JP2727376B2 - Mobile vehicle stop position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a station in which a mobile vehicle travels automatically, provided with a reference member for displaying reference position information in plan view,
Determining the amount of deviation of the moving vehicle from the setting proper stop state of the moving vehicle with respect to the station based on information read by an imaging device that reads display information of the reference member from a working device that works on the station with the moving vehicle; The present invention relates to a stop position detecting device for a mobile vehicle attached to the work position so that the imaging device is automatically moved to the reading setting position of the reference member by the work device.

[Conventional technology]

Conventionally, this kind of moving vehicle stop position detecting device is designed to ensure that the display information of the reference member can be read even when the moving vehicle stops in a state where it is largely out of the setting proper stop state with respect to the station. In order to satisfy the requirement of accurately detecting the shift amount from the proper stop state, the shift amount is detected while changing the imaging field of view of the imaging means to be wide or narrow (Japanese Patent Application No. 1-8305).
No. 8).

To add an explanation, the imaging unit is configured to be able to change its imaging field of view to be wide and narrow, and based on imaging information of the imaging unit in the state where the imaging field is widened, the position shift amount of the reference member with respect to the center of the visual field is determined. Determining means for determining, and correcting means for moving the imaging means in the horizontal direction such that the reference member is located on the center side of the field of view based on the information of the determining means are provided;
The apparatus is configured to determine the displacement amount based on imaging information of the imaging unit in a state where the imaging field of view is narrowed.

In other words, this conventional means has a point that the reference member can be reliably recognized in a wide imaging field of view even if the deviation amount from the setting appropriate stop state of the moving vehicle is large, and in a narrow imaging field of view,
In view of the fact that the reference member can be recognized with high resolution and the amount of displacement can be detected with high accuracy, the amount of displacement is detected while changing the imaging field of view of the imaging means to a wide or narrow range. By the way, by using an image pickup means capable of recognizing the reference member with high resolution even in a wide image pickup field, it is possible to omit changing the image pickup field to a wide or narrow area, but such an image pickup means is expensive and is not practical. It is difficult to do.

[Problems to be solved by the invention]

However, in the above-described conventional technology, the imaging means has a complicated structure and a large weight because the imaging field of view can be changed to be wide and narrow. When the weight of the imaging device increases, the load on the working device increases, and it is necessary to make the working device durable even if the articles handled by the working device are light in nature. There is a drawback that a large driving energy is required to move the working device.

In order to avoid such disadvantages, the following alternative means can be considered.

That is, a plurality of the reference members are provided at a predetermined distance from each other, and the working device automatically moves the imaging unit to a plurality of reading setting positions defined corresponding to each of the plurality of reference members. The deviation amount determination means is configured to determine the deviation amount based on a plurality of pieces of read information read by the imaging means for each of the plurality of reference members.

This different means obtains the displacement amount of the vehicle body from the read information of a plurality of reference members separated by a distance, so that, for example, when detecting the inclination when the moving vehicle is tilted and stopped with respect to the set proper stop state, By determining the inclination by also using the positional relationship of each reference member in plan view, the detection accuracy can be improved without recognizing each reference member with high resolution. As a result, the imaging means The working device in the above-described conventional means using a heavy imaging means must be made robust for the imaging means so that the displacement amount can be accurately detected while using a simple and lightweight one having a wide field of view. It is possible to avoid disadvantages and disadvantages that require large energy to drive the working device.

However, since it takes time to move the image pickup means to a plurality of reading setting positions defined corresponding to each of the plurality of reference members provided at a predetermined distance, detection can be speeded up. There was a disadvantage that it could not be realized.
In other words, this separate means requires that a plurality of reference members be provided as far apart as possible in order to enhance the detection accuracy, and therefore, the time required for the movement of the imaging means becomes longer, and the It is difficult to speed up.

The present invention has been made in view of the above circumstances,
Its purpose is to make it possible to use a simple and lightweight imaging means while suppressing a decrease in detection accuracy, and furthermore, to shorten the detection time to achieve a quicker detection position of a mobile vehicle. It is to provide a detection device.

