JPH02230407A - Operation control equipment for work vehicle - Google Patents

Abstract

PURPOSE:To improve the detecting accuracy for the tilt of a work vehicle body by setting the steering control sensors at the front and back sides of the vehicle body to detect a horizontal shift amount of the vehicle body to a driving guide and correcting automatically the working value of the work vehicle based on the information on the horizontal shift amount of the vehicle body. CONSTITUTION:A working value correction means 100 decides the front-back tilt of a vehicle body against a reference position based on the shift amounts of the vehicle body to a driving guide which are detected by the steering control sensors 2 at the front and back sides of the vehicle body. At the same time, the means 100 decides the front-back and lateral shifts of the vehicle body to a reference position based on a reading image sensor 13. The sensors 2 are set at the front and back sides of the vehicle body to perform the steering control when the vehicle moves forward and back respectively. The space between both sensors 2 is approximately equal to the length of the vehicle body and much larger than a reference member set at a station. As a result, the front-back tilt of the vehicle body is detected with high accuracy without increasing the size of the reference member.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of application in industry] The present invention provides a steering control sensor that detects the amount of deviation in the width direction of a vehicle body with respect to a travel guide laid along a travel route. installed on the front and rear of the work vehicle as it automatically travels to the work station along a guide.
The work vehicle is provided with a work device, the station is provided with a reference member that displays reference position information of the work device with respect to the station in a plan view, and the work device is provided with a reference member that displays reference position information of the work device with respect to the station. The present invention relates to operation control equipment for a working vehicle, wherein the working vehicle is provided with a reading sensor that reads display information, and the working vehicle is provided with an actuation amount correction means that automatically corrects the actuation amount of the working device based on information from the reading sensor. .

[Conventional technology]

In the operation control equipment for this type of work vehicle mentioned above, steering control sensors are installed on each of the front and rear of the vehicle body so that the work vehicle can automatically travel along the travel guide whether the work vehicle is moving forward or backward. There is.

Even if the stopping position of the work vehicle at the station deviates from the reference position with respect to the work equipment, the reference position information displayed by the reference member installed at the station is read by the sensor installed on the work equipment, so that the work equipment can be adjusted. The operating amount is automatically corrected so that work can be performed appropriately.

By the way, conventionally, as a method of displaying reference position information,
For example, a cross-shaped mark that intersects both the longitudinal direction of the work vehicle and the width direction of the work vehicle is printed on the surface of the reference member, and the mark is read by an image sensor, etc., and the reading position of the mark that has been set and memorized in advance is determined. As a reference, the amount of deviation in the longitudinal direction of the vehicle body, the amount of deviation in the lateral direction of the vehicle body, and the amount of deviation in the tilt in the longitudinal direction of the vehicle body with respect to the reference were calculated (Japanese Patent Laid-Open No. 60-258613). (see official bulletin).

[Problem to be solved by the invention]

According to the conventional configuration, the inclination in the longitudinal direction of the vehicle body is detected as the inclination of the line segment forming the cross-shaped mark read by the sensor. This means that the size of the mark read by the sensor, that is, the length of the line segment, can be made as large as a dog.

To explain, for example, as shown in Figure 3, the slope (
The detection error (80) of the angle θ) is the detection error (
δ) and the interval (j2) between the two points, it is determined by the following formula (see Figure 3).

In other words, the larger the interval (12) between the two points of interest for determining the slope (θ), the smaller the detection error of the slope (θ).

Therefore, in order to increase the distance between the two points read by the sensor, that is, the size of the cross-shaped mark, it is possible to make the size of the reference member installed at the station a dog, but if the size of the reference member is increased, There is a risk that the reference member will get in the way of work, and in fact, it is desirable to make it smaller in order to prevent it from getting in the way of work.

By the way, if you increase the resolution of the sensor's reading position, the 2 points on the cross-shaped mark that you focus on to find the inclination.
Even if the distance between the points is small, the detection error can be reduced, but not only does the sensor become expensive, but the amount of processing of the detected information increases, making it difficult to detect the inclination quickly.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to improve the accuracy of detecting inclination without making the device configuration complicated or expensive or increasing the size of the reference member provided in the station. be.

