JPH0493683A - Range finer for movable body - Google Patents

Abstract

PURPOSE:To make it trackable accurately at high sped by predicting a tilt angle in a receiving part on the basis of the tilt angle and measuring distance of the receiving part to the travel speed and direction, and changing a sense of the receiving part. CONSTITUTION:A predicting means 8E calculates a position of a carrier 1 and a deviation in the traveling direction after setting time for the position and traveling position of this carrier 1 at the current point of time on the basis of the detected result of a speed detecting means 8D each time tracking command signal is outputted out of a timer 8B. A tilt angle calculating means 8F calculates a tilt angle at for making a range finder 7 face to a reflector 6 after the setting time, on the basis of the detected result of a tilt angle detecting means 8C at the current point of time and the measured result of the range finder 7 plus the calculated result of the predicting means 8E. With this constitution, tracking is can be done accurately at high speed and, what is more, a distance ranging from the specified movable body and an object position is measurable in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention detects the position of a work vehicle, which is necessary when automatically driving a work vehicle such as a transport vehicle for transporting materials at a construction site. This is a device used when performing measurement based on the distance from a point to two reference positions. Specifically, it is a device that uses spatial propagation waves (
A distance meter that receives electromagnetic waves or sound waves and measures the distance to the index tool is installed on a moving object such as a work vehicle, and the distance meter is oriented toward the index tool so as to receive the spatially propagated waves from the index tool. The present invention relates to a distance measuring device for a moving object, which is provided with a tracking means for correcting the direction of a receiving section of the meter.

[Conventional technology]

In this type of distance measuring device for a moving object, the positional relationship between the indicator and the distance meter changes as the moving object moves. Due to such a change in positional relationship, if the direction of the receiving part of the rangefinder deviates from the direction facing the indicator, it will not be possible to measure the distance as expected. Tracking is required to correct the orientation of the receiver so that it faces the tool.

Conventionally, as a tracking means for performing such tracking, a television camera is installed in a state where the direction can be changed integrally with the receiving section and facing the same direction as the receiving section, and an indexing device is used in the photographed screen of the television camera. The relationship between the orientation of the receiver and the indicator is determined from the image position of the image, and the orientation of the receiver is changed so that the image of the indicator is placed at a predetermined position such as the center of the video screen, and the orientation is corrected to face the indicator. The means to do so are known.

[Problem to be solved by the invention]

However, the conventional technique has disadvantages in that it takes time to process images, and the moving speed of the moving object is limited.

An object of the present invention is to perform accurate and high-speed tracking.

[Means to solve the problem]

The characteristic configuration of the distance measuring device for a moving object according to the present invention is such that the tracking means includes a driving device for changing the direction of the receiving section, a command means for intermittently outputting a tracking command signal, and a moving object for moving the moving object. an inclination angle detection means for detecting an inclination angle of the orientation of the receiving section with respect to a direction; a speed detection means for detecting the moving speed of the moving body; and a detection means for the speed detection means each time a tracking command signal is output from the command means. Based on the results, a prediction means is provided to calculate the deviation of the position and movement direction after a set time from the current position and movement direction of the moving object, and the detection result of the tilt angle detection means and the distance meter measurement are provided. Based on the result and the calculation result of the prediction means, a tilt angle calculation means is provided which calculates a tilt angle for directing the receiver toward the indicator after a set time, and after the set time, the tilt angle or the calculation result of the tilt angle calculation means is calculated. The point is that direction control means is provided for operating the drive device so that the driving device is operated.

[For production]

Predicts the inclination angle to direct the receiver toward the indicator after a set time based on the moving speed of the moving object, the inclination angle of the receiving section relative to the moving direction of the moving object, and the distance measured by the rangefinder. Then, after a set time, the direction of the receiver is changed so that the predicted inclination angle is achieved, and the receiver is directed toward the index tool.

Although differences inevitably occur between the actual position and moving direction of the moving body after the set time and the position and moving direction calculated by the prediction means due to wheel slipping, etc.
By selecting the setting time appropriately based on the difference,
Since the inclination angle at which the receiver should be directed toward the indicator after the set time can be predicted with extremely high accuracy, the receiver can be reliably directed toward the indicator.

