JPH0981241A - Control method for unmanned vehicles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automated guided vehicle control method by which the succeeding operation will not be affected even when a vehicle body is stopped before the completion of rotational traveling. SOLUTION: In an automated guided vehicle 10, a control part 35 individually detects the locus distances of driving wheels 36A, 36B arranged in parallel in the traveling width direction of a vehicle body 31 by respective counters 33A, 33B and individually controls the rotation of the wheels 36A, 36B while monitoring the values of the counters 33A, 33B. The control part 35 controls the rotation of either one of the wheels 36A, 36B so that the values of the counters 33A, 33B are equal to each other at the time of stopping the body 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method for an unmanned vehicle, and more specifically, it relates to an unmanned vehicle that does not affect the next operation even if the vehicle body is stopped before the completion of turning traveling. It relates to a control method.

[0002]

2. Description of the Related Art In recent years, unmanned vehicles have been introduced to clean passages and convey cargo in buildings, for example. In the unmanned vehicle 30 shown in FIG. 3, the vehicle body 31 is provided with a traveling means 32, a counter 33, a distance measuring means 34, and a controller 35 in order to travel along the wall surface 41 in the passage 40 inside the building.

The traveling means 32 includes a pair of drive wheels 36A and 36B arranged in parallel in the traveling width direction of the vehicle body 31, and the vehicle body 3
A pair of driven wheels 37A, 3 arranged in the longitudinal direction of travel
7B and a pair of motors 38A and 38B for individually driving the drive wheels 36A and 36B. Counter 33
(33A, 33B) are rotary encoders attached to the rotary shafts of the motors 38A, 38B, respectively, and individually detect the rotational speeds of the drive wheels 36A, 36B having the same diameter. These counters 33A, 33B
When the locus distances of the drive wheels 36A and 36B are the same, the counted values are equal to each other.

An ultrasonic distance sensor is used as the distance measuring means 34, and a plurality of ultrasonic distance sensors are provided around the vehicle body 31. These distance measuring means 34 measure the distance from the vehicle body 31 to the nearest measurement object such as a person or an obstacle located on the wall surface 41 or the passage 40, and output the distance measurement value to the control unit 35. For example, a CPU is used as the control unit 35, and the vehicle body 31 is caused to travel straight by controlling the rotation speeds of the motors 32C so that the values of the counters 33A and 33B become equal to each other.

Such an unmanned traveling vehicle 30 has a distance measuring means 3
When the control unit 35 determines that the vehicle body 31 deviates from the traveling track C based on the distance measurement value of 4 (state of the solid line in the figure), the vehicle body 31 travels along the traveling track C ( The position indicated by the chain double-dashed line A in the figure) is corrected so that the vehicle body 31 travels so as to draw a substantially S-shaped travel locus. In the case of this figure, the position is corrected by setting the value of the counter 33A to the counter 33.
By rotating the motor 38B at a higher speed than the motor 38A so that the value becomes larger than the value of B by a predetermined value, the vehicle body 3
In order to make the values of the counters 33A and 33B equal to each other after the completion of the first-half turn and the first-half turn in which 1 is rotated counterclockwise, the motor 38B is more effective than the motor 38B.
It is performed by the latter half turn in which the vehicle body 31 is rotated clockwise by rotating A at a high speed.

[0006]

By the way, the unmanned traveling vehicle 30 has a vehicle body 31 in order to avoid contact with the object to be measured.
When the distance measurement value becomes less than or equal to a predetermined value due to the relative proximity between the object and the measurement object, the control unit 35 stops the vehicle body 31 and stops even before the position correction is completed, for example. The previous running condition is interrupted.
In this case, since the unmanned traveling vehicle 30 stops in the middle of the first half turn or the second half turn constituting the position correction, the counters 33A and 33B have different values and the vehicle body 31 tilts with respect to the traveling track C. State (see the chain double-dashed line B in the figure) and the vehicle body 31 with respect to the traveling track C
Is not corrected. Therefore, the unmanned traveling vehicle 30 may contact the wall surface 41 when the vehicle body 31 is rotated 180 degrees from this state (see the broken line A in the drawing) and then moved forward (see the broken line B in the drawing).