[Means for solving the problem]

In order to achieve this object, a first characteristic configuration of the moving vehicle stop position detecting device according to the present invention is as follows. A reference member provided at a station where the moving vehicle automatically travels and displaying reference position information in plan view is provided. A plurality of element parts which are two-dimensionally dispersed and arranged, each of which is configured to display information for specifying a position of the reference member with respect to the entirety of the reference member; Is configured to automatically move the imaging unit to the reading setting position of the reference member, based on the display content of the element unit in the reading information of the imaging unit moved to the reading setting position. Correction position determination means for determining a correction position at which the imaging means should be moved to determine the amount of deviation of the moving vehicle from the station from the setting proper stop state with respect to the station. The working device is configured to move the imaging unit to the correction position, and the shift amount determination unit for determining the shift amount is read information of the imaging unit moved to the correction position, or The shift amount is determined based on the information and the read information of the imaging unit moved to the read setting position.

Further, the second characteristic configuration specifies a preferred specific configuration when the first characteristic configuration is implemented, and the element portion is located at a central portion of the reference member and an outer peripheral portion thereof. The correction position determination unit is distributed and arranged so that the correction position determination unit captures two element portions of the outer peripheral portion that are opposed to each other across the center portion of the reference member among the element portions included in the reference member. It is characterized in that a position is determined as the correction position.

(Operation)

According to the first characteristic configuration, in a state where the moving vehicle is stopped with respect to the station, first, the working device provided with the image pickup means is operated to read the image pickup means corresponding to the reference member provided on the station side. The display information of the reference member is read by the image pickup means. Next, based on the display content of the element portion in the read information, a correction position at which the imaging means should be moved to determine the amount of displacement is determined, and the imaging means is automatically moved to the correction position. Then, the display information of the reference member is read. Then, based on the read information at the correction position, or the information and the read information at the read setting position, the amount of deviation of the mobile vehicle from the set proper stop state with respect to the station is determined.

In the case of detecting the shift amount in this way, the above-described method is used so that the information of the reference member can be reliably read even when the shift amount of the stop position of the moving vehicle is large, using a narrow-field imaging unit having a high reading resolution. The reference member includes a plurality of two-dimensionally dispersed element parts, and each of the element parts is configured to display information for specifying its own arrangement position with respect to the entire reference member.

For this reason, by reading any one of the element portions of the reference member at the reading setting position, the correction position for determining the positional deviation can be determined.

Since the reading operation at the correction position and the reading setting position is performed by using a narrow-field imaging unit, the accuracy of detecting the amount of displacement can be improved, and the correction position at which the imaging unit is moved is Since it corresponds to the element part in the reference member, the moving distance for moving the imaging means is short, and therefore, the moving time is short, and the detecting operation can be performed quickly.

According to the second characteristic configuration, of the element parts dispersedly arranged at the central part of the reference member and the outer peripheral part thereof, two element parts of the outer peripheral part opposed to each other with the central part of the reference member interposed therebetween are used. Two positions for imaging are determined as the correction positions, the imaging unit is moved to the determined two correction positions, and a shift amount is determined at each correction position based on information read by the imaging unit. Will be. in this case,
If the two correction positions are set for two element parts that are located far apart from each other among a plurality of element parts, it is effective to further improve the detection accuracy.

〔The invention's effect〕

Therefore, according to the first characteristic configuration, the amount of displacement can be detected accurately and reliably while using a simple and lightweight imaging device having a narrow field of view. In the means, it is possible to avoid the disadvantage that the working device must be made robust for the imaging means and the disadvantage that requires a large amount of energy to drive the working device, and furthermore, the detection operation can be speeded up. This has resulted in a mobile vehicle stop position detecting device which is advantageous in terms of practical production and actual operation.

Further, according to the second characteristic configuration, in addition to the effects of the first characteristic configuration, it is possible to further improve the detection accuracy.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 2 and FIG. 4, a work station is provided on a lateral side of a traveling path of a mobile vehicle (A) on which a load transfer manipulator (1) as a work device is mounted. A plurality of load transfer stations (ST) are installed. Then, as the mobile vehicle (A) stops at the designated station (ST), the load (N) is transferred between the station (ST) and the mobile vehicle (A) by the manipulator (1). The loading work is configured to be performed automatically.

Although not described in detail, the load (N) transferred to the moving vehicle (A) at one station (ST) is unloaded at another station (ST) or processed at the station (ST). Every time the work etc. is completed, it is transferred to the moving vehicle (A) again,
It will be transported to the next station (ST).

However, the moving vehicle (A) is configured to autonomously travel between stations (ST) without using a traveling guide or the like. The station (ST) when stopped at the station (ST) will be described in detail later.
, The amount of displacement (Y) in the vehicle width direction with respect to the reference position in plan view, the amount of displacement (X) in the vehicle longitudinal direction, and
The travel route to the next station (ST) can be automatically corrected based on each deviation amount information of the inclination (θ) in the vehicle longitudinal direction (see FIG. 5).

