JPH11231936A - Unmanned vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an unmanned vehicle capable of stopping without being deviated from a determined traveling locus at the time of emergency stop and surely stopping in a shorter braking distance. SOLUTION: In the case of immediately executing the emergency stop of an unmanned vehicle concerned based on a prescribed emergency stop command, the unmanned vehicle is urgently stopped while controlling the direction of the vehicle by a traveling control part 31 and a steering driving part 33. Thereby the unmanned vehicle can be stopped at the time of emergent stop without being deviated from a determined traveling locus. The unmanned vehicle is urgently stopped by decelerating a motor 35 for driving the unmanned vehicle at a prescribed deceleration ratio by the control part 31 and a motor driving part 32. When a speed pattern is set up so as to obtain a large deceleration ratio as possible within a range not exceeding the allowable torque of the motor 35, the unmanned vehicle can be stopped in an extremely short braking distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unmanned vehicle capable of making an emergency stop based on a predetermined emergency stop command such as pressing an emergency stop button.

[0002]

2. Description of the Related Art FIG. 7 shows a schematic configuration of a control system of a conventional general unmanned vehicle Z0. As shown in the drawing, the conventional unmanned vehicle Z0 has a motor driving unit 32 for driving a motor 35.
A steering drive unit 33 for driving a steering unit 36 for steering the vehicle body; and a brake drive unit 34 for opening and closing the brake 37.
A travel control unit 31 that controls the travel of the unmanned vehicle Z0 by outputting control signals to the motor drive unit 32, the steering drive unit 33, and the brake drive unit 34;
Upon detection of a predetermined emergency stop command, the motor drive unit 3
2, the steering drive unit 33 and the brake drive unit 34
And an emergency stop command detecting section 38 for controlling the unmanned vehicle Z0 to perform an emergency stop. The brake 37
The main purpose is to maintain the stopped state of the vehicle body. Next, a control procedure of the unmanned vehicle Z0 will be described with reference to FIG. To start traveling, first, the traveling control unit 31 issues a servo ON command to the motor driving unit 32 and the steering driving unit 33 (step S31), and opens a brake to the brake driving unit 34. A (release) command is issued (step S32). Thereby, unmanned vehicle Z0
Is ready to run. Thereafter, the travel control unit 31
When the speed command and the torque command are given to the motor drive unit 32 and the direction command is given to the steering drive unit 33, the traveling control is performed until the unmanned vehicle Z0 reaches the target point (step S33 → S34 → S35 →
S33 →). When the unmanned vehicle Z0 arrives at the target point and the traveling control ends (step S35), the traveling control unit 31 issues a brake closing (operation) command to the brake driving unit 34 (step S36). A servo OFF command is issued to the motor drive unit 32 and the steering drive unit 33, and the traveling ends (step S37). If, for example, an emergency stop button provided on the vehicle body is pressed during traveling of the unmanned vehicle Z0, the emergency stop command detection unit 38 detects the emergency stop command from the emergency stop button. (Step S34) Immediately, a brake closing command is sent to the brake drive unit 34 (Step S36), and the servo O is sent to the motor drive unit 32 and the steering drive unit 33.
An FF command is issued (step S37), and the vehicle body is suddenly stopped only by the frictional force of the brake 37.

[0003]

However, in the above-described emergency stop method, the servo is turned off upon detection of the emergency stop signal, and the braking operation is performed in a state in which the traveling control of the vehicle body, especially the direction control is not performed. Therefore, there is a possibility that the vehicle body may deviate from the predetermined traveling locus until the vehicle completely stops. This is particularly likely when an emergency stop is performed during curve running or high-speed running, and there is a risk of colliding with other unmanned vehicles or walls, which is extremely dangerous. As described above, the brake 37 is mainly intended to maintain the stopped state of the vehicle body, and does not have sufficient ability for braking the vehicle body during traveling. In such a case, there is a problem that the braking distance is extended and sufficient safety cannot be secured. Although it is conceivable to use a brake having a high braking capacity, it is contrary to the demand for downsizing the device. The present invention has been made in view of the above circumstances, and a first object of the present invention is to provide an unmanned vehicle that can be stopped without departing from a traveling locus determined at the time of an emergency stop, and can reliably stop at a shorter braking distance. A second object is to provide an unmanned vehicle.