This problem is caused when the vehicle body 31 is stopped before the direction change for turning the vehicle body by a predetermined distance is completed in order to correct or change the traveling direction of the vehicle body 31, or
Alternatively, it occurs even when a person passes near the vehicle body 31 before the position correction and the direction change are completed, and a solution is desired. The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide an unmanned vehicle that does not affect the subsequent operation even if the vehicle body is stopped before the completion of turning traveling. It is to provide a control method.

[0008]

DISCLOSURE OF THE INVENTION The present invention was devised by the present inventor paying attention to the fact that when the vehicle body is stopped before the completion of turning traveling, the values of the respective counters are different from each other. Is. Therefore, in order to achieve the above object,
According to a first aspect of the present invention, a pair of driving wheels arranged in parallel in a traveling width direction of a vehicle body, a pair of counters individually detecting a trajectory distance of each driving wheel, and a value of each counter In a control method for an unmanned vehicle having a control unit for individually controlling the rotation of each drive wheel while monitoring the above, when the vehicle body is stopped, the control unit controls the values of the counters to be equal to each other. One of the driving wheels is controlled to rotate.

In this case, in order to make the values of the counters equal, the drive wheel having the smaller counter value among the drive wheels may be driven in the forward direction, and the drive wheel having the larger counter value may be driven in the reverse direction. May be. Such claim 1 of the present invention
In the invention described in (1), for example, when the vehicle body stops before the turning travel for completing the traveling track is completed, the values of the counters are different from each other, so that the values of the counters are equal to each other. By controlling the rotation of each drive wheel, at least the vehicle body can be made parallel to the running track. Then, if one of the drive wheels is rotationally controlled, the vehicle body turns around the other drive wheel, so that the operation for making the vehicle body parallel to the running track can be minimized. For example, it is possible to reduce the risk of contact with the measurement target.

Further, the invention according to claim 2 of the present invention is characterized in that the control section drives the drive wheel having a smaller value of the counter among the drive wheels in the normal direction. Generally, a rotary encoder used as a counter has a characteristic that when a drive wheel rotates from a stopped state, it counts as a positive number regardless of whether the rotation direction is forward or reverse. Therefore, in order to make the values of the counters equal, if the driving wheels with large counter values are reversed from the stopped state, the values of the counters are added, and therefore it is necessary to determine that the values of the counters have become equal. In addition, separate processing is required in the control unit. On the other hand, in the invention described in claim 2 of the present invention, since the values of the respective counters are made equal by rotating the drive wheels having the small counter values in the forward direction, the above-described separate processing is not required,
The processing of the control unit can be simplified.

According to a third aspect of the present invention, when the control unit detects a wall surface in front of the vehicle body and stops the vehicle body, the counters have the same value. The control unit controls the rotation of one of the drive wheels, and then turns the vehicle body by 180 degrees, thereby achieving the above object.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiments described below,
The members already described with reference to FIG. 3 are denoted by the same reference numerals in the drawing to simplify or omit the description. FIG. 1 shows an embodiment according to the present invention. In this figure, in the unmanned vehicle 10, the control unit 35 stops the vehicle body 31 based on the distance measurement value and corrects the position before the position correction for moving the vehicle body 31 along the traveling track C is completed. Is interrupted (see the solid line in the figure). In this case, the unmanned traveling vehicle 10 is tilted with respect to the traveling track C because the vehicle body 31 stops in the middle of the first half turn constituting the position correction, and the value of the counter 33A is equal to the value of the counter 33B. Is bigger than

In such a case, the unmanned vehicle 1 of this embodiment
In the case of 0, the control unit 35 controls the motors 38A and 38B so that the values of the counters 33A and 33B become equal. That is, the control unit 35 maintains the stopped state of the motor 38A, and activates the motor 38B in order to drive the drive wheel 36B of the counters 33A and 33B whose counted value is relatively small in the normal direction. For this reason, the vehicle body 31 is driven by the drive wheels 3 until it becomes parallel to the traveling track C.
Rotate clockwise about the grounding point of 6A by a predetermined angle (see the chain double-dashed line A in the figure). And unmanned vehicle 10
Is corrected so that the vehicle body 31 becomes parallel to the traveling track C, so that there is no possibility of contacting the wall surface 41 even if the vehicle body 31 is inverted 180 degrees and then moved forward (two points in the figure). (See chain line B).