In the drawing, the stationary reference coordinate axes (hereinafter, referred to as layout coordinate axes) of the traveling control system for a mobile vehicle to which the present invention is applied are X ″, Y ″ axes, and reference coordinate axes fixed to the mobile vehicle (A). The X-axis is defined as the vehicle longitudinal direction, and the Y'-axis is defined as the vehicle width direction. And the center (AC) of the moving vehicle (A)
Is the origin of the X ', Y' coordinate axes, and the moving vehicle (A)
In the case of stopping in the proper stop state for the station (ST), the center (AC) coincides with the reference position (LC) on the layout coordinate axis, the X ″ axis and the X ′ axis are parallel, and Y The "axis and the Y 'axis are parallel.

The traveling route between the stations (ST) will be further described. As shown in FIG. 4, the vehicle longitudinal direction of the moving vehicle (A) is set as the X ″ axis, and the vehicle width direction is set as the Y ″ axis. I have. And two stations (ST
₁ ) and (ST ₂ ), based on the distance (l ₁ ) in the X ″ axis direction and the distance (l ₂ ) in the Y ″ axis direction between the (ST ₂ ) and the normal route for autonomously traveling the mobile vehicle (A). The information of (L ₀ ) is set and stored in advance. However, the moving vehicle (A) is different from one station (ST ₂ ) to the other station (ST ₁ ).
It is assumed that the vehicle travels toward.

The normal route (L ₀ ) is a straight line section (T ₁ ), (T ₂ ), (T ₃ ) divided into a plurality of straight lines connecting the two stations (ST ₁ ) and (ST ₂ ). The respective distance information, the turning radii (R ₁ ), (R ₂ ) and the turning angle (θ ₁ ) for changing the direction at the connection point of each straight section (T ₁ ), (T ₂ ), and (T ₃ ) , (Θ ₂ ), and the distance information and the turning angle information are previously mapped and stored as travel control information for the mobile vehicle (A).

That is, the moving vehicle (A) moves from the one station (ST ₂ ) to the other station (ST ₁ ) on the basis of the stored traveling control information in the straight sections (T ₁ ) and (T ₁ ).
The vehicle travels autonomously while turning the set angle at the set radius at the connection point of each section so that (T ₂ ) and (T ₃ ) go straight in that order, and automatically stops at the next station (ST ₁ ) They are able to do that.

In FIG. 4, (r ₁ ) and (r ₂ ) are distances between the stations (ST ₁ ) and (ST ₂ ) and the regular route (L ₀ ) in the vehicle width direction.

As shown in FIGS. 1 and 2, when the mobile vehicle (A) stops at the designated station (ST), the station (ST)
The moving amount of the moving vehicle (A) from the setting proper stop state is detected to automatically correct the operation amount of the manipulator (1), or the moving vehicle (A) is directed to the next station (ST). A reference member (3) for displaying reference position information for the station (ST) is provided in order to automatically correct a traveling route when the vehicle travels.

FIGS. 6A and 6B show the reference member (3).
As shown in the figure, an element mark (3C) as an element part for displaying information for specifying a self-placed position with respect to the entirety of the reference member (3) is provided at a center point (0 ') of the reference member (3). ) (Hereinafter, may be referred to as a center or a center position for the sake of description). In the figure, the X axis is the longitudinal direction of the vehicle body,
The axis is the vehicle width direction, and the center point (0 ') is the origin of the X and Y coordinates. Further, each element mark (3C) is arranged on a straight line connecting the centers of gravity of three circles having different diameters (large circle, middle circle, small circle), and at a predetermined distance in the order of size, In addition, the center point (0 ') is configured to be located at a predetermined distance on the side having a smaller diameter on the extension of the straight line.

In addition, in the center of the reference member (3), address information given in advance is displayed at the same time to identify which station (ST) the mobile vehicle (A) is stopped at. It is configured as follows.

As shown in FIG. 6 (C), the reference member (3)
A sheet-shaped prism-shaped light reflector (3a) that totally reflects incident light in the incident direction is formed to a set size, and a black matte-coated resin flat plate (3b) is adhered to the surface. It was done. Incidentally, FIG. 6 (C) corresponds to X in FIG. 6 (A).
The section along the axis is shown.