[0004]

In order to achieve the above object, the present invention relates to an unmanned vehicle having emergency stop control means for immediately stopping the unmanned vehicle based on a predetermined emergency stop command. The control means is configured to perform an emergency stop of the unmanned vehicle while controlling the direction of the vehicle body, and is configured as an unmanned vehicle. Further, if the emergency stop control means is configured to perform an emergency stop of the unmanned vehicle by causing the drive means for driving the unmanned vehicle to be decelerated at a predetermined deceleration rate, for example, the speed pattern of the motor By setting the deceleration rate to be as large as possible within a range that does not exceed the allowable torque, it becomes possible to stop the unmanned vehicle at an extremely short braking distance. In this case, if the brake is operated after a lapse of a predetermined time from the detection of the predetermined emergency stop command, the worst accident due to runaway of the unmanned vehicle can be prevented even if the deceleration running control is abnormal. . If it is possible to mount a brake having sufficient braking ability, the brake may be used for emergency stop.

[0005]

In the unmanned vehicle according to the present invention, the direction control is performed until the vehicle stops completely after detecting the emergency stop command.
Even when traveling on a curve or traveling at high speed, the vehicle can be safely stopped without deviating from a predetermined traveling locus. Further, if the unmanned vehicle is configured to be emergency-stopped by being decelerated at a predetermined deceleration rate, for example, the speed pattern may be set so as to be as large as possible within a range not exceeding the allowable torque of the motor. Thus, the unmanned vehicle can be stopped at an extremely short braking distance. that time,
Further, by closing the brake after a lapse of a predetermined time after the detection of the emergency stop command, even if an abnormality occurs in the control of the deceleration drive, the worst accident due to the runaway of the unmanned vehicle can be prevented. When an emergency stop command is detected by using a brake, when an emergency stop command is detected, the brake is immediately closed and direction control is performed until the brake is completely stopped. Therefore, the vehicle can be safely stopped without deviating from a predetermined traveling locus even when traveling on a curve or traveling at high speed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and examples of the present invention will be described below with reference to the accompanying drawings to facilitate understanding of the present invention. The following embodiments and examples are mere examples embodying the present invention, and do not limit the technical scope of the present invention. Here, FIG. 1 is a block diagram illustrating a schematic configuration of a control system of the unmanned vehicle Z1 according to the embodiment of the present invention, FIG. 2 is a flowchart illustrating a control procedure of the unmanned vehicle Z1, and FIG. FIG. 4 is a schematic diagram showing an arrangement of drive wheels, FIG. 4 is a block diagram showing a schematic configuration of a control system of the unmanned vehicle Z2 according to the embodiment of the present invention, FIG. 5 is a flowchart showing a control procedure of the unmanned vehicle Z2, and FIG. It is explanatory drawing which shows arrangement | positioning of the drive wheel of the said unmanned vehicle Z2, and definition of direction (phi) of a vehicle body. In the present embodiment, an example is shown in which the present invention is applied to an unmanned vehicle Z1 (see FIG. 3) in which a total of three wheels W1, W2 and W3 are arranged in the center of the right side of the vehicle body. . Each of the wheels W1 to W3 can be independently speed-controlled and direction-controlled. Each of the above wheels W1 to W3
Are connected to a motor 35 (an example of a driving unit) and a steering unit 36 shown in FIG.
5, a driving force in the traveling direction is given, and the steering unit 3
6 changes the steering angle. The control system of the unmanned vehicle Z1 according to the present embodiment, as shown in FIG.
Motor driving unit 32 that drives a motor 35 for rotating the motor 3
A steering drive unit 33 that drives a steering unit 36 that changes the directions (steering angles) of the wheels W1 to W3; a brake drive unit 34 that switches the opening and closing of a brake 37; the motor drive unit 32; By outputting a control signal to the unit 33 and the brake driving unit 34, the unmanned vehicle Z
A traveling control unit 31 for controlling traveling of the vehicle 1; an emergency stop instruction detecting unit 1 for outputting a deceleration control instruction to the traveling control means 31 upon detection of a predetermined emergency stop instruction; The emergency stop is operated by a command from the emergency stop command detection unit 1 and controls the motor drive unit 32, the steering drive unit 33, and the brake drive unit 34 to stop the unmanned vehicle Z1 in an emergency when the time is up. And a timer 2. Here, the emergency stop command detecting unit 1, the traveling control unit 31, the motor driving unit 32, the steering driving unit 33, and the brake driving unit 3
4 is an example of emergency stop control means. The main purpose of the brake 37 is to maintain the stopped state of the vehicle body.