[Means to solve the problem]

In the operation control equipment for a work vehicle according to the present invention, a steering control sensor that detects the amount of deviation in the width direction of the vehicle body with respect to a travel guide laid along a travel route is configured to move the work vehicle along the travel guide. A reference is provided on each of the front and rear of the body of a work vehicle that automatically travels to the station, the work vehicle is provided with a work device, and the station displays reference position information of the work device with respect to the station in a plan view. A member is provided, the working device is provided with a reading sensor that reads display information of the reference member, and the working vehicle is provided with an automatic correction amount of operation of the working device based on the information of the reading sensor. A working amount correction means is provided, and its characteristic configuration is as follows.

That is, the operation amount correction means determines the inclination of the vehicle body in the longitudinal direction with respect to the reference position based on the amount of deviation from the traveling guide at the front and rear of the vehicle body, respectively, detected by the steering control sensor, and The present invention is configured to determine, based on information from the reading sensor, a deviation in the longitudinal direction of the vehicle body and a deviation in the lateral direction of the vehicle body with respect to the reference position.

[For production]

As mentioned above, the steering control sensors are installed at the front and rear of the vehicle so that the steering can be controlled both when the vehicle is moving forward and when the vehicle is moving backwards, so the distance between them corresponds to approximately the length of the vehicle. Therefore, the distance between the two is much larger than that of the reference member provided at the station.

Therefore, by using information on the amount of deviation in the vehicle width direction at the front and rear of the vehicle with respect to the driving guide detected by steering control sensors installed at the front and rear of the vehicle, it is possible to avoid increasing the size of the reference member provided at the station. In a state where the influence of the detection error of the amount of deviation of the steering control sensor itself is small,
This means that the inclination of the vehicle body in the longitudinal direction can be detected with high precision.

However, the deviations in the longitudinal direction of the working vehicle and in the lateral direction of the working vehicle are determined based on information read from a reference member provided at the station.

〔Effect of the invention〕

As a result, it has become possible to effectively utilize the inherent configuration of the equipment and to detect the inclination in the longitudinal direction of the vehicle body with high precision without increasing the size of the reference member.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIGS. 6 and 7, a traveling guide L" (L) using a light-reflecting tape with a set width is attached to a working vehicle equipped with a load transfer manipulator (1) as a working device. A)
A plurality of load transfer stations (ST) as work stations are installed on the lateral side of the travel guide (L).

In other words, the working vehicle (A) is connected to the traveling guide (L).
The steering is controlled based on the detection information of the steering control sensor (2) that detects deviation in the width direction of the vehicle body, and the vehicle automatically travels along the travel guide (L) to the designated station (ST). The station (ST) is automatically stopped by the load transfer manipulator (1).
It is configured to automatically transfer the load (N) between the vehicle and the work vehicle (A).

However, the steering control sensor (2) is provided at each of the front and rear ends of the vehicle body, and controls the steering based on the detection information of the sensor located on the front side of the vehicle. It is now possible to automatically travel along L).

Note that a one-dimensional image sensor is used as the steering control sensor (2). Then, a reference position is a state in which the work vehicle (A) is properly along the traveling guide (L) so that the deviation in the width direction of the vehicle body with respect to the traveling guide (L) is zero, Traveling guide (L) in the vehicle width direction relative to the reference position
) is used to determine the amount of deviation for steering.

Incidentally, in a state where there is no deviation in the vehicle width direction and no inclination in the vehicle longitudinal direction, the steering control sensor (2) has zero deviation in the vehicle width direction with respect to the traveling guide (L) both in the front and rear. It will be detected that

Also, although not explained in detail, a load (N) transferred to a work vehicle (A) at one station (ST) is unloaded at another station (ST), or is transferred to a work vehicle (A) at one station (ST).
) is transferred to the work vehicle (A) again and transported to the next station (ST).

At the station (ST), when the work vehicle (A) stops at the designated station (ST),
In order to detect the deviation from the reference position in plan view of the manipulator (1) with respect to a preset station (ST), and automatically correct the amount of operation, the station (ST) of the manipulator (1) is ) is provided with a reference member (3) that displays reference position information for the reference position.

As shown in FIGS. 4 and 5, the surface of the reference member (3) is painted black in order to eliminate the influence of ambient light such as illumination, and the reference member (3) is A light source (4) using four red LEDs is embedded from the back side so that the light emitted from it is projected in two directions, so that it is located at a set interval between each of the ing. In the figure, (E) is a dry cell as a power source for the light source (4).

