44 detects detection results of the torque sensor 24b, the brake sensor 26b, the torque sensor 30b, the voltage sensor 32b, the current sensor 32c, the rudder angle sensor 46, the wheel speed sensor 48, the laser sensor 38, etc. via the interface 102, An operation signal from the operation unit 36 or the like can be received.

The ECU 44 includes, for example, a CPU 44a (central processing unit), a ROM 44b (read only memory), a RAM 44c (random access memory), an SSD 44d (solid state drive, flash memory), and the like. In the tracking driving mode, the CPU 44a specifies, for example, a tracking target object (for example, a companion, a leader, a leading conductor, etc.) to be tracked by the wheelchair 10, and keeps a relative distance from the tracking target object constant. A process for tracking the wheelchair 10 at a fixed position on the basis of the tracking object is performed. In the normal traveling mode, the CPU 44a controls the drive system 24, the steering system 30, the battery system 32, and the like so as to realize traveling of the wheelchair 10 according to the moving direction and moving speed instructed by the user via the operation unit 36. To do. Further, when the wheelchair 10 is driven in the self-propelled mode, the drive system 24 and the steering system 30 are disconnected from the system so that the drive wheels 22 can be easily rotated with a light load and the casters 28 are directed in an arbitrary direction. To do. In this case, the brake system 26 may be in a controllable state or may be used as an emergency stop brake in the self-propelled mode. The CPU 44a reads a program stored (installed) in a non-volatile storage device such as the ROM 44b, and executes arithmetic processing according to the program.

The RAM 44c temporarily stores various data used in the calculation by the CPU 44a. Further, the SSD 44d is a rewritable nonvolatile storage unit, and can store data even when the power of the ECU 44 is turned off. Note that the CPU 44a, ROM 44b, RAM 44c and the like can be integrated in the same package. Further, the ECU 44 may have a configuration in which another logical operation processor, a logic circuit, or the like such as a DSP (digital signal processor) is used instead of the CPU 44a. Further, an HDD (hard disk drive) may be provided instead of the SSD 44d.

The monitor device 42 includes a display device 42a, an operation input unit 42b, and an audio output device 42c. The display device 42a may be, for example, an LCD (liquid crystal display), an OELD (organic electroluminescent display), or the like. You may display the surroundings of the wheelchair 10, for example, the position of an obstacle, etc. on the display device 42a. In particular, it is possible to capture and display a rear situation or the like that is difficult to see in the sitting posture with an imaging device (camera). Further, when the wheelchair 10 is in the normal traveling mode or the tracking traveling mode, the control state of the wheelchair 10, for example, the charging state of the battery 32 a or the traveling speed may be displayed. In addition, the display device 42a may be a simple device that includes only an indicator lamp. In this case, the approach of an obstacle may be displayed by a change in display mode such as a change in display color of the indicator lamp or blinking. The operation input unit 42b can be configured with a switch, a dial, a push button, and the like. When the display device 42a is configured with a touch panel or the like, the operation input unit 42b may be realized on the display screen of the display device 42a. The voice output device 42c outputs a message (such as an alarm) when the wheelchair 10 is in the normal travel mode or the tracking travel mode, for example, when suddenly stopping, when changing course, or when an obstacle exists. Alternatively, the state of the battery 32a may be notified.

The configuration, arrangement, electrical connection form, and the like of the various sensors and actuators described above are merely examples, and can be set (changed) in various ways.

The CPU 44a included in the ECU 44 includes various modules as shown in FIG. 4 in order to realize the tracking traveling as described above. The CPU 44a includes an acquisition unit 58, a target identification unit 60, an obstacle identification unit 62, a target setting unit 64, a travel control unit 66, a display control unit 68, a voice control unit 70, an output unit 72, and the like as modules. The acquisition unit 58 includes a relative distance acquisition unit 58a, a movement direction acquisition unit 58b, a movement speed acquisition unit 58c, an obstacle distance calculation unit 58d, a contact prediction time calculation unit 58e, and the like. The target setting unit 64 includes an orbital circle setting unit 64a, a movement target position setting unit 64b, a surrounding situation recognition unit 64c, and the like. The traveling control unit 66 includes a straight traveling speed calculation unit 66a, a turning speed calculation unit 66b, a steering angle setting unit 66c, a battery control unit 66d, a motor control unit 66e, and the like. These modules can be realized by reading a program installed and stored in a storage device such as the ROM 44b and executing it. The CPU 44a can guide and track the wheelchair 10 in a predetermined direction so as to be separated by a predetermined relative distance, for example, based on the tracking target object by executing processing by various modules.

The acquisition unit 58 is a relative distance between the wheelchair 10 and its surrounding objects based on the acquisition result of the laser sensor 38 (information acquisition unit) that acquires information indicating the positional relationship between objects around the wheelchair 10 as a moving body. And the moving direction of the object. The laser sensor 38 transmits and receives laser light every 1/16 second, for example. Then, based on the detection result of the laser sensor 38, the relative distance acquisition unit 58a detects the presence or absence of an object around the wheelchair 10 and the relative distance between the object and the wheelchair 10 when an object exists.