〔Effect of the invention〕

As a result, according to the present invention, there is no need for time-consuming image processing for tracking that always directs the receiving unit toward the index tool regardless of the movement of the moving object, and the tracking can be performed without limiting the moving speed of the moving object. It has become possible to measure the distance from the desired moving object to the target position by accurately and quickly.

〔Example〕

Examples of the present invention are shown below.

A self-propelled transport vehicle (1), which is an example of a mobile object, is shown in Figure 1.
As shown in Fig. 3, position detection means (2) detects the position (P) of the transport vehicle (1) on the
), a direction detecting means (3) for detecting the moving direction of the transport vehicle (1), the position detecting means (2) and the direction detecting means (
automatic travel control means (3) that operates the travel means (4) so as to arrive at the target position (Po) based on the detection result of
5).

The position detection means (2), as shown in FIG.
The origin of the coordinates is the first target position (Pl) of the position detection reference, and the position separated from the origin by a set distance (10) in the X-axis direction is the second target position (P2) of the position detection reference. from the position (P) of the transport vehicle (1) to the first
The first step is to measure the distance (11) to the target position (Pl) of
a distance measuring device (A1), and a second distance measuring device (A1) that measures the distance from the position (P) of the transport vehicle (1) to the second target position (P2).
distance measuring device (A2), these distance measuring devices (Al), (A
2) Calculating means (B) for calculating the coordinate values (X, Y) of the position (P) of the transport vehicle (1) from the respective measured distances (z +), (12) and the set distance (β.); Consists of.

The first and second distance measuring devices (AI), (A2) are
As shown in Fig. 4, the target positions (P, ) and (P
A distance meter that receives the spatially propagating waves from the index devices (6) provided in 2) and measures the distance (!) between the index devices (6) as the distance (lt), (12) of the object to be measured. (7), and the distance meter (7) facing the index tool (6) so as to receive the spatially propagating waves from the target index tool (6).
and a tracking means (8) for correcting the direction of the whole.

The index tool (6) is a reflecting mirror that uses a corner cube to reflect the incident light beam in a direction parallel to the direction of incidence of the light beam.

The distance meter (7) is equipped with an infrared light projector and a receiver, and measures the distance to the reflector (6) from the time it takes to project the infrared light, reflect it on the reflector (6), and receive the light. It is a distance meter. As shown in FIG.
are individually supported rotatably around the same vertical axis (y), and each of these turntables (9) has a support frame (1
0) so as to be swingable around the horizontal axis (X), and a distance meter (7) corresponding to each of the support frames (10) is attached. In other words, the range finder (7) changes the rotation direction of the turntable (9) and the rocking direction of the support frame (10).

The tracking means (8) moves the rangefinder (7) to the reflector regardless of the relative displacement in the horizontal direction between the rangefinder (7) and the reflector (6) as the transport vehicle (1) moves. (6) This is a means for making distance measurement possible. As shown in FIG. 4, a stepping motor (8A) rotates the turntable (9) to change the direction of the distance meter (7).
) (an example of a drive device), a timer (8B) that intermittently outputs a tracking command signal, and an inclination that detects the inclination angle (α) of the orientation of the distance meter (7) with respect to the moving direction of the transport vehicle (1). An angle detection means (8C), a speed detection means (8111),
It consists of a prediction means (8E), a tilt angle calculation means (8F), and a direction control means (8G).

The speed detecting means (8D) is a means for detecting the moving speed of the transport vehicle (1), and is a means for detecting the moving speed of the transport vehicle (1).
A rotation sensor (8) detects the rotation speed of
a), (8b), and these rotation sensors (8a), (
Speed calculation means (8C) that calculates the speed from the detected rotation speed of 8b) and calculates the moving direction from the difference in the detected rotation speed.
).

Each time the timer (8B) outputs a tracking command signal, the prediction means (8E) predicts the current position and moving direction of the transport vehicle (1) based on the detection result of the speed detection means (8D). Transport vehicle after set time (1
) is a means for calculating deviations in position and movement direction. In other words, 1. Calculate the position and moving direction of the transport vehicle (1) after a set time on the XY coordinates, with the current position and moving direction of the transport vehicle (1) being the origin and Y-axis direction, respectively. It is a means.

