JPH01250110A - Position detector for work vehicle guiding device using beam light - Google Patents

Abstract

PURPOSE:To detect the position of a work vehicle body without using any exclusive sensor, etc., by measuring the time covering the time point when a photodetecting means receives the guiding beam light through its next receiving time point and discriminating the position of the vehicle body. CONSTITUTION:A beam light projecting device 1 is set at the ceiling side of a path so that the device 1 can perform the repetitive reciprocating scans of the guiding beam light A along the lengthwise direction of the path. A work vehicle body V contains a pair of front and back photodetectors S1 and S2 for its drive control. Then a timer contained in a controller counts two continuous times T1 and T2 covering the time point when the front photodetector S1 receives the light A through its next receiving time point. Thus the position of the body V is discriminated in the lengthwise direction of the work process based on the ratio between both times T1 and T2. As a result, the position of the body V can be detected on a set locus without using any exclusive detecting means like a sensor for measurement of distance, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a beam light projection means for projecting a guiding beam light onto the ground side at a set scanning angle and a set scanning speed in the traveling direction of the vehicle body. a light receiving means provided on the vehicle body so as to repeatedly scan the guiding beam light back and forth along the vehicle body; The present invention relates to a position detection device in a work vehicle guidance system using beam light, which is provided with a steering control means for controlling the steering so that the vehicle body travels along a set travel trajectory based on position information.

[Conventional technology]

For example, if the vehicle is to automatically travel along a set travel trajectory during each of multiple work strokes, when the vehicle reaches the end of one work stroke, it will automatically move to the next work stroke. However, in order to detect whether or not the vehicle body has reached the end of the working stroke, it is necessary to provide means for detecting the position of the vehicle body on the set traveling trajectory in each working stroke.

Therefore, in the past, for example, a reflector for detecting the position of the vehicle body was installed at a position corresponding to the end of the work process, and an ultrasonic sensor or the like was installed on the vehicle body to measure the distance to the reflector. The position of the vehicle body on the travel trajectory was detected.

[Problem to be solved by the invention]

In the above conventional configuration, it is necessary to install a distance measuring sensor on the vehicle body side and also install a distance measuring reflector at the end of the work process, which not only makes the device configuration complicated and expensive, but also makes it necessary to install a distance measuring reflector at the end of the work process. The work of installing the reflector was troublesome.

By the way, in a cleaning vehicle that cleans the passageways inside a building, the wall located at the end of the working stroke can be used as a reflector for distance measurement; The sensor cannot be omitted, and improvements have been desired.

The present invention has been made in view of the above circumstances, and includes:
The purpose is to be able to detect the position of the vehicle body on the set travel trajectory without providing a dedicated sensor for position detection.

[Means to solve the problem]

In the position detection device in the work vehicle guidance system using beam light according to the present invention, the beam light projection means for projecting the guidance beam light onto the ground side is configured to move the vehicle body along the traveling direction at a set scanning angle and at a set scanning speed. A light receiving means is provided on the vehicle body so as to repeatedly scan the guiding beam light back and forth, and the light receiving position of the guiding beam light changes as the position changes in the width direction of the vehicle body, and the light receiving position of the light receiving means a steering control means for controlling the steering so that the vehicle body travels along a set traveling trajectory based on the information, and a first characteristic configuration thereof is that the light receiving means A time measuring means for measuring the time from the time when the exclusive beam light is received until the next time the light is received, and the position of the vehicle body in the length direction of the set traveling trajectory is determined based on the information of the time measuring means. The point is that a position determining means is provided to determine the position.

By the way, when multiple work strokes are set side by side in the width direction of the vehicle body, each time the vehicle body moves to the next work stroke,
The distance between the vehicle body and the beam light projection means will change,
Even if the vehicle body position on the set travel trajectory in each work process is the same, the light receiving means receives the guiding beam light from the time it receives it next depending on the distance between the vehicle body and the beam light projection means. The time will vary.

Therefore, in the second characteristic configuration, the position of the vehicle body on the set traveling trajectory can be accurately detected in each of the plurality of work processes lined up in the width direction of the vehicle body, regardless of the difference in the distance between the vehicle body and the beam light projection means. In order to do this, the position determining means is configured to determine the position of the vehicle body based on the ratio of two times consecutively measured by the time measuring means.