The moving direction acquisition unit 58b acquires the presence / absence and moving direction of the object by comparing the detection results of the laser sensor 38 in time series. For example, by comparing the position of an object at a certain detection timing with the position of the same object at the next detection timing, a direction vector that connects the two can be obtained. This direction vector is the moving direction of the object.

The moving speed acquisition unit 58c calculates the moving speed of the object detected around the wheelchair 10 by differentiating the detection result of the laser sensor 38.

The target specifying unit 60 specifies a tracking target object that the wheelchair 10 tracks from among objects existing around the wheelchair 10 acquired by the acquiring unit 58. For example, a moving object (for example, a human being, an animal, or another moving object) present at a position closest to the wheelchair 10 may be used as the tracking target object. In addition, the situation around the wheelchair 10 is imaged by an imaging unit (for example, a camera), an object included in the captured image is displayed on the display device 42a, and the tracking target object is specified by the user via the operation input unit 42b or the like. May be specified. In addition, an object to be tracked is possessed by a transmitter (for example, a beacon), and the target specifying unit 60 receives a signal from the transmitter, so that the object carrying the transmitter is regarded as a tracking target. Also good. In addition, a tracking target object may be specified by extracting an object included in a captured image captured by an imaging unit (for example, a camera) using a known pattern matching technique or the like. On the other hand, the obstacle specifying unit 62 specifies an object existing around the wheelchair 10 as an obstacle other than the object (tracking target object) specified by the target specifying unit 60.

The obstacle distance calculating unit 58d calculates a relative distance (second relative distance) between the obstacle specified by the obstacle specifying unit 62 and the wheelchair 10. The moving speed acquisition unit 58c also acquires the moving speed for the obstacle specified by the obstacle specifying unit 62. Then, the predicted contact time calculation unit 58e uses (compares) the obstacle movement speed acquired by the movement speed acquisition part 58c and the speed of the wheelchair 10 based on the sensor value of the wheel speed sensor 48, and The predicted contact time until the wheelchair 10 comes into contact is calculated. The second relative distance calculated by the obstacle distance calculating unit 58d and the predicted contact time calculated by the predicted contact time calculating unit 58e are used when the wheelchair 10 determines an avoidance exercise when avoiding the obstacle. For example, when the second relative distance between the obstacle present around the wheelchair 10 and the wheelchair 10 is equal to or less than a predetermined distance threshold (for example, 3 m or less), the CPU 44a executes an avoidance exercise to avoid the obstacle. Similarly, when the second relative distance between the wheelchair 10 and the obstacle is reduced, and the predicted contact time until the wheelchair 10 comes into contact is less than a predetermined time threshold (for example, 5 seconds or less), the CPU 44a Execute avoidance exercise, avoiding obstacles. The avoidance movement is realized by reducing the radius R1 of the concentric circle 76a, or changing the tracking position (position viewed from the target 74) of the wheelchair 10 to the side with few obstacles with the target 74 interposed therebetween.

The target setting unit 64 determines the movement target position of the wheelchair 10 based on the tracking target object determined by the target specifying unit 60. In the case of the moving body tracking system 100 according to the present embodiment, the movement target position of the wheelchair 10 as a moving body is, for example, a tracking interval (first step) centered on a target 74 as a tracking target body as shown in FIG. Relative distance) is set on a concentric circle of radius R1. The orbital circle setting unit 64a always sets a concentric circle 76a (circular orbit) having a radius R1 regardless of whether the target 74 is moved or stopped around the tracking target object (target 74) identified by the object identifying unit 60.

In addition, the movement target position setting unit 64b is the target movement direction of the target 74 acquired by the movement direction acquisition unit 58b on the concentric circle 76a set by the trajectory circle setting unit 64a with respect to the target 74 specified by the target specifying unit 60. The movement target position of the wheelchair 10 is set at a position where the tracking angle θ is based on P. As an example in the case of FIG. 5, the movement target position of the wheelchair 10 is set at a position rotated (shifted) by a predetermined angle (tracking angle θ) counterclockwise. The movement target position setting unit 64b excludes a predetermined rear region (release angle θN) including the reverse vector PV in the target moving direction P from the side and rear regions of the target 74 (tracking target) as the tracking angle θ. Set the movement target position in the area. That is, the movement target position of the wheelchair 10 is not set to a position immediately behind the target 74. By performing such setting, for example, when the wheelchair 10 is moving while tracking the target 74, even if the target 74 suddenly stops or suddenly changes direction, the wheelchair 10 Contact with 74 can be avoided. In the case of FIG. 5, an example in which the release angle θN is set at 45 ° left and right (total 90 °) with the reverse direction vector PV as the center is shown. In the case of FIG. 5, the position of the wheelchair 10 when the target 74 moves to the illustrated position is shown. Thus, when the target 74 moves in the direction indicated by the target moving direction P at the target speed VT, the wheelchair 10 moves in the same manner, and moves while maintaining the relative positional relationship between the target 74 and the wheelchair 10. Contact with can also be easily avoided.