The unmanned vehicle 10 of this embodiment operates according to the routine shown in FIG. 2 when the vehicle body 31 is stopped with the counters 33A and 33B having different values. First, in step ST1, each counter 33A, 33B
Compare the values of At step ST1, the counter 33
If the value of A (right side in the traveling direction) is larger than the value of counter 33B (left side in the traveling direction) (YES), step ST
Proceed to 2.

Then, in step ST2, the drive wheels 3
After setting 6B (the left side in the traveling direction) to rotate in the normal direction, the motor 38B (the left side in the traveling direction) is started in step ST3, and the counters 33A, 3 are started in step ST4.
Continue until the 3B values are equal. Next, step S
When the values of the counters 33A and 33B become equal at T4 (YES), the motor 38 is turned on at step ST5.
B is stopped and the vehicle body 31 is made to perform the next operation.

On the other hand, if the value of the counter 33A (right side in the traveling direction) is less than or equal to the value of the counter 33B (left side in the traveling direction) in step ST1 (NO), step ST6.
In, the values of the counters 33A and 33B are compared again. If the value of the counter 33A (right side in the advancing direction) is smaller than the value of the counter 33B (left side in the advancing direction) in step ST6 (YES), after setting the drive wheel 36A (right side in the advancing direction) to rotate normally in step ST7. , Step ST3. In step ST6, if the counters 33A and 33B have the same value (N
O), immediately causes the vehicle body 31 to perform the next operation.

According to this embodiment, when the vehicle body 31 is stopped, the control unit 31 controls the rotation of one of the drive wheels 36A and 36B so that the values of the counters 33A and 33B become equal. Before the position correction is completed, the body 31
Even if the vehicle is stopped, the vehicle body 31 is corrected so as to be parallel to the traveling start C, and even if the vehicle body 31 is turned 180 degrees and then moved forward, the state of the vehicle body 31 when stopped is not affected. Further, in this embodiment, in order to make the values of the counters 33A and 33B equal, the counter 3 having a relatively small value is used.
Since the drive wheel 36B of 3B is rotated in the normal direction, the processing of the control unit 35 is complicated even if the rotary encoders having the characteristic of counting as a positive number are used as the counters 33A and 33B regardless of the normal rotation or the reverse rotation. And the processing speed does not decrease.

It should be noted that the present invention is not limited to the above-mentioned embodiment, and for example, in order to correct or change the traveling direction of the vehicle body 31, before the direction change for rotating the vehicle body 31 by a predetermined distance is completed. When the vehicle body 31 is stopped, or before the position correction and the direction change are completed, the vehicle body 3
It is also applicable when a person passes in the vicinity of 1.

[0019]

According to the invention described in claim 1 of the present invention, even if the vehicle body is stopped before the completion of the turning traveling, the traveling direction of the vehicle body before the turning traveling can be reproduced and the subsequent operation is affected. Does not reach. Further, according to the invention described in claim 2 of the present invention, even if the rotary encoder is adopted for each counter, the processing of the control unit does not become complicated and the processing speed does not decrease. And according to the invention described in claim 3 of the present invention,
Even if the vehicle body stopped 180 degrees during the turning traveling by detecting the wall surface in the front turns, the influence of the interrupted turning traveling does not occur.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing one embodiment of the present invention.

FIG. 2 is a flowchart showing an operation routine of the embodiment.

FIG. 3 is a schematic plan view showing the operation of a conventional unmanned vehicle.

[Explanation of symbols]

 10 unmanned traveling vehicle 31 vehicle body 32A driving wheel 33 counter 35 control unit

Claims (3)

[Claims] 1. A pair of drive wheels arranged in parallel in a traveling width direction of a vehicle body, a pair of counters for individually detecting a trajectory distance of each drive wheel, and each drive while monitoring a value of each counter. In a method for controlling an unmanned vehicle having a control unit for individually controlling rotation of wheels, when the vehicle body is stopped, the control unit controls the values of the counters to be equal to each other. A method for controlling an unmanned vehicle, characterized by controlling rotation of one side. 2. The method for controlling an unmanned vehicle according to claim 1, wherein the control section drives the drive wheel having a smaller value of the counter among the drive wheels in the normal direction. 3. The control unit controls one of the drive wheels so that when the control unit detects a wall surface in front of the vehicle body and stops the vehicle body, the counters have the same value. 3. The method for controlling an unmanned vehicle according to claim 1, wherein the vehicle body is rotated 180 degrees after the rotation of the vehicle is controlled.