[For production]

Since the guiding beam light is repeatedly scanned back and forth along the running direction of the vehicle body at a set scanning angle and a set scanning speed, it is possible to determine the position of the vehicle body on the set traveling trajectory along the scanning direction relative to the beam light projection means. Accordingly, the time from when the light receiving means that receives the guiding beam light receives the guiding beam light until the next time it receives the guiding beam light changes to become shorter as the vehicle body approaches the end of the working process. (1st
(see figure).

Therefore, in the first characteristic configuration, the time from when the light receiving means receives the guidance beam light until the next time it receives the light is measured, and the vehicle body position on the set travel trajectory is determined based on the measured time. Let it happen.

However, since the guidance beam is scanned back and forth,
From the time when the light receiving means receives the guiding beam light to the next time when the guiding beam light is received, the guiding beam light is generated twice during one reciprocating scan, and the time between the two times is The ratio is regardless of the distance between the vehicle body and the beam light projection means.
The value corresponds to the position on the set travel trajectory.

Therefore, in the second characteristic configuration, the position of the vehicle body is determined based on the ratio of two times consecutively measured by the time measuring means.

〔Effect of the invention〕

Therefore, by effectively utilizing the configuration originally provided in the device, it has become possible to detect the position of the vehicle body on the set trajectory without providing a means dedicated to position detection such as a distance measuring sensor.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a guidance device for a cleaning work vehicle that cleans while automatically traveling along a passage in a building will be described below with reference to the drawings.

As shown in FIGS. 1 to 3, a plurality of working strokes along the longitudinal direction of the passage are arranged parallel to each other and lined up in the width direction of the passage.

Then, a beam light projection device (1) as a beam light projection means directs a guiding beam light (A) at a set scanning angle (±α ) is provided so as to project the image toward the upper surface of the vehicle body (V) running on the floor along the longitudinal direction of the passage while repeatedly scanning back and forth at a set scanning speed.

In other words, the scanning trajectory of the guiding beam (A) on the floor surface corresponds to the set traveling trajectory in each work process.

As shown in FIGS. 1 and 8, on the upper surface of both the front and rear ends of the vehicle body (V), there are provided a pair of front and rear pairs for detecting the light receiving position in the vehicle body width direction with respect to the scanning direction of the guiding beam light (A). light receiver (s-+') for steering.

(St) is provided, and between the pair of front and rear steering light receivers (Sr) and (Sl) is a reflector that reflects the incident light in the direction of incidence. A reflector (C) is provided with its light reflecting surface facing upward.

In other words, the pair of front and rear steering light receivers (S, )
.

(S2) corresponds to the light receiving means whose light receiving position of the guiding beam light (A) changes as the position changes in the vehicle width direction.

Then, as the vehicle body (V) reaches the end of each work stroke, it repeatedly moves backwards and forwards for each -stroke, while moving closer to the next work stroke, and each In the work process, the pair of front and rear light receivers (Sl), (
Steering is controlled to automatically travel along the guidance beam (A) based on the light receiving position information of the SZ), and the cleaning work is automatically performed while reciprocating in the set range of the passage. become.

Although details will be described later, the pair of front and rear light receivers (Sl
) and (S2), the vehicle body position on the set travel trajectory in each work process is detected using the light reception information of the one located on the forward side of travel, and the set position corresponds to the end of the work process. As the vehicle body (V) reaches the end of its working stroke, it is determined that the vehicle body (V) has reached the end of its working stroke.

To explain the beam light projection device (1), the fourth
As shown in the figure and FIG. 5, the laser beam projected from the semiconductor laser (2) is moved by a scanning electric motor (Ml) equipped with an encoder (e,) to an axis ( A reflecting mirror (3) that is reciprocated and oscillated at a set scanning speed over the set scanning angle (±α), and the reflecting mirror (3) and the electric motor for scanning (M, ) of the support member (4) along the longitudinal direction of the passage (P2
) a rocking electric motor (M2) equipped with an encoder (et) for rocking operation around the vehicle body (V); A light receiver (S3) is provided to receive the reflected light of the guiding beam light (A) reflected by the reflector (C).