The movement target position of the wheelchair 10 may be basically set in an area excluding the rear area (release angle θN) on the concentric circle 76a. However, in order to give the wheelchair 10 a more secure feeling. Is preferably set at a position behind the target 74 (position defined by the standard angle θG). In this case, the target 74 (in this case, an attendant) always enters the field of view of the user sitting on the wheelchair 10, and a sense of security can be obtained. Note that since the human field of view is, for example, about 120 °, the target 74 (in this case, an attendant) confirms the wheelchair 10 existing at the standard angle θG only by slightly shaking the head while facing the target moving direction P. be able to. As a result, for example, the attendant who is the target 74 can move while confirming the user sitting on the wheelchair 10 (for example, while having a conversation). Even when the wheelchair 10 being tracked is separated from the target 74 for some reason, the situation can be recognized quickly.

The surrounding situation recognition unit 64c detects the degree of congestion of obstacles around the wheelchair 10 specified by the obstacle specifying unit 62. For example, the ROM 44b holds in advance a congestion degree M indicating the density of obstacles per unit area, and whether the surroundings of the wheelchair 10 are in a “dense” state with a congestion degree M or higher or a “sparse” state with a congestion degree M or less. Recognize what it is. When the surrounding situation recognized by the surrounding situation recognition unit 64c is “sparse”, the orbit circle setting unit 64a sets the radius R1 (first relative distance) of the orbit circle to, for example, a standard distance (eg, 1 m). By maintaining the relative distance between the wheelchair 10 and the target 74 at, for example, 1 m, it is possible to reduce the feeling of pressure on each other and to reduce the feeling of anxiety due to being too far away. On the other hand, when the surrounding situation recognized by the surrounding situation recognition unit 64c is “dense”, the orbital circle setting unit 64a decreases the radius R1 (first relative distance, for example, radius 1 m) of the orbital circle (for example, radius 0). 5m), the wheelchair 10 is moved closer to the target 74 so that the wheelchair 10 can easily travel even in a crowded state.

The traveling control unit 66 performs overall control related to traveling of the wheelchair 10. When the wheelchair 10 tracks the target 74 in the tracking travel mode, the straight speed calculation unit 66a is based on the moving speed of the target 74 acquired by the moving speed acquiring unit 58c, that is, the rotation of the driving wheel 22 Calculate the speed. When the wheelchair 10 tracks the target 74, the turning speed calculation unit 66b sets the current speed of the wheelchair 10 based on the movement direction of the target 74 acquired by the movement direction acquisition unit 58b and the sensor value acquired by the wheel speed sensor 48. Accordingly, the turning speed ωM of the caster 28 is calculated. For example, when the target 74 suddenly changes its traveling direction, the turning speed ωM becomes faster, and when the target 74 changes its traveling direction slowly, the turning speed ωM becomes slower. The steering angle setting unit 66c determines the control angle of the caster 28, that is, the control amount of the actuator 30a of the steering system 30, so that the wheelchair 10 reaches the movement target position set by the movement target position setting unit 64b.

The battery control unit 66d allows the drive system 24 to realize a speed at which the wheelchair 10 can move to the movement target position set by the movement target position setting unit 64b until the movement target position in the next control cycle is determined. The output value of the battery system 32 is controlled. The battery control unit 66d controls charging / discharging of the battery 32a and manages the battery amount. The motor control unit 66e acquires the load state of the actuator 24a (motor) based on the torque value obtained from the torque sensor 24b, and moves the movement target position set by the movement target position setting unit 64b to the movement target in the next control cycle. Increase / decrease the speed so that it can move before the position is determined. For example, the output value of the actuator 24a (motor) is determined according to the road surface state (gradient state, uneven state, etc.).

The display control unit 68 displays the traveling state (speed, traveling direction, etc.) of the wheelchair 10 in the normal traveling mode and the tracking traveling mode, displays the charging state of the battery 32a, and the number of obstacles around the wheelchair 10. And processing for displaying the existence position and the like. The voice control unit 70 executes processing for providing information on the driving state of the wheelchair 10 or an alarm when there is an obstacle or the like in the normal traveling mode or the tracking traveling mode. The output unit 72 outputs the control results from the travel control unit 66 to each system, and outputs the control results from the display control unit 68 and the voice control unit 70 to the monitor device 42.

In the normal travel mode, the travel control unit 66 follows the operation content of the operation unit 36 (for example, the direction and amount of tilting of the joystick), and the straight travel speed calculation unit 66a, the turning speed calculation unit 66b, and the steering angle setting unit 66c. Then, control of the battery control unit 66d, the motor control unit 66e, and the like is executed, and the wheelchair 10 is driven according to the user's instructions.