However, the work vehicle (A) is located at the proper stopping position at the station (ST) in the vehicle body longitudinal direction, vehicle body width direction,
And, when the manipulator () is stopped in a state where there is no inclination in plan view and the manipulator (].) is operated with a preset and stored actuation amount, the center of gravity () of the four light sources (4) is
X, Y) are the centers (xo, ya) on the captured image of the image sensor (13), and two light sources (4) are located in the longitudinal direction of the vehicle body and the width direction of the vehicle body, respectively.
The reference position is defined as a state in which the lines connecting the lines coincide with each of the X-axis and the y-axis on the captured image (see FIG. 2).

Note that the X-axis direction is the longitudinal direction of the vehicle body, and the y-axis direction is the longitudinal direction of the vehicle body.
The axial direction is set to be the width direction of the vehicle body.

As shown in FIGS. 6 and 7, the work vehicle (A) is
It is equipped with a pair of left and right propulsion wheels (6) that can be driven and stopped individually by a pair of electric motors (5), and a pair of left and right idle wheels (7) provided at the front and rear ends of the vehicle body, respectively. Based on information detected from the front side of the direction control sensor (2), the pair of electric motors (5) is operated to change the speed of the pair of left and right propulsion wheels (6) so as to differentiate their rotational speeds. It is now possible to steer the vehicle.

Also, a work vehicle (A) for each station (ST)
A stop mark (8) indicating the stop position of the work vehicle (A) is provided on the traveling road side on the side of the traveling guide (I,), and the stop mark (8)
) is provided with a mark sensor (9) that reads information on the mark.

As shown in FIG. 1, various information such as the destination information of the work vehicle (A) and the operation command information of the work device (1) is exchanged between the station (ST) and the work vehicle (A). Optical communication device (10a), (10b) for communication
are provided in each of the work vehicle (A) and the station (ST). In addition, the communication device on the station side (
10b) is connected to a central control device (l1) that manages the operation of the working vehicle (A), and is connected to a communication device (10b) on the working vehicle side.
a) is for controlling the traveling of the working vehicle (A) and the operation of the load transfer manipulator (1);
A> is connected to a work vehicle controller (12) using a microcomputer mounted on the vehicle.

To explain the load transfer manipulator (1),
It is constructed in a so-called multi-joint type, and a two-dimensional image sensor (13) is installed at the tip thereof as a reading sensor for reading information displayed on the load gripper (la) and the reference member (3). is attached. Although not described in detail, the manipulator (1) calculates the operating amount of the electric motor provided at each joint based on detection information of an encoder for detecting the operating amount and various control information stored in advance. The cargo transfer work will be carried out under control based on the above.

However, as will be described in detail later, the work vehicle controller (
12), based on the information read by the image sensor (13), that is, the light receiving position information of the four light sources (4), the amount of correction of the operation amount is determined, and the amount of correction determined is applied to the manipulator (1). controller (14
), so that even if the work vehicle (A) deviates from the proper stopping position with respect to the station (ST), the load gripping tool (1a) can properly grasp the load.

In other words, using the work vehicle controller (12),
An operation amount correction means (100) that automatically corrects an operation amount of the maniplate (1) as a working device based on information read by the image sensor (13) as a sensor for reading display information of the reference member (3). It will be configured.

Incidentally, as the two-dimensional image sensor (13), an ITV using a CCD is generally used. Therefore, the projection light from the reference part shrine (3) is set to red so that the light receiving sensitivity of the two-dimensional image sensor (13) is high.

Next, the configuration of the operation amount correction means (100) will be explained.

As shown in FIG. 2, the imaging information of the image sensor (13) is input to the work vehicle controller (12), is binarized based on its brightness, and is converted into the four lights #(4). ) Coordinates on each captured image (X: +, Y:
+) will be required.

Next, based on the obtained coordinates (X:+,)':+), the centroids (X, Y) of the four light sources (4) are obtained from the following formula.

? Therefore, the value (X) of the X-axis coordinate of the center of gravity (X, Y) is
This corresponds to the amount of deviation in the longitudinal direction of the vehicle body from the reference position (XO, YO), and the value of the y-axis coordinate (Y) corresponds to the amount of deviation in the lateral direction of the vehicle body.

However, the inclination (θ) in the longitudinal direction of the vehicle body is the coordinate value (X1■.Y++)+(X+2+Y+■) of the two light sources (4) lined up in the longitudinal direction of the vehicle body among the four light sources (4). It can be determined based on the following formula, but as is clear from the formula, the coordinate values (X+ +.Y++), (X1
. ,y1. ) The influence of the reading error becomes lower as the denominator value increases.