Next, the control procedure of the unmanned vehicle Z1 will be described with reference to FIG. When starting traveling, first, the traveling control unit 31 issues a servo ON command to the motor driving unit 32 and the steering driving unit 33 (step S1), and opens a brake to the brake driving unit 34 (step S1). Release) command is issued (step S2). Thus, the unmanned vehicle Z1 is in a state where it can travel. After that, the traveling control unit 31 gives a speed command and a torque command to the motor driving unit 32 and a direction command to the steering driving unit 33, thereby controlling the traveling until the unmanned vehicle Z1 reaches the target point. (Steps S3 → S4 → S5 → S3 →...). When the unmanned vehicle Z1 arrives at the target point and the traveling control ends (step S5), the traveling control unit 31 issues a brake closing (operation) command to the brake driving unit 34 (step S6). A servo OFF command is issued to the motor drive unit 32 and the steering drive unit 33, and the traveling ends (step S7).

If the emergency stop button provided on the vehicle body is pressed while the unmanned vehicle Z1 is traveling, the emergency stop command detecting unit 1 sends the emergency stop command from the emergency stop button. (Example of a predetermined emergency stop command) is detected (step S4), and a deceleration control command is immediately output to the traveling control unit 31 and the emergency stop timer 2 is operated. The travel control unit 31 receives the deceleration control command from the emergency stop command detection unit 1 and generates a speed pattern such that the deceleration rate is as large as possible within a range that does not exceed the allowable torque of the motor 35. A speed command is output to the drive unit 32, and a direction command is output to the steering drive unit 33 so as to continue traveling on the determined travel locus (step S8). As a result, the unmanned vehicle Z1 can be stopped at an extremely short braking distance without deviating from a predetermined traveling locus. When the time preset in the emergency stop timer 2 has elapsed (step S9), the emergency stop timer 2 issues a brake closing command to the brake driving unit 34 (step S9).
6) Output a servo OFF command to the motor drive unit 32 and the steering drive unit 33 (step S7). Here, the set time of the emergency stop timer 2 is set, for example, to a time required for the unmanned vehicle Z1 to stop at the emergency deceleration rate while traveling at the maximum speed. As a result, if there is no abnormality in the deceleration control at the time of emergency stop by the traveling control unit 31, the brake is closed and the servo is OFF with the unmanned vehicle Z1 completely stopped. By providing such an emergency stop timer 2, even if there is an abnormality in the deceleration running control in step A8, step S6
Since the stop operation is performed in S7, the worst accident due to runaway of the unmanned vehicle Z1 can be prevented. As explained above,
The unmanned vehicle Z1 according to the present embodiment, even after detecting the emergency stop command, performs direction control by the steering drive unit 33 until it is completely stopped, so that it is running on curves or running at high speed. The vehicle can be safely stopped without deviating from the predetermined traveling locus.