The tilt angle calculation (8F) is performed based on the current detection result of the tilt angle detection means (8C), the measurement result of the distance meter (7), and the calculation result of the prediction means (8E) after a set time. 7) to face the reflecting mirror (6).

As shown in FIG.
) to the reflecting mirror (6) (I angle and inclination angle (α)
, etc., are actually measured by a distance meter (7) and an inclination angle detection means (8C) and are accurate.

On the other hand, the movement amount (D) is a predicted value calculated by the prediction means (8E).

Now, let it be the distance from the transport vehicle (1) to the reflector (6) after the set time, and set the distance meter (7) to the reflector (6) at the set time.
If the inclination angle to direct the direction is αt, then lt=± r= 5in-' (D/it)・sin a'rα
t=α+γ, resulting in αt−α+5ln−·CO3α.

Therefore, by performing the above calculation, it is possible to determine the angle of inclination (αt) for directing the range finder (7) toward the reflecting mirror (6) at the set time. And the wheel (la),
(lb) slip, etc., the actual position and moving direction of the transport vehicle (1) after the set time and the prediction means (8E)
It is inevitable that a difference (error) will occur between the position and direction of movement calculated in By appropriately selecting the setting time, that is, the output interval of the tracking command signal, based on the magnitude of the error in The reliability of αt can be ensured by allowing the direction of movement to be handled as the actual position and direction of movement.

As shown in FIG. 1, the calculation means (B) calculates COSλ
”(I!o”+7+2122)/2・io・IX=
This is a means for calculating the coordinate values (X, Y) of the position (P) of the transport vehicle (1) using the following three equations: 11-CO3λ Y=4', ・sio+λ.

As shown in FIG. 1, the direction detection means (3) detects the measured distances (z +) and (z 2) of the first and second distance measuring devices (AI) and (A2), and the set distance. (I!0) and
A means for applying blade pressure to the moving direction of the carrier (1) as an inclination angle (θ) with respect to the Y-axis direction based on the inclination angle (α) detected by the inclination angle detection means (8C), COSλ=
(1'o"+1+2f2')/2 ・(io・11 to λ= cos-'((lo2+f+2-12")/2
・io・f! 1), and θ is determined from this formula and λ=(π/2)−(α−θ).

(11) and (12) are the support frame (10) and the horizontal axis (X
) A stepping motor rotates the distance meter (7) to change the direction up or down, and an encoder detects the direction.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a plan view, FIG. 2 is a schematic configuration diagram of a distance measuring device, FIGS. 3 and 4 are block diagrams, and FIG. 5 shows an operation showing a tracking operation. FIG. (6)...Indicator, (7)...Distance meter, (1)...Moving object, (8)...Tracking means, (8A )... Drive device, (8B)...
...Command means, (8C) ...Inclination angle detection means, (8E) ...Prediction means, (8F) ...
・Inclination angle calculation, (8G)...Direction control means.

Claims (1)

[Claims] A rangefinder (which receives spatially propagating waves from an index tool (6) installed at a target position and measures the distance to the index tool (6))
7) is provided on the moving body (1), and tracking corrects the direction of the receiving section of the range finder (7) to face the index tool (6) so as to receive the spatial propagation wave from the index tool (6). Means (8)
A distance measuring device for a moving body, comprising: a driving device (8A) for changing the direction of the receiving section; and a commanding means for intermittently outputting a tracking command signal. (8B), and a tilt angle detection means (8C
), a speed detection means (8D) for detecting the moving speed of the moving body (1), and each time a tracking command signal is output from the command means (8B), based on the detection result of the speed detection means (8D). A prediction means (8E) is provided for calculating the deviation of the position and movement direction after a set time from the current position and movement direction of the moving body (1), and the current tilt angle detection means (8C) detects the deviation of the position and movement direction after a set time. Based on the result, the measurement result of the distance meter (7), and the calculation result of the prediction means (8E), the inclination angle (αt
), and a direction control means (8G) that operates the drive device (8A) so that the tilt angle (α) becomes the calculation result of the tilt angle calculation means (8F) after a set time. ) is a distance measuring device for a moving object.