That is, the light receiver (S,) receives the guiding beam light (S,).
The vehicle body (V
), the state is such that the guiding beam light (A) reflected from the reflector (C) of the vehicle body (V) is received at the same period as the scanning period of the guiding beam light (A). but,
When the vehicle body (V) reaches the end of the working stroke and moves to the next working stroke, the vehicle body (V) is moved to the non-light receiving state based on the light receiving information of the light receiver (S3). This makes it possible to detect when the machine has moved on to the next work process.

As shown in FIG. 6, based on the light reception information of the light receiver (S,) that receives the reflected light of the guiding beam light (A) by the reflector (C), the swinging electric motor (M) is operated. A microcomputer-based control device that automatically operates the
5) is provided.

Next, the operation of the control device (5) of the beam light projection device (1) will be explained based on the flowchart shown in FIG.

However, the information on the scanning angle range by the scanning motor (Ml) and the oscillating angle by the oscillating motor (Ml), that is, the information on the projection position corresponding to each work process of the guiding beam light (A), are as follows: The length of the work stroke in the passageway that is the work range and the position of each work stroke in the width direction of the passageway,
In addition, settings are stored in advance based on the number of work steps and the like.

First, the operation of each part is started with the vehicle body (V) positioned at the corner of the passage corresponding to the starting end of the first working stroke.

Next, the scanning motor (M,) is attached to the husband, and based on the information of the encoder (el), the set scanning angle (±
α) While repeatedly scanning back and forth at a set scanning speed, the guiding beam (A) is projected to a position corresponding to the first working stroke, which is near one wall in the width direction of the passage. The swinging electric motor (?h) is operated based on the detection information of the attached encoder (e2).

The scanning electric motor ( Based on the detection information of the encoder (el) attached to As the light receiver (S,) is in a non-light receiving state for a long period of time, the rocking electric motor (n2) is driven based on the detection information of the encoder (et) attached thereto, The reflecting mirror (3) is aligned with the axis (P2) along the longitudinal direction of the vehicle body so that the projection position of the guiding beam light (A) in the vehicle width direction, that is, the passage width direction is a position corresponding to the next work process. ) to change the projection position of the guiding beam (A) (see FIG. 2).

However, the guiding beam light (
The projection position of A), that is, the value of the swing angle detected by the encoder (e2) attached to the swing motor (Mt) is
If the value corresponds to the final work step, it is determined that the work is complete and all processing is ended.

To explain the structure of the vehicle body (V), as shown in FIGS. 8 and 9, driving motors (M3) are installed at each of the front, rear, left and right sides of the lower part of the vehicle body (V). A running wheel (6) that can be driven and stopped is provided. however,
The running wheels (6) are configured so that they can be steered separately, front and rear, as a pair of left and right wheels by a steering motor (M4).

In other words, a two-wheel steering type that only steers a pair of left and right running wheels (6) on the front side with respect to the vehicle running direction;
There are three types: a parallel steering type in which a pair of left and right running wheels (6) are steered in the same phase and at the same angle in both the front and rear, and a four-wheel steering type in which the front and rear are steered in the same phase and at the same angle.
Different steering types are available for selection. As will be described later, when controlling the steering so that the vehicle automatically travels along the guidance beam (A) in each work process, a two-wheel steering system is used, and
When moving to the next work process, the parallel steering method described above is used to move the machine closer to its width. The four-wheel steering type is used, for example, when turning the vehicle after completing work in one passage and moving to the next passage.

In Fig. 8, (7) is a rotating brush for cleaning, (8) is a water absorption device installed at the front and rear of the vehicle body, and (9) is a distance measuring device.
This is a step sensor using an ultrasonic sensor for use in the vehicle, and measures the height from the floor to prevent the vehicle body (V) from falling down stairs or the like. Further, (lO) is a non-contact type ultrasonic sensor for detecting obstacles, which is connected to the vehicle body (
Thin membranes are provided on each of the front, rear, left and right sides of the vehicle body (v), so that the vehicle body (v) can be brought to an emergency stop when the presence of even one of them is detected. Also, (1
Reference numeral 1) is a contact-length obstacle detection sensor that also serves as a bumper, and is provided so as to surround the vehicle body (V).