Xl2

β In the above equation, a is the amount of deviation in the vehicle width direction from the steering control sensor (2) on the front side of the vehicle body with respect to the traveling guide (I,), b is the amount of deviation on the rear side of the vehicle body, l is the distance between the steering control sensors (2) at the front and rear of the vehicle body (see FIG. 3).

Then, based on the value of the center of gravity (X, Y) and the value of the inclination (θ), the amount of movement of each joint that is set and stored in advance is corrected, so that when the work vehicle (A) is stopped, Even if the posture deviates from the reference position with respect to the station (ST), the load gripping tool (1a) of the manipulator (1)
) allows the load to be gripped properly.

Incidentally, the detection accuracy of the inclination (θ) is determined by the amount of deviation (a) detected by the steering control sensor (2). (b
), but since the mounting interval (β) is significantly larger than the interval between the light sources (4) of the reference member (3), the deviation amounts (a) and (b)
) can be made extremely small. Therefore, if the same detection accuracy as in the case of determining the inclination (θ) based on the light receiving position information of the four light sources (4) is sufficient, the deviation amount (a) of the steering control sensor (2) ，(
The detection accuracy of b) may be lower than the reading accuracy of the image sensor (13).

Incidentally, in the case of a general work vehicle (A), the installation interval <p> of the steering control sensor (2) in the longitudinal direction of the vehicle body is around 1 m, and the installation interval of the light source (4) is several meters. It becomes Cm.

[Another example]

In the above embodiment, the reference position information by the reference member (3) is displayed using four red LEDs. A mark or the like may be printed and read by the image sensor (13), and the specific configuration for displaying and reading the reference position information can be modified in various ways.

In addition, in the above embodiment, a light-reflecting tape was used as the traveling guide (L), and the equipment was constructed in a so-called optical guidance type. However, instead of the light-reflecting tape, a magnetic It may be configured in an inductive type, and the specific configuration of the driving guide (L) and the steering control sensor (2
) can be changed in various ways.

In addition, the working device (1) required in "2) to carry out the present invention"
The specific configuration of each part of the work vehicle (A) can be changed in various ways depending on the configuration of the equipment to which the present invention is applied.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the operation control equipment for a working vehicle according to the present invention, and FIG. 1 is a block diagram of the control configuration, FIG. 2 is an explanatory diagram of displacement detection, FIG. 3 is an explanatory diagram of tilt detection, and FIG. 4 5 is a side view of the reference member, FIG. 6 is a schematic plan view of the work vehicle stopped at the station, and FIG. 7 is a front view of the reference member. (A)...Work vehicle, (ST)...Station, (X)...Amount of deviation in the longitudinal direction of the vehicle body, (Y)...Vehicle body Amount of deviation in the width direction, (θ)
・・・・・・Inclination in the longitudinal direction of the vehicle body, (1)・・・・・・
・Working device, (4)...Sensor for steering control,
(3)...Reference member, (13)...Reading sensor (100)...Operation amount correction means.

Claims (1)

[Claims] A steering control sensor (2) that detects the amount of deviation in the width direction of the vehicle body with respect to the travel guide (L) installed along the travel route is installed at a work station (2) along the travel guide (L). The work vehicle (A) is provided with a work device (1), and the work vehicle (A) is provided with a work device (1), and the work device (1) is provided at the front and rear of the vehicle body of a work vehicle (A) that automatically travels at the station (ST).
A reference member (3) is provided for displaying reference position information of the work device (1) with respect to the station (ST) in plan view, and the work device (1) is provided with a reference member (3) that displays reference position information of the work device (1) with respect to the station (ST).
) is provided with a reading sensor (13) for reading displayed information, and the working vehicle (A) is provided with an operation for automatically correcting the operating amount of the working device (1) based on the information of the reading sensor (13). The operation control equipment for a working vehicle is provided with an amount correction means (100), wherein the operation amount correction means (100) adjusts the amount of movement detected by the steering control sensor (2) at the front and rear of the vehicle body. Based on the amount of deviation with respect to the guide (L), the inclination (θ) of the vehicle body in the longitudinal direction with respect to the reference position is determined, and based on the information of the reading sensor (13), the vehicle body longitudinal direction with respect to the reference position is determined. Operation control equipment for a work vehicle configured to discriminate between a deviation in the direction (X) and a deviation in the width direction of the vehicle body (Y).