JPH0659726A - Running control system of unmanned vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the positional accuracy during long-distance travel by an internal sensor of an unmanned vehicle without using correction means from the outside. [Construction] An unmanned vehicle has a drive unit 12 including a traveling unit that travels on a floor and a steering unit that steers the traveling unit. The drive speed and the command angle are given from the control device 16 to the drive device 12 so that the position and attitude of the unmanned vehicle can be changed. While traveling, a distance signal from the odometer 13 and an angle signal from the gyro sensor 15 are input to the control device 16 every moment, the current position from the reference position and the amount of direction deviation are obtained, and the current position is corrected to the reference position. Controlled by.
At this time, the direction of the unmanned vehicle is periodically meandered to cause the gyro sensor 15 to sway.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling control system for a traveling apparatus such as an unmanned vehicle which maintains a high position detection accuracy.

[0002]

2. Description of the Related Art A conventional unmanned vehicle traveling control system is based on an angle signal and a distance signal from a gyro sensor and an odometer in order to improve position detection accuracy during long-distance traveling. While running. In addition, a correction device (marker or the like) for correcting the position for each constant distance is installed.

[0003]

However, since the gyro sensor originally detects the angular velocity, an error is accumulated in the detected value of the angle obtained by integrating the gyro sensor,
If you use this for a long time, the detected value of the angle will shift,
There is a problem that so-called drift easily occurs and the positional accuracy is not sufficient. Therefore, there is a problem that long-distance movement cannot be performed unless a large number of devices for correcting the information on the current position are provided in the outside world.

The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a traveling control system for an unmanned vehicle, which can improve the positional accuracy during long-distance traveling by means of an internal sensor.

[0005]

According to the present invention, there is provided a drive unit having a traveling unit for traveling on a floor surface and a steering unit for steering the traveling unit in a predetermined direction, and for controlling the attitude of an unmanned vehicle. A gyro sensor for detecting the attitude angle, an odometer for detecting the mileage of the drive device, and a control device for controlling the drive device based on the angle signal and the distance signal from the gyro sensor and the odometer are provided. In such an unmanned vehicle, the gyro sensor is oscillated with a predetermined amplitude and a cycle so that the output characteristics of the gyro sensor are always in a good state.

[0006]

According to the traveling control system of the present invention, the unmanned vehicle is caused to oscillate such that the gyro sensor is swayed at an amplitude and a cycle such that the usage state of the gyro sensor is always a predetermined condition.
It can be used with high sensitivity and accuracy for the speed that you want to detect during running. Therefore, the occurrence of drift can be suppressed and used.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 1 is a schematic diagram of an unmanned vehicle according to the present invention. In FIG. 1, an unmanned vehicle 11 has two drive wheels (not shown) provided on the left and right sides of a vehicle body for traveling on the floor.
While driving the unmanned vehicle by rotationally driving the driving wheels, a driving device 12 that controls the moving direction of the unmanned vehicle by providing a speed difference between the two driving wheels, and a traveling distance that detects the traveling distance of the driving device. Total (not shown) and driven wheel
14 and a gyro sensor 15 that detects the attitude angle of the unmanned vehicle 11
And a control device 16 for controlling the position and attitude of the unmanned vehicle based on the data input from each of these devices. Next, a control block diagram of the unmanned vehicle 11 shown in FIG. 2 will be described. The control device 16 is composed of a microcomputer, a memory, an input / output circuit and the like, and transmits the traveling speed, the command angle and the like to the drive device 12. While the unmanned vehicle 11 is traveling, the distance signal from the odometer 13 is fed back to the control device 16, and the angle signal from the gyro sensor 15 is fed back to the control device 16. The drive device 12 is composed of a motor, a speed reducer, an encoder attached to the motor, a brake, and the like. Gyro sensor
15 uses an optical fiber gyro sensor.

In the traveling control system according to the present embodiment, the angle signal from the gyro sensor 15 and the distance signal from the odometer 13 are introduced into the control device 16 every moment, and the control device 16 uses the signals to drive the unmanned vehicle. 11 position and attitude control.
As shown in the functional block diagram of the traveling control system in this embodiment of FIG. 3, the current position from the reference position and the direction deviation amount calculation 33 are executed based on the angle signal 31 and the distance signal 32, and the current position is set to the reference position. Attitude correction calculation 34 is performed so as to correct. Then, at this time, the direction of the unmanned vehicle 11 is meandered periodically, and the gyro sensor 15 travels while oscillating at a predetermined cycle and amplitude. First, the current position left / right direction deviation amount calculation 33 will be described. The amount of deviation in the left-right direction is calculated for each fixed distance travel, and is calculated by the following formula. Y ₁ = Y ₂ + R × (Σ (θ ₁ −θ ₂ )) / N where Y ₁ : lateral displacement (mm) Y ₂ : lateral displacement before one cycle (mm) R: travel distance (Mm) θ ₁ : current angle (°) θ ₂ : reference angle (°) N: cumulative number of angles.

Next, a posture correction calculation for correcting this deviation amount.
34 will be described. Run a certain distance from the misaligned position,
The steering angle for returning to the reference position is calculated by the following formula. S = G × Y ₁ / R where S: steering angle (°) G: gain (G <1.0). Gain is applied to the right side so that the unmanned vehicle 11 does not pass the reference position and hunt.