The black plate (3b) has the station (ST)
, Four reference position marks (a) to (d) for displaying reference position information, and a plurality of address marks (e) to (e) for displaying the address information in the form of a binary code.
(L) and a plurality of through holes of the same diameter forming respective three types of marks, parity marks (m) to (p) for the address marks (e) to (l), are arranged in a predetermined arrangement. It is formed as follows. That is, the reference member (3) is formed so that only the portion where the marks (3C) and (a) to (p) are formed is reflected and looks brighter than the surroundings.

Here, the intersection point of the line connecting the centers of gravity of the four reference position marks (a) to (d) diagonally coincides with the center point (0 ') of the reference member (3). ing. Therefore, the four reference position marks (a) to (d) indicate information for specifying the self-placement position with respect to the entire reference member (3) at the center of the reference member (3). Therefore, the element portions are dispersedly arranged at the central portion of the reference member (3) and the outer peripheral portion thereof, that is, the element mark (3C).

Further, in order to facilitate recognition of which mark, the four reference position marks (a) to (d) are centered on the center point (0 ') of the reference member (3). Each one is located at each vertex of the square, and the address marks (e) to
(L) is a state in which the inside of the reference position marks (a) to (d) is divided into an upper part and a lower part in the X-axis direction along the vehicle longitudinal direction, and the Y-axis direction along the vehicle width direction. And the parity marks (m) to (p) are arranged so as to be aligned with the address marks (e) to (l).
They are arranged so as to be located on the respective lateral sides in the X-axis direction.

The reading of the marks (3c) and (a) to (p) and the determination of the read information will be described later.

As shown in FIGS. 1 and 2, the moving vehicle (A)
Are provided at a pair of left and right propulsion wheels (6) provided substantially at the center in the front-rear direction of the vehicle body and at respective front and rear end portions of the vehicle body in a state in which the pair of electric motors (5) are individually driven to stop and reversely rotate. And a pair of left and right idler wheels (7). That is, the moving vehicle (A) is configured to be able to change its direction on the spot.

The moving vehicle (A) is equipped with an optical fiber type gyro device (Sb), and detects a deviation of the traveling direction with respect to the regular route (L ₀ ) based on information of the gyro device (Sb). Thus, the pair of electric motors (5) are steered by changing the speed so that the rotational speeds of the pair of left and right propulsion wheels (6) are different.

In FIG. 1, (Sc) is a contact wheel type traveling distance detection sensor provided at a location that is a turning center of the pair of left and right propulsion wheels (6).

As shown in FIG. 3, between the ground-side central control device (8) that manages the operation of the mobile vehicle (A) and the mobile vehicle (A), destination information of the mobile vehicle (A) and the like. Wireless communication devices (9a) and (9b) for communicating various information such as operation command information of the manipulator (1) are provided on the mobile vehicle (A) and on the ground side. The ground-side communication device (9b) is connected to the central control device (8),
A communication device (9a) on the moving vehicle side includes a microcomputer-based moving vehicle controller (M) mounted on the moving vehicle (A) for controlling the traveling of the moving vehicle (A) and the operation of the manipulator (1). 10) Connected to.

In FIG. 3, (11) denotes an image sensor (Sa) described later.
An image processing unit that performs image processing on the image pickup information and transmits information on the reference member (3) to the mobile vehicle controller (10);
(12) is a manipulator controller that controls the operation of the manipulator (1) based on a command from the mobile vehicle controller (10), and (13) is the left and right propulsion wheels (6).
A traveling controller for controlling the operation of a traveling motor (5) for driving the vehicle; (14) the traveling controller (13);
A driving device for driving the traveling motor (5) based on the instruction of (5). (15) is a device for manually setting destination information for the moving vehicle (A) and performing various operations to recover from an emergency stop or the like. A setting device for manually setting information.

The manipulator (1) will be described in the form of a so-called articulated type as shown in FIGS. 1 and 2, and a load gripper (2) is provided at its tip.
And a two-dimensional image sensor (Sa) as imaging means for reading display information of the reference member (3). Although not described in detail, the manipulator (1)
Is operated based on information on an encoder for detecting the amount of operation of the electric motor provided in each joint and various kinds of control information stored in advance to perform a load transfer operation. .

Next, a description will be given of stop position detection for detecting a deviation amount (X, Y, θ) from a setting appropriate stop state of the mobile vehicle (A) in a state where the mobile vehicle (A) is stopped at the station (ST).