An example of setting the movement target position when the wheelchair 10 configured in this way tracks the target 74 will be described with reference to FIGS. In the examples shown in FIG. 6 to FIG. 8, the movement target position is set when there is no obstacle around the wheelchair 10 or when the obstacle is present in a “sparse” state (non-congested state). Shows the case.

FIG. 6 shows the movement target position 78 of the wheelchair 10 when the target 74 that is the tracking object moves straight from the current position in the target movement direction P to the position indicated by the dotted line at the target speed VT. The object specifying unit 60 first specifies the target 74 based on the positional relationship of objects around the wheelchair 10 acquired by the acquiring unit 58. For example, an object existing at a position closest to the wheelchair 10 is set as the target 74. Further, the orbital circle setting unit 64a acquires the degree of congestion around the wheelchair 10 based on the recognition result of the surrounding state recognition unit 64c, and when it is not crowded as shown in FIG. Relative distance). At this time, if the wheelchair 10 does not exist on the concentric circle 76a, the traveling control unit 66 uses the target moving direction P of the target 74 acquired by the moving direction acquiring unit 58b as a reference on the concentric circle 76a centered on the target 74. The wheelchair 10 is moved to the position moved counterclockwise by the tracking angle θ, and this position is set as the current position of the wheelchair 10 corresponding to the current position of the target 74. When the target 74 moves straight in the target movement direction P as shown in FIG. 6, the concentric circle 76a having the radius R1 is similarly moved straight in the target movement direction P, that is, a position centered on the target 74 indicated by a dotted line. Set to Then, the movement target position 78 is on a concentric circle 76a set around the target 74 indicated by a dotted line, and on the concentric circle 76a centered on the target 74 with reference to the target moving direction P of the target 74 indicated by the dotted line. Only the position moved counterclockwise is set. The straight speed calculation unit 66a calculates the straight speed VM of the wheelchair 10 such that the wheelchair 10 reaches the movement target position 78 until the next movement target position is set. In this case, since the target 74 is only going straight in the target moving direction P, the turning speed calculation unit 66b does not calculate the turning speed ωθ. Thus, when moving straight in the target moving direction P as in the case of the target 74 indicated by the dotted line, the relative positional relationship of the wheelchair 10 viewed from the target 74 is not changed, and the target 74 can be tracked.

FIG. 7 shows the movement target of the wheelchair 10 when the target 74 as the tracking target object performs a turning movement from the current position and moves to the position of the target 74 indicated by the dotted line with the turning direction as the target movement direction P. A position 78 is shown. Also in this case, the target specifying unit 60 specifies the target 74 based on the positional relationship of the objects around the wheelchair 10 acquired by the acquiring unit 58. Further, the orbital circle setting unit 64a acquires the degree of congestion around the wheelchair 10 based on the recognition result of the surrounding situation recognition unit 64c, and in the case of non-congestion as shown in FIG. 7, a concentric circle 76a having a radius R1. Set (first relative distance). Even when the target 74 turns straight as shown in FIG. 7 and moves straight in the target movement direction P, the concentric circle 76a having the radius R1 is set to a position centered on the target 74 indicated by the dotted line. The moving target position 78 is a tracking angle on a concentric circle 76 a centered on the dotted target 74 and on a concentric circle 76 a centered on the dotted target 74 with reference to the target moving direction P of the dotted target 74. It is set at a position moved counterclockwise by θ. The straight speed calculation unit 66a calculates the straight speed VM of the wheelchair 10 such that the wheelchair 10 reaches the movement target position until the next movement target position 78 is set. In this case, since the target 74 is turning, the turning speed calculation unit 66b calculates the turning speed ωθ that turns so that the wheelchair 10 reaches the movement target position before the next movement target position 78 is set. . Thus, after the target 74 turns, even when the target 74 moves straight with the target moving direction P in the turning direction, the relative positional relationship of the wheelchair 10 viewed from the target 74 does not change, and the target 74 can be tracked. it can.