Further, instead of the brake, the traveling control unit 31
For example, the unmanned vehicle Z1 is stopped at an extremely short braking distance by setting the speed pattern so as to have a deceleration rate as large as possible within a range not exceeding the allowable torque of the motor 35. Becomes possible. Further, by detecting the emergency stop command by the emergency stop timer 2 and closing the brake 37 after a lapse of a predetermined time, even if the deceleration traveling control by the traveling control unit 31 is abnormal, the unmanned vehicle Z1 Can prevent the worst accidents caused by runaway.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the unmanned vehicle Z1 according to the above embodiment, the deceleration control by the traveling control unit 31 is used as a method of braking the vehicle body at the time of an emergency stop, but a brake having sufficient braking ability can be mounted. In such a case, the emergency braking may be performed using the brake. in this case,
When the emergency stop command is detected by the emergency stop command detection unit 1, the travel control unit 31 immediately outputs a brake close command to the brake drive unit 34, and simultaneously outputs the brake drive command to the steering drive unit 3.
A direction command is output to the control unit 3 so as to continue traveling on the determined traveling locus. Therefore, even in this case, since the direction control by the steering drive unit 33 is performed until the vehicle completely stops, the vehicle can be safely stopped without deviating from a predetermined traveling locus even during curve running or running at high speed. It goes without saying that the deceleration control by the traveling control unit 31 and the brake may be used in combination. Also,
The unmanned vehicle to which the present invention can be applied is not limited to a three-wheel drive steering type unmanned vehicle as shown in FIG. 3, but may be a two-wheel speed difference type unmanned vehicle that changes direction according to the speed difference between two wheels.
It goes without saying that it can be applied to all types of unmanned vehicles. Here, as an example, an example in which the present invention is applied to a two-wheel speed difference type unmanned vehicle Z2 will be described. In this example, a brake is used for braking during an emergency stop. Unmanned car Z
2, drive wheels Wa, W on the left and right sides of the vehicle body as shown in FIG.
b is a two-wheel speed difference type unmanned vehicle arranged in parallel.
The speed of the wheels Wa and Wb can be independently controlled, and the direction control of the vehicle body is performed based on the speed difference between the two wheels. FIG. 4 shows a schematic configuration of a control system of the unmanned vehicle Z2. As shown in the figure, the unmanned vehicle Z2 includes a left wheel motor 2 connected to two left and right driving wheels Wa and Wb, respectively.
4a, a motor drive unit 22 for driving the right wheel motor 24b, a vehicle body posture detecting unit 11 for detecting a vehicle body direction (φ shown in FIG. 6), and a vehicle body direction obtained by the vehicle body posture detecting unit 11. A brake switching drive unit 12 for switching between opening and closing of a left wheel brake 25a and a right wheel brake 25b respectively connected to the two left and right drive wheels Wa and Wb based on a deviation from a desired traveling direction; And a travel control unit 2 that controls the travel of the unmanned vehicle Z2 by outputting a control signal to the brake switching drive unit 12.
1 and an emergency stop command detecting unit 26 that controls the motor drive unit 22 and the brake switching drive unit 12 to stop the unmanned vehicle Z2 by detecting a predetermined emergency stop command. Here, the emergency stop command detection unit 2
6, the travel control unit 21, the motor drive unit 22, the vehicle body posture detection unit 11, and the brake switching drive unit 12 are examples of emergency stop control means. Note that various known means such as a gyro can be used as the vehicle body posture detecting unit 11.

Next, a control procedure of the unmanned vehicle Z2 will be described with reference to FIG. Note that the traveling control during normal traveling is the same as steps S31 to S35 shown in FIG. 8, and therefore, only the control procedure when an emergency stop command is detected in step S34 in FIG. 8 will be described here.
For example, when an emergency stop button provided on the vehicle body is pressed during traveling of the unmanned vehicle Z2, the emergency stop command detection unit 26 outputs an emergency stop command from the emergency stop button (a predetermined emergency stop command). Is detected (step S in FIG. 8).
34) The servo O is immediately applied to the motor drive unit 22.
An FF command is issued (step S11). Then, the following steps S12 to S18 are repeatedly performed until the vehicle body completely stops.