The manipulator (1) moves the two-dimensional image sensor (Sa) to a reading set position corresponding to the reference member (3) based on a command from the manipulator controller (12).
Is automatically moved. Here, based on the display content of the element mark (3C) or the reference position marks (a) to (d) in the read information obtained by the image sensor (Sa) reading the reference member (3), A correction position determining means (101) configured by using a moving vehicle controller (10) and an image processing unit (11) determines a displacement amount (X, Y, θ) by using a two-dimensional image sensor (Sa). Is determined, and then the two-dimensional image sensor (Sa) is automatically moved to the corrected position to read the display information of the reference member (3).

Then, a shift amount discriminating means (100) configured by using the moving vehicle control (10) and the image processing unit (11).
Is read information read by the two-dimensional image sensor (Sa) at the correction position, or read information read by the two-dimensional image sensor (Sa) at a read setting position corresponding to this information and the reference member (3). Is configured to determine the deviation amount (X, Y, θ) based on
The two-dimensional image sensor (Sa) is configured to have a narrow imaging field of view so as to read the reference member (3) with high resolution, and has a coordinate axis on the image of the two-dimensional image sensor (Sa).
Each of x and y is configured to be parallel to the coordinate axes X ′ and Y ′ of the moving vehicle (A).

The operation procedure of the displacement detection will be described with reference to FIGS. 7 to 9. First, the manipulator (1) is operated with an operation amount stored in advance and the image sensor (Sa) is set as a reference. The member is moved to the reading set position corresponding to the member (3).

Usually, since the error due to autonomous traveling is not 0, the XY axis of the reference member (3) does not match the xy axis of the imaging field of view of the image sensor (Sa), and the origin (0 ') And the origin (G) of the xy axes are also shifted (see FIG. 7). In the state shown in the figure, the image sensor (Sa) is a narrow-field imaging unit, and the position shift is large.
Indicates that the center position (0 ') is not within the imaging field of view, but one element mark (3C) is captured.

Here, the imaging signal from the image sensor (Sa) is input to the image processing unit (11), and is binarized based on the contrast of the imaging signal, and then the element mark (3C) within the imaging field of view. Is output as coordinate detection information for the entire reference member (3).

7, among the three circles forming the element mark (3C), the center of gravity of the largest circle is P, and the center of gravity of the smallest circle is R.

As described above, the center (0 ') of the reference member (3) is on the extension line connecting the point P and the point R, and is a line segment parallel to the x-axis and passing through the point O' and a point P parallel to the y-axis. If the intersection of a line segment passing through is Q, a right triangle is formed at three points O ′, P, and Q. The line segment O'P
And the angle between the y axis and theta _P, the gravity center position P of the circle, the coordinates in the x-y coordinate axis R respectively (x _1, y _1), and (x _2, y _2).

Next, the information of the image processing unit (11) is input to the mobile vehicle controller (10).

From the figure, And the coordinate value (x ₀ ,) of the center (0 ′) of the reference member (3) on the screen coordinate axis xy of the image sensor (Sa).
y ₀ ) is obtained by the following equation.

_{x 0 = O'Q + x 1 =} O'Psinθ P + x 1 y 0 = QP + y 1 = O'Pcosθ P + y 1 Here, since the segment O'P is predetermined on configuration of the reference member (3), the The coordinate value (x ₀ , y ₀ ) is determined as a specific detection information amount.

Next, the coordinate value (x ₀ , y ₀ ) of the center (0 ′) of the reference member (3) is used. 2 of the outer peripheral portions that are arranged at equal distances that are already set, that is, opposed to each other across the central portion of the reference member (3) among the element portions.
Two positions for imaging the three element marks (3CL) and (3CR) are determined as correction positions, and a reference member (3) for imaging these correction positions and the marks (a) to (p). A correction amount for operating the manipulator (1) at a position where the center (0 ') of the image overlaps the center (G) of the imaging field of view is obtained.

The image sensor (Sa) is moved by operating the manipulator (1) by the distance corresponding to the correction amount, and the element mark (3CL) → marks (a) to (p).
→ The image is taken by moving in parallel on the x-axis of the field of view in the order of the element mark (3CR). A screen in which the element mark (3CL) is imaged by the image sensor (Sa) is defined as an imaging field of view (S _L ), and a screen in which the element mark (3CR) is imaged is defined as an imaging field of view (S _R ).
See figure). Note that the order of imaging the imaging visual field (S _L ) and the imaging visual field (S _R ) can be arbitrary. FIG. 10 (A) shows an image of the marks (a) to (p).