FIG. 8 shows the wheelchair 10 in a case where the target moving direction P is a direction different from the turning direction, such as the target 74 indicated by the dotted line, after the target 74 as the tracking target object makes a turning movement from the current position. A movement target position 78 is shown. In this case, the position of the dotted target 74 is the same as the position of the dotted target 74 in FIG. 7, but the direction in which the dotted target 74 is currently facing is different. Also in this case, the target specifying unit 60 specifies the target 74 based on the positional relationship of the objects around the wheelchair 10 acquired by the acquiring unit 58. Further, the orbital circle setting unit 64a acquires the degree of congestion around the wheelchair 10 based on the recognition result of the surrounding situation recognition unit 64c, and when it is not crowded as shown in FIG. 8, the concentric circle 76a having the radius R1. Set (first relative distance). When the dotted target 74 moves straight in the target moving direction P after turning as shown in FIG. 8, the concentric circle 76 a with the radius R <b> 1 is set at a position centered on the dotted target 74. The moving target position 78 is a tracking angle on a concentric circle 76 a centered on the dotted target 74 and on a concentric circle 76 a centered on the dotted target 74 with reference to the target moving direction P of the dotted target 74. It is set at a position moved counterclockwise by θ. In this case, since the direction of the target movement direction P is different between the dotted line target 74 in FIG. 7 and the dotted line target 74 in FIG. 8, the movement target position 78 set by the tracking angle θ with respect to the target movement direction P is set. The position is different from the position of the movement target position 78 in FIG. The straight speed calculation unit 66a calculates the straight speed VM of the wheelchair 10 such that the wheelchair 10 reaches the movement target position 78 until the next movement target position 78 is set. Also in this case, since the target 74 is turning, the turning speed calculation unit 66b sets the turning speed ωθ for turning so that the wheelchair 10 reaches the moving target position 78 until the next moving target position 78 is set. calculate. Thus, since the position of the movement target position 78 is determined according to the target movement direction P after the target 74 turns, the relative positional relationship of the wheelchair 10 viewed from the target 74 is not changed, and the target 74 is tracked. be able to. 6 to 8 are executed in combination, the wheelchair 10 can be tracked in a fixed relative positional relationship regardless of the direction of movement of the target 74.

An example of a processing procedure for realizing an example of the tracking operation of the wheelchair 10 as described above will be described with reference to the flowcharts of FIGS. 9 and 10. FIG. 9 is a flowchart for explaining the first half of the process, and FIG. 10 is a flowchart for explaining the second half of the process.

First, the CPU 44a, for example, determines whether the tracking traveling mode for identifying and tracking the target 74 is selected as the traveling mode of the wheelchair 10 based on the operation state of the operation input unit 42b of the monitor device 42 or the like. It is detected whether the normal driving mode which moves the wheelchair 10 by operating 36 is selected (S100). When neither the tracking driving mode nor the normal driving mode is set, that is, in the self-running mode, the flowcharts of FIGS. 9 and 10 are not executed, and the wheelchair 10 turns the left and right hand rims 22a (drive wheels 22) by the user himself / herself. Move by.

When the CPU 44a detects that the tracking travel mode is selected (Yes in S100), the display control unit 68 outputs a control signal indicating that it is the tracking travel mode via the output unit 72, and the display device A display such as “in control of tracking driving mode” is performed on 42a (S102). Subsequently, the acquisition unit 58 acquires the surrounding situation of the wheelchair 10 (such as the positional relationship of objects existing around the wheelchair 10) via the laser sensor 38 (S104). Further, the target specifying unit 60 specifies the tracking target body (target 74) from among the objects existing around the wheelchair 10 (S106). In this case, there are various methods for specifying the target 74. For example, an object closest to the wheelchair 10 among the objects detected by the acquisition unit 58 may be used as the target 74. In another embodiment, the target 74 may be specified by previously carrying a transmitter such as a beacon with the target 74 and acquiring the signal. In another embodiment, target 74 may be specified based on the image acquired by the imaging part with which wheelchair 10 is provided. The target 74 may be specified by combining these methods. For example, when the density of objects existing around the wheelchair 10 is “dense”, a method using a transmitter such as a beacon is advantageous in that the target 74 can be quickly identified. Further, when the density of objects existing around the wheelchair 10 is “sparse”, when the closest object is specified as the target 74, the processing load is small, and a device such as a beacon is unnecessary, which is costly. But it is advantageous. When performing image processing, it is advantageous in that the type of target 74 to be specified can be easily changed and the specification system can be improved without using a device such as a beacon.

When the identification of the target 74 is completed (Yes in S108), the relative distance acquisition unit 58a acquires the relative distance of the target 74, and the movement direction acquisition unit 58b moves the movement direction of the target 74 based on time series information of the relative distance. Is acquired (S110). When the target 74 cannot be specified (No in S108), the target 74 specifying process is continuously executed.

Subsequently, the surrounding state recognition unit 64c calculates the congestion state around the wheelchair 10 based on the object presence information acquired by the relative distance acquisition unit 58a, and compares it with the congestion degree M previously stored in the ROM 44b or the like (S112). ). When the congestion degree around the wheelchair 10 is less than the predetermined congestion degree M (No in S112), for example, the surrounding situation recognized by the surrounding situation recognition unit 64c moves the target around the wheelchair 10 as shown in FIG. This is a case of “sparse” in which there are several pedestrians 80a (walking speed VSa) and pedestrians 80b (walking speed VSb) in addition to the target 74 having the target speed VT in the direction P. In this case, the orbital circle setting unit 64a has a concentric circle 76a (first step) having a larger radius R1 than in the case of “dense” such as pedestrian 80a (walking speed VSa) to pedestrian 80g (walking speed VSg) as shown in FIG. 1 orbital circle) is set (S114). The first orbit circle may be a circle whose first relative distance is a standard distance (1 m), for example. On the other hand, when the congestion degree around the wheelchair 10 is equal to or greater than the predetermined congestion degree M (Yes in S112), for example, the surrounding situation recognized by the surrounding situation recognition unit 64c is around the wheelchair 10 as shown in FIG. This is a “dense” case where there are a large number of pedestrians 80a (walking speed VSa) to pedestrian 80g (walking speed VSg) in addition to the target 74. In this case, as shown in FIG. 11, the orbital circle setting unit 64a sets a concentric circle 76b (second orbital circle) having a smaller radius R2 than when the