Next, a control configuration for automatically driving the vehicle body (V) along the guidance beam (A) will be described.

As shown in FIG. 9, the pair of front and rear light receivers (Sl)
, (Based on the light receiving position information of each S, calculate the positional deviation (χ) in the vehicle width direction with respect to the set travel trajectory in each work process and the inclination (ψ) in the scanning direction, that is, with respect to the set travel trajectory. At the same time, based on the detected information, the steering motor (M4) on the front side of the vehicle is operated, and each of the traveling wheels (6) is operated so that the vehicle body (V) travels at a set speed. A control device (12) using a microcomputer is provided to operate an attached traveling motor (M3).

That is, using the control word W (12), the vehicle body (V) is guided to the set travel trajectory based on the light receiving position information of the pair of front and rear light receivers (Sl) and (SZ) as light receiving means. a steering control means (100) that performs steering control so that the light receiver (S) travels along the same direction;

A time measuring means (101) for detecting the time (T or T2) from when the (SZ) receives the guiding beam light (A) until the next time the guiding beam light (A) is received;
Based on the information 101), each position determining means (102) is configured to determine the position of the vehicle body (v) in the longitudinal direction of the set travel trajectory.

In FIG. 9, (e,) is an encoder attached to each of the traveling motors (M3), and the traveling speed can be adjusted based on the detected information. Also, (R
f) is a steering angle detection potentiometer on the front side of the vehicle body; (
Rr) is a steering angle detection potentiometer on the rear side of the vehicle body.

Position deviation (χ) in the width direction of the vehicle body for the above working process
To explain the configuration for detecting the angle and the inclination (ψ) with respect to the length direction, as shown in FIG. A light receiving element (D) which receives the guiding beam light (A), the elements being arranged side by side in the width direction of the vehicle body.
Light receiving position (L).

(X2), with the position of the light receiving element (0°) located at the center in the width direction of the vehicle as a reference, the right side is determined to be a large positive value, and the left side is determined to be a large negative value. It is.

Based on the received light values W (XI), (X,) of the pair of front and rear light receivers (Sl) and (SZ), and the mounting distance in the longitudinal direction of the vehicle body, the following (i) The above-mentioned slope (ψ) is determined from the equation.

ψ=jan−' ((XI XZ)/l−)−”
・(1) Furthermore, the positional deviation (χ) in the width direction of the vehicle body is
The light receiving position of the pair of front and rear light receivers (Sυ, (the light receiving position of the front side of the S) may be used as is,
The average value of both the front and rear light receiving positions (XI) and (XZ) may be used.

Further, based on the position deviation (χ), the inclination (ψ), and the current steering angle (0) by the steering motor (M4), the target steering is calculated using the following formula (ii). Steering control is performed by setting the direction angle (θf).

θf=4.・2 for χ1・3 for ψ1. θ・・・・・・(
ii) However, K, , , , and 2 are constants set in advance according to the control characteristics.

In other words, the target steering angle (θf
), and the pair of left and right running wheels on the front side of the vehicle (1)
The process of steering the steering wheel corresponds to the steering control means (100).

To explain the running of the vehicle body (V), the 11th
As shown in the flowchart in the figure, the vehicle body (V)
The vehicle starts traveling in a state where it is located at the preset position in the first working stroke, and after the vehicle starts traveling, the front side of the front and rear pair of light receivers <Sl) and (SZ) The control device (1
A timer configured using the internal function of 2) is used to measure the two consecutive times (TI) and (TZ).
The position of the vehicle body (ν) in the length direction of the working process is determined based on the ratio of
The position deviation (χ
) and the inclination (ψ) approach zero, the steering is controlled while automatically setting the target steering angle (θf) according to equation (ii) above, and the guiding beam light (A
) will be guided to go straight along the scanning trajectory.