First, the orientation φ of the vehicle body is detected by the vehicle body posture detecting section 11 (step S12). Then, a deviation between the direction φ of the vehicle body and a desired traveling direction (here, the straight traveling direction) is obtained by the brake switching drive unit 12 (step S13). If the deviation is 0, both the left wheel brake 25a and the right wheel brake 25b are closed by the brake switching drive unit 12 (step S1).
4). If the deviation is a positive value, that is, if the vehicle body is displaced leftward from the straight traveling direction, the left wheel brake 2
5a is opened and the right wheel brake 25b is closed (step S16), and if the above deviation is a negative value, that is, if the vehicle body is displaced rightward from the straight traveling direction, the left wheel brake 2b is closed.
5a is closed and the right wheel brake 25b is opened (step S17). By performing the switching control of the left and right brakes as described above, the direction of the vehicle body is corrected so as to approach a desired traveling direction. That is, the vehicle body always travels along a desired travel locus until it stops. The processing after step S12 is repeatedly performed until the vehicle body completely stops (step S18 → S12 → ...). When the vehicle completely stops, both the left wheel brake 25a and the right wheel brake 25b are closed (step S19), and the emergency stop processing is completed. As described above, the unmanned vehicle Z2 according to the present embodiment
Is the vehicle body orientation φ detected by the vehicle body posture detection unit 11 even after the emergency stop command is detected and the servo is turned off.
Based on the deviation between the vehicle and the desired traveling direction, the switching control of opening and closing the left and right brakes is performed so as to correct the direction of the vehicle body in a direction to reduce the deviation. It can be safely stopped.

[0013]

As described above, the present invention relates to an unmanned vehicle provided with emergency stop control means for immediately stopping the unmanned vehicle based on a predetermined emergency stop command. It is configured to perform an emergency stop of the unmanned vehicle while controlling the direction of the vehicle, so that the unmanned vehicle is configured to perform a predetermined traveling even when traveling on a curve or traveling at a high speed. It can stop safely without deviating from the trajectory. Further, if the emergency stop control means is configured to perform an emergency stop of the unmanned vehicle by causing the drive means for driving the unmanned vehicle to be decelerated at a predetermined deceleration rate, for example, the speed pattern of the motor By setting the deceleration rate to be as large as possible within a range that does not exceed the allowable torque, it becomes possible to stop the unmanned vehicle at an extremely short braking distance. In this case, if the brake is operated after a lapse of a predetermined time from the detection of the predetermined emergency stop command, the worst accident due to runaway of the unmanned vehicle can be prevented even if the deceleration running control is abnormal. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a control system of an unmanned vehicle Z1 according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a control procedure of the unmanned vehicle Z1.

FIG. 3 is a schematic diagram showing an arrangement of drive wheels of the unmanned vehicle Z1.

FIG. 4 is a block diagram showing a schematic configuration of a control system of the unmanned vehicle Z2 according to the embodiment of the present invention.

FIG. 5 is a flowchart showing a control procedure of the unmanned vehicle Z2.

FIG. 6 is an explanatory diagram showing an arrangement of drive wheels of the unmanned vehicle Z2 and a definition of a body direction φ.

FIG. 7 is a block diagram showing a schematic configuration of a control system of a conventional unmanned vehicle Z0.

FIG. 8 is a flowchart showing a control procedure of the unmanned vehicle Z0.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Emergency stop command detection part 2 ... Emergency stop timer 31 ... Traveling control part 32 ... Motor drive part 33 ... Steering drive part 34 ... Brake drive part

Claims (4)

[Claims] 1. An unmanned vehicle provided with emergency stop control means for immediately stopping the unmanned vehicle based on a predetermined emergency stop command, wherein the emergency stop control means controls the unmanned vehicle while controlling the direction of the vehicle body. An unmanned vehicle characterized by being configured to make an emergency stop. 2. The emergency stop control means according to claim 1, wherein said emergency stop control means performs an emergency stop of said unmanned vehicle by causing said driving means for driving said unmanned vehicle to decelerate at a predetermined deceleration rate. The unmanned car described. 3. The unmanned vehicle according to claim 2, wherein the brake is operated after a predetermined time has passed since the detection of the predetermined emergency stop command. 4. The unmanned vehicle according to claim 1, wherein said emergency stop control means is configured to stop said unmanned vehicle by a brake.