pedestrians

80a and 80b are “sparse” (S116). The second orbit circle may be a 0.5 m circle whose first relative distance is half the standard distance (for example, 1 m). By properly using the first orbit circle and the second orbit circle according to the surrounding situation, it is easy to avoid obstacles and to move the wheelchair 10 easily. In addition, since the relative distance between the target 74 and the wheelchair 10 changes according to the surrounding conditions at that time, the target 74 and the wheelchair 10 are too close to each other, causing a feeling of pressure, and conversely , You can avoid feeling too anxious about being too far away. In the case of FIGS. 11 and 12, the movement target position of the wheelchair 10 is set to be directly beside the target 74 as an example.

The CPU 44a determines whether there is an obstacle to be avoided around the wheelchair 10 based on the recognition result of the surrounding situation recognition unit 64c (S118). For example, when the second relative distance between the obstacle calculated by the obstacle distance calculation unit 58d and the wheelchair 10 is longer than a predetermined distance threshold (for example, 3 m or more), there is no obstacle to be avoided. Is determined. Alternatively, when the predicted contact time until the obstacle calculated by the predicted contact time calculation unit 58e contacts the wheelchair 10 is longer than a predetermined time threshold (for example, 5 seconds or more), the CPU 44a determines that there is an obstacle to be avoided. Judge that it does not exist. When the CPU 44a determines that there is no obstacle to avoid (No in S118), the movement target position setting unit 64b sets the movement target position 78 at the tracking angle θ based on the target movement direction P of the target 74 ( S120). When the movement target position 78 is set, the straight traveling speed calculating unit 66a calculates the tracking straight traveling speed, and the turning speed calculating unit 66b calculates the tracking turning speed (S122). Then, the traveling control unit 66 sets the direction of the caster 28 by the rudder angle setting unit 66c so that the wheelchair 10 moves to the movement target position, and drives the actuator 24a (motor) by the motor control unit 66e, The wheelchair 10 is moved to the movement target position (S124).

When the CPU 44a has confirmed that the movement to the movement target position in the current control cycle has been completed based on the relative position with respect to the target 74 after movement and the tracking angle θ based on the target movement direction P of the target 74. (Yes in S126), it is detected whether the completion condition of the tracking travel mode is satisfied (S128). For example, when the driving mode is a mode other than the tracking driving mode or when the movement of the target 74 cannot be confirmed for a predetermined period or longer (when the target 74 has stopped for, for example, 60 seconds), the CPU 44a completes the tracking driving mode. It is determined that the condition is satisfied (Yes in S128). The CPU 44a causes the display control unit 68 to display the end of the tracking travel mode (S130), and once ends this flow. In S128, when it is not possible to detect that the tracking travel mode end condition is satisfied (No in S128), the CPU 44a proceeds to S108 and executes the subsequent processing. As a result, as long as the target 74 continues to move, the wheelchair 10 can track the target 74. If it is not possible to confirm in S126 that the movement to the movement target position in the current control cycle has been completed (No in S126), the CPU 44a returns to S124 and continues to move to the movement target position.

In S118, when the CPU 44a determines that there are obstacles to avoid around the wheelchair 10 (Yes in S118), the movement target position setting unit 64b determines that there are obstacles to avoid as an area where the wheelchair 10 exists. The avoidance position is set in an area different from the existing area (S132). This avoidance position is set, for example, in a region on the side where the number of obstacles to be avoided with the target 74 interposed therebetween is smaller. For example, as shown in FIGS. 13 and 14, when there is an obstacle 80a (80b) to be avoided on the left side across the target 74, the wheelchair 10 is avoided on the right side (reverse side) of the target 74. The tracking movement is executed based on the position. In the case of the present embodiment, the avoidance trajectory is different for moving to the avoidance position 82 based on the direction in which the obstacle to be avoided approaches. For example, FIG. 13 shows a case where the pedestrian 80b approaches from the front of the wheelchair 10 as an obstacle at the approach speed VQ. When the pedestrian 80b approaches from the front of the wheelchair 10 as indicated by a dotted line (Yes in S134), the movement target position setting unit 64b moves backward while avoiding the wheelchair 10 moving away from the pedestrian 80b. Is selected (S136). For example, when the second relative distance L between the pedestrian 80b and the wheelchair 10 is equal to or less than a predetermined distance threshold (for example, 3 m or less), the wheelchair 10 passes the retreat avoidance track and avoids the opposite side across the target 74. Move to position 82. Further, when the second relative distance L between the pedestrian 80b and the wheelchair 10 is reduced, the predicted contact time until the wheelchair 10 having the straight traveling speed VM contacts the pedestrian 80b having the approach speed VQ is equal to or less than a predetermined time threshold. When it becomes (for example, 5 seconds or less), the wheelchair 10 moves to the avoidance position 82 on the opposite side across the target 74 through the retreat avoidance track retreating away from the pedestrian 80b.