To explain the detection of the position 1t(x) of the vehicle body (v), the beam light projection device (1) directs the guiding beam light (A) to a position corresponding to the set travel locus in each work process. Even if the scanning angle (±α) of the guiding beam light (A) is constant, the guiding beam light (A) is projected in the direction of the width of the vehicle. The scanning angle range on the running surface of the vehicle body (V) changes depending on the swing angle in the direction.

However, as shown in FIG.
) is reciprocally scanned at a constant scanning angle (±α), so the light receiver (s, ), (S2) receives the guiding beam light (A) twice during the reciprocating scan. I will do it. Then, the time (TI) of the two light reception intervals before and after that,
The ratio of (TZ) is determined by the difference in the swing angle of the beam light projection device (1), that is, in any of the plurality of work strokes lined up in the width direction of the vehicle body, even if the vehicle body position in the length direction of the work strokes is the same. The values will be the same.

Therefore, based on the height (h) from the light receivers (Sl) and (SZ) of the vehicle body (V) to the beam light projection device (1) and the scanning angle of 1 degree (±α), The distance (x) from the reference position directly below the beam light projection device (1) is
As shown in (ij) 2 below, it can be determined from the ratio of the time (TI) and (TZ) of the two light reception intervals.

That is, the light receiver (Sl) uses the timer.

Two consecutive times (TI) from the time when (St) receives the guidance beam light (A) until the next time it receives the guidance beam light (A)
, (TZ) corresponds to the time measuring means (101), and the process of determining the position (x) of the vehicle body (ν) from the above equation (iii) corresponds to the position determining means (102). It will correspond to

Then, based on the value of the position (x) obtained by this formula (ij), it is determined whether the vehicle body (V) has reached the end of the working stroke, and the system determines whether the vehicle body (V) has reached the end of the working stroke. Accompanied by,
This will cause it to stop running.

After the vehicle stops running, it is determined whether or not it is the final stroke based on the number of work strokes set and stored in advance, and if it is the final stroke, the entire process is ended.

On the other hand, if it is not the final stroke, the two-wheel steering type is switched to the parallel steering type, and the guiding beam light (A
) is moved in parallel toward the next working process until it receives light again.

Then, as the pair of front and rear light receivers (Sl) and (SZ) become in a state where they receive the guidance beam light (A) again, the system switches to the two-wheel steering mode,
After moving the vehicle body (v) to the starting end of the work stroke based on the light reception information of the pair of front and rear light receivers (St) and (Sl), the vehicle body (v) is switched back and forth again to start traveling in the next work stroke. I will let you do it.

(Another Example) In the above example, the case where the guidance beam light (A) is projected from the ceiling side is exemplified.
), and receives the guiding beam light (A) from the lateral side, (52)
may be provided on the lateral side of the vehicle body (V).

To explain, as shown in FIG. 12, the guiding beam (A) is directed to a virtual plane (F) that is parallel to the running surface on which the vehicle body (V) runs and passes through the beam projection position. The guidance beam light (
A) is configured so that a positional deviation in the width direction of the vehicle body with respect to the work process can be detected as a positional deviation in the vertical direction on the side surface of the vehicle body, and the light receiver (Sl ) and (Sl) are provided so that their light receiving surfaces become longer in the vertical direction of the vehicle body so that the light receiving position in the vertical direction of the vehicle body can be detected.

In other words, when the position of the vehicle body (ν) in the width direction shifts away from the beam light projection device (1), the light receiving positions of the vehicle body-side light receivers (Sl) and (S2) move upward from the proper position. When the vehicle body (V) is deflected and the position in the width direction of the vehicle body (V) shifts toward the side approaching the beam light projection device W(1), the light receiving positions of the light receivers (S1) and (si) on the vehicle body side are as follows. Each time it deviates downward from the proper position.

Then, in each of a plurality of work strokes lined up in the width direction of the passage, the light receiver (S
l) and (SZ) so that the light receiving positions are at the same position.
The vertical projection direction of the guidance beam light (A) is moved around an axis along the vehicle running direction so that the value of the set angle (β) becomes a value corresponding to the position of each work stroke. It is to make it.

In this case, even outdoors where there is no ceiling on which the beam light projection means is installed, the vehicle body (ν) can be guided through each of the plurality of work steps without moving the beam light projection means, as in the above embodiment. be able to.