Further, a calculation for swaying the unmanned vehicle 11
At 35, a predetermined period (second) and an amplitude (°) are input to the unmanned vehicle 11 as the steering angle in advance as the reference angle θ ₂ . The input data is selected by taking advantage of the characteristics of the optical fiber gyro sensor used.

The characteristics when the gyro sensor 15 composed of an optical fiber gyro sensor is swung will be described. The results of investigating the appearance of drift by fixing the amplitude at ± 1.125 ° and varying the period and the fluctuation time are shown. The cycle is 2, 2.4, 2.5, 2.7, 3.2, 3.5, 4.3
, 6 seconds, and shaking time were 1 minute, 2 minutes, and 3 minutes, and each measurement was performed 5 times. The results are shown in FIGS. FIG. 4 shows drift values in each cycle when the shaking time is set to 1 minute, FIG. 5 is set to 2 minutes, and FIG. 6 is set to 3 minutes. The drift here is the difference from the reference value (0 °) after shaking for a certain period of time. The drift is within 0.5 ° in all cycles at the one-minute fluctuation time shown in Fig. 4, but at the two-minute fluctuation time shown in Fig. 5, the drift is 0.5 during the 2.5-3.5 second cycle. It exceeds ゜. In the shaking time of 3 minutes shown in Fig. 6, when the cycle is 2 seconds, the measured value is 0.1 ° or less up to 3 times and the rest is 0.23 °.
It is 55 °, and it can be seen that the drift is smaller than other cycles. The results of this experiment show that the drift of the optical fiber gyro sensor changes depending on the usage conditions.
Under the conditions set this time, it is highly accurate to use the optical fiber gyro sensor with an amplitude of ± 1.125 ° in a cycle of 2 seconds so that drift does not easily occur.

In this way, by causing the unmanned vehicle 11 to sway while traveling so that the usage state of the gyro sensor 15 becomes a predetermined condition, it is possible to minimize the occurrence of drift.

In the above-mentioned embodiment, the unmanned vehicle 11 is run while being swayed so that the usage state of the gyro sensor 15 directly reaches a predetermined condition. However, the running control device 11 is not limited to this, and the running control device 11 is used. The unmanned vehicle 11 is equipped with a rocking device 17 for rocking the gyro sensor 15, and the rocking device 17 is operated so that the usage state of the gyro sensor 15 becomes a predetermined condition,
The steering may be controlled based on the angle signals of the gyro sensor 15 and the rocking device 17 and the distance signal from the odometer 13. This makes it possible to maintain high positional accuracy during long-distance travel. The unmanned vehicle 11 itself may not be shaken by mounting the shaking device 17 on the unmanned vehicle 11. Further, the drift of the gyro sensor 15 can be kept small even when the unmanned vehicle 11 is stationary. It should be noted that the amplitude and cycle of the sway of the gyro sensor 15 described above are examples of experimental results, and it is obvious that the gyro sensor 15 is not limited to this when set.

[0015]

As described above, according to the present invention, the gyro sensor is swung so that the usage state of the gyro sensor becomes a predetermined condition, and the gyro sensor is run in a state in which drift of the gyro sensor is unlikely to occur. As a result, it is possible to maintain high positional accuracy when the unmanned vehicle is driven.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an unmanned vehicle according to the present invention.

FIG. 2 is a control block diagram showing an embodiment of a traveling control system for an unmanned vehicle according to the present invention.

FIG. 3 is a functional block diagram showing the traveling control system of FIG.

FIG. 4 is a characteristic diagram showing the results of a unit test showing the performance of the optical fiber gyro sensor.

FIG. 5 is a characteristic diagram showing the results of a unit test showing the performance of the optical fiber gyro sensor.

FIG. 6 is a characteristic diagram showing the results of a unit test showing the performance of the optical fiber gyro sensor.

FIG. 7 is a control block diagram of a traveling control system for an unmanned vehicle according to another embodiment of the present invention.

FIG. 8 is a control block diagram of a conventional traveling control system for an unmanned vehicle.

[Explanation of symbols]

11 ... unmanned vehicle, 12 ... driving device, 13 ... odometer, 14 ... driven wheel, 15 ... gyro sensor, 16 ... control device, 17 ... swing device.

Claims (3)

[Claims] 1. A drive device including a traveling unit for traveling on a floor and a steering unit for steering the traveling unit in a predetermined direction, and a gyro sensor for detecting an attitude angle for attitude control of an unmanned vehicle. And an odometer for detecting the mileage of the drive device, and an unmanned vehicle comprising a control device for controlling the drive device based on an angle signal and a distance signal from the gyro sensor and the odometer, A traveling control system for an unmanned vehicle, characterized in that the gyro sensor is caused to travel while being shaken. 2. The traveling control system for an unmanned vehicle according to claim 1, wherein the unmanned vehicle is caused to oscillate at a predetermined amplitude and cycle in order to sway the gyro sensor. 3. An unmanned vehicle is equipped with a rocking device for rocking the gyro sensor at a predetermined amplitude and cycle in order to rock the gyro sensor, and the driving device is also operated based on the angle information of the rocking device while operating the rocking device. The traveling control system for an unmanned vehicle according to claim 1, wherein the vehicle is controlled to travel.