FIG. 14 shows a case where the pedestrian 80a approaches from the rear of the wheelchair 10 as an obstacle at the approach speed VQ. When the pedestrian 80a approaches from the rear of the wheelchair 10 as indicated by a dotted line (No in S134), the movement target position setting unit 64b moves forward while avoiding the movement of the wheelchair 10 away from the pedestrian 80a. Is selected (S138). For example, when the second relative distance L between the pedestrian 80a and the wheelchair 10 is equal to or less than a predetermined distance threshold (for example, 3 m or less), the wheelchair 10 passes the forward avoidance track away from the pedestrian 80a and sandwiches the target 74. To move to the opposite avoidance position 82. Further, when the second relative distance L between the pedestrian 80a and the wheelchair 10 is reduced, the predicted contact time until the wheelchair 10 having the straight traveling speed VM and the pedestrian 80a having the approach speed VQ come into contact with each other is equal to or less than a predetermined time threshold. When it becomes (for example, 5 seconds or less), the wheelchair 10 moves to the avoidance position 82 on the opposite side across the target 74 through the forward avoidance track away from the pedestrian 80a.

When the avoidance position 82 and the avoidance trajectory are determined, the straight traveling speed calculating unit 66a calculates the avoiding straight traveling speed of the wheelchair 10 for moving to the avoiding position 82, and the turning speed calculating unit 66b calculates the avoiding turning speed (S140). . Then, the traveling control unit 66 performs avoidance movement of the wheelchair 10 to the avoidance position 82 (S142). This avoidance movement may be linearly moved from the current position of the wheelchair 10 to the avoidance position 82, or along the orbit circle (first orbit circle: radius R1 or second orbit circle: radius R2). It may be moved. When avoiding by moving the wheelchair 10 linearly, the travel time can be shortened and the pedestrian 80a and the pedestrian 80b can be quickly separated. On the other hand, when avoiding movement along the first or second circle, the avoidance movement is performed while the relative distance between the wheelchair 10 and the target 74 is kept constant, so that the wheelchair 10 and the target 74 are more than usual. Therefore, even if the avoidance movement suddenly starts, it is possible to make it difficult for the user and the target 74 to feel uncomfortable. Then, when the avoidance movement of the wheelchair 10 to the avoidance position 82 is completed (Yes in S144), the CPU 44a shifts to S120 and executes the subsequent processing to perform the tracking control of the target 74 based on the avoidance position 82. To implement. In S144, when the avoidance movement is not completed (No in S144), the avoidance movement in S142 is continued to reach the avoidance position 82.

In S100, when it is not the self-running mode and it is not detected that the tracking running mode is selected (No in S100), the display control unit 68 outputs a control signal indicating that it is the normal running mode to the output unit 72. And display such as “during normal driving mode control” on the display device 42a (S146). Then, the traveling control unit 66 executes the stick operation driving process according to the operation state of the operation unit 36 (S148). For example, the straight traveling speed calculation unit 66a calculates the straight traveling speed according to the amount of tilting of the joystick, and the turning speed calculating unit 66b calculates the turning speed according to the direction of tilting the joystick. Then, the rudder angle setting unit 66c sets the rudder angle of the caster 28 and drives the actuator 30a of the steering system 30 by a predetermined amount. Further, the motor control unit 66e rotates the actuator 24a (motor) of the drive system 24 at a predetermined speed, and moves the wheelchair 10 in the direction instructed by the joystick.

The CPU 44a continues the stick operation driving process until the stop process condition in the normal travel mode is satisfied (No in S150). The conditions for the stop process in the normal travel mode can be considered to be satisfied, for example, when a predetermined period (for example, 30 seconds) has elapsed after the joystick is returned to the neutral position. When the condition for the stop process in the normal travel mode is satisfied (Yes in S150), the CPU 44a determines that the end condition for the normal travel mode is satisfied, and causes the display control unit 68 to display the end of the normal travel mode (S152). ) This flow is finished once.

As described above, according to the moving body tracking system 100 of the present embodiment, the wheelchair 10 maintains the first relative position from the target 74 and also has the position of the tracking angle θ based on the target moving direction P of the target 74 (for example, The target position is always set at the left and right positions of the target 74, and the target 74 moves. As a result, in order to track the wheelchair 10 to the target 74, it is not necessary to estimate a complicated movement path of the target 74, the calculation load for tracking can be reduced, and smooth tracking (following) operation at low cost is possible. Can be realized.