Incidentally, even when the beam light projection device (1) projects the guiding beam light (A) from the sideways position of the vehicle body, one of the light receivers (S, ) and (St) on the vehicle body side is connected to the guiding beam light (A). The position (x) of the vehicle body (V) is determined in the same manner as in the above embodiment based on the ratio of the two consecutive times (TI) and (T2) before and after the light reception interval for receiving the beam light (A) for the vehicle. can be determined.

However, when the beam light projection device (1) projects the guiding beam light (A) from the lateral side of the vehicle body, the width direction of the vehicle body corresponding to the height (h) relative to the beam light projection device (1) in the above embodiment is The distance from the beam light projection device (1) at , will change depending on the position of the working stroke in which the vehicle body (v) travels. Therefore, the value of height (h) in the above formula (iii) is corrected to a value corresponding to the distance from the beam light projection device (1) in each work process based on the number of work processes traveled, etc. Become.

Further, in the above embodiment, the case where steering is performed using a two-wheel steering method is exemplified, but for example, the positional deviation (χ) in the width direction is corrected using a parallel steering method, and the inclination (
ψ) may be corrected using a four-wheel steering system. In addition, the positional deviation in the width direction (
The steering may be performed by detecting only the guidance beam light (χ), and the specific configuration of the steering control means (100), etc.
The specific configuration of each part for guiding the vehicle body (V) using A) can be changed in various ways.

Further, the present invention can be applied to devices for guiding various work vehicles, including the specific configuration of the beam light projection means (1) and the vehicle body (V), as well as various types of devices equipped for automatic driving. The specific configuration of sensors and the like can be changed in various ways.

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 position detection device in the work vehicle guidance device using beam light according to the present invention, in which FIG. 1 is a side view of the entire working area, FIG. 2 is a front view thereof, and FIG. 3 is a plan view thereof. , FIG. 4 is a cutaway side view of the beam light projection means, FIG. 5 is a front view thereof, FIG. 6 is a block diagram of the control configuration of the beam light projection means, and FIG. 7 is a diagram showing the control operation on the beam light projection means side. Flow chart, FIG. 8 is a perspective view of the entire vehicle body, FIG. 9 is a block diagram of the control configuration on the vehicle body side, FIG. 10 is an explanatory diagram of light receiving position determination, FIG. 11 is a flow chart of control operation on the vehicle body side, and FIG. The figure is a front view showing the positional relationship between the projection position of the guiding beam light and the light receiver on the vehicle body side in another embodiment. (A)...Guiding beam light, (V)...
・Vehicle body, (Sυ, (5ri = ... light receiving means, (T
+) , (T2) ”--time, (1)... Beam light projection means, (100)... Steering control means, (101)... Time measurement Means, (101)・
...Position determination means.

Claims (1)

[Claims] 1. A beam light projection means (1) for projecting a guiding beam light (A) onto the ground side at a set scanning angle and at a set scanning speed along the traveling direction of the vehicle body (V). and guide beam light (A
) is provided to repeatedly scan the vehicle body (
V), a light receiving means (S_1) whose light receiving position of the guiding beam light (A) changes as the position changes in the width direction of the vehicle body;
), (S_2) and its light receiving means (S_1), (S_2
) A work vehicle guidance device using beam light, comprising a steering control means (100) for controlling the steering so that the vehicle body (V) travels along a set travel trajectory based on the light reception position information of the vehicle body (V). A position detection device in which the light receiving means (S_1) and (S_2) receive the guiding beam light (A).
A time measuring means (101) for measuring the time (T_1 or T_2) from the moment when the light is received until the next light is received, and based on the information of the time measuring means (101), the time in the length direction of the set traveling trajectory is A position detecting device in a working vehicle guiding device using beam light, which is provided with a position determining means (102) for determining the position of the vehicle body (V). 2. The position determining means (102) detects two times (T_1) successively measured by the time measuring means (101).
), (T_2), the position detection device in a work vehicle guiding device using beam light according to claim 1, wherein the position detection device is configured to determine the position of the vehicle body (V) based on the ratio of (T_2).