In the above-described embodiment, the wheelchair 10 is shown as an example of the moving body. However, the present invention is not limited to this, and a moving vehicle that rides in a sitting posture or a standing posture may be used as a moving means for a healthy person. Similar effects can be obtained. Moreover, the vehicle which moves other than a human may be sufficient. For example, it may be an unmanned vehicle or a robot for luggage transportation or animal transportation. In this case, the traveling mode may be only the tracking traveling mode. A plurality of moving bodies may be run. For example, the leading mobile body may track the target 74, and the subsequent mobile body may regard the preceding mobile body as the tracking target body and track it, and the same effect can be obtained.

In the above-described embodiment, an example in which the degree of congestion of the obstacle is determined by the surrounding situation recognition unit 64c based on the acquisition result of the acquisition unit 58 has been described. In another embodiment, the CPU 44a may acquire the degree of congestion and the position of an obstacle (pedestrian 80) from the infrastructure around the moving object (wheelchair 10), or an area where the moving object (wheelchair 10) exists. The degree of congestion (for example, the degree of congestion by time zone) may be acquired with reference to the past congestion degree data, and reflected in the tracking control.

In the above-described embodiment, the laser sensor 38 is shown as an example of an information acquisition unit that acquires information indicating the positional relationship between objects around the moving body (wheelchair 10). , And a relative distance from the object, etc.) can be appropriately changed. For example, an image may be acquired by an imaging device (stereo camera or the like), and information indicating the positional relationship of surrounding objects may be acquired by performing image processing on the image, which is the same as when the laser sensor 38 is used. You can get an effect.

Although embodiments and modifications of the present invention have been described, these embodiments and modifications are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 ... Wheelchair, 22 ... Drive wheel, 24 ... Drive system, 26 ... Brake system, 28 ... Caster, 30 ... Steering system, 32 ... Battery system, 36 ... Operation part, 38 ... Laser sensor, 42 ... Monitor apparatus, 44 ... ECU, 60 ... target specifying unit, 62 ... obstacle specifying unit, 64 ... target setting unit, 64a ... trajectory circle setting unit, 64b ... movement target position setting unit, 64c ... peripheral situation recognition unit, 66 ... travel control unit, 66a ... straight speed calculation unit, 66d ... battery control unit, 66e ... motor control unit, 68 ... display control unit, 72 ... output unit, 74 ... target, 76a, 76b ... concentric circle, 78 ... target position for movement, 80 ... pedestrian, 82 ... avoidance position, 100 ... moving body tracking system, P ... target movement direction, θ ... tracking angle.

Claims

A target identifying unit that identifies a tracking target object that the mobile body tracks;
Based on the acquisition result of the information acquisition unit that acquires information indicating the positional relationship of objects around the moving body, at least the relative distance between the moving body and the tracking target object, and the moving direction of the tracking target object, An acquisition unit to acquire;
A target that is located on a direction deviated from the movement direction by a predetermined angle with respect to the movement direction of the tracking target object, and that sets the movement target position of the moving object at a first relative distance from the tracking target object A setting section;
A control unit for controlling the moving body to move to the movement target position;
A moving body tracking control device.
2. The moving body tracking control device according to claim 1, wherein the target setting unit sets the moving target position on a circular orbit whose center is the position of the tracking target object and whose radius is defined by the first relative distance. .
The said target setting part sets the said movement target position to the area | region except the predetermined back area | region containing the reverse vector of the said moving direction from the area | region of the side and the back of the said tracking object. The moving body tracking control device described.
The moving object tracking control device according to any one of claims 1 to 3, wherein the target setting unit changes the first relative distance according to a surrounding situation of the moving object.
The acquisition unit is configured to reduce the second relative distance between the obstacle and the moving body that is present in the periphery of the moving body included in the acquisition result of the information acquisition unit or the second relative distance is reduced. Get the predicted contact time to contact the moving body,
When the second relative distance is less than or equal to a predetermined distance threshold or when the predicted contact time is less than or equal to a predetermined time threshold, the target setting unit moves the target position from the tracking target to the first The moving body tracking control apparatus according to any one of claims 1 to 4, wherein the moving body tracking control apparatus is set to a position closer than one relative distance.
The acquisition unit is configured to reduce the second relative distance between the obstacle and the moving body that is present in the periphery of the moving body included in the acquisition result of the information acquisition unit or the second relative distance is reduced. Get the predicted contact time to contact the moving body,
When the second relative distance is equal to or smaller than a predetermined distance threshold or when the predicted contact time is equal to or smaller than a predetermined time threshold, the target setting unit sandwiches the tracking target object and Set the movement target position on the opposite side,
The said control part controls the movement so that it may move to the said movement target position of the said opposite side through the track | orbit which the said mobile body leaves | separates from the said obstacle. Body tracking control device.