Here, a method of obtaining a deviation angle of the mobile vehicle (A) from the station (ST) in the vehicle longitudinal direction will be described with reference to FIG. In each field of view (S _L ), (S _R )
Element marks (3CL), for detecting the position of (3CR), for example, to detect the position of the center of gravity of the largest circle, respectively the coordinates (x _3, y _3), and (x _4, y ₄₎ . Also the element mark (3C
An angle between a straight line (X axis) connecting L) and (3CR) and the screen coordinate x axis is defined as θ. Here, element mark (3CL), (3C
Since the distance (L) between R) is predetermined in view of the configuration of the reference member (3), the inclination θ is obtained as in the following equation.

On the other hand, the X axis corresponding to the vehicle longitudinal direction of the reference member (3) is attached so as to be parallel to the layout coordinate axis X ″ axis corresponding to the vehicle longitudinal direction of the station (ST). The x-axis corresponding to the direction is configured so as to be parallel to the X′-axis corresponding to the vehicle longitudinal direction of the coordinate axis fixed on the vehicle body (A). ) Is given by θ.

Also, as described above, the coordinate value of the center (AC) of the moving vehicle (A) can be obtained by moving the image sensor (Sa) to the reading set position by the predetermined operation amount. The center position of the imaging screen and the center of the moving vehicle (A) (A
Since the arrangement relationship of C) is determined, the reference member (3)
The coordinate value (x ₀ , y ₀ ) corresponding to the distance between the center (0 ′) of the image and the center position of the imaging screen can be obtained by performing coordinate conversion as a correction amount, and finally the reference stop on the layout coordinate axis The shift amount (X, Y) corresponding to the difference between the coordinates of the position (LC) and the center position (AC) of the moving vehicle (A) can be obtained.

Therefore, by correcting the operation amounts of the respective joints which are set and stored in advance based on the values of the deviation amounts (X, Y) and the values of the inclinations (θ), when the moving vehicle (A) stops, Even if the posture of the load (N) deviates from the state of proper stop with respect to the station (ST), the load (N) in which the load gripper (2) of the manipulator (1) is at a predetermined position with respect to the reference member (3). Can be properly grasped.

Further, on a screen for imaging the marks (a) to (p),
The address marks (e) to (l) and the parity marks (m) to (p) to be read are defined by their sizes and the reference position marks (a) to (p) stored in advance.
From the positional relationship with respect to (d), the address marks (e) to (l) and the parity marks (m) to
The presence / absence of (p) is determined, and based on the combination of the presence / absence of the mark, the address of the station (ST) where the moving vehicle (A) is currently stopped is determined.

Then, as the load transfer operation is completed, the next station (ST) stored in advance or instructed by the central control device (8) via the communication devices (9a) and (9b). And the reference stop position (L
Deviation (X, Y) of the center (AC) of the moving vehicle (A) with respect to C)
Then, based on the information on the inclination (θ), the traveling direction for traveling to the next station (ST) is corrected to start the automatic traveling.

To explain the correction of the traveling direction, as shown in FIG. 5, the moving vehicle (A) is connected to the station (ST).
Assuming that the vehicle is stopped in a state where there is a positional shift and a tilt in a direction approaching the, firstly, the shift amount (X, Y)
Based on the value of and the value of the inclination (θ), within a range where the moving vehicle (A) does not collide with the station (ST),
The maximum angle (θs) that can be changed in the direction of the normal route (L ₀ ) stored and stored, and the travel distance (Ts) to the contact point (0) with the normal route (L ₀ ) are obtained. The gyro device (Sb) is reset, and information on the detected traveling direction is initialized.

Next, based on the information of the gyro device (Sb), the left and right propulsion wheels (6) are reverse-rotated to spin-turn on the spot, and the inclination (θ) and the maximum changeable angle ( θs) is changed in the direction of the regular route (L ₀ ), and the traveling distance (Ts) is calculated at a low speed based on information from the traveling distance detection sensor (Sc). ) To travel straight ahead and stop at the contact point (0) with the regular route (L ₀ ). Thereafter, the maximum angle (θs) is changed to the station side by a spin turn, and the vehicle travels to the next station (ST) while traveling autonomously along the regular route (L ₀ ) at a set speed. It will start running.

After the automatic traveling is started along the regular route (L ₀ ), as described above, the left and right propulsion wheels (6) are operated with a difference in rotation speed based on the information of the gyro device (Sb). The vehicle (A) on the regular route (L ₀ ) based on the information of the traveling distance detecting sensor (Sc).
Automatic stop will be performed when reaching T).

(Another embodiment)

In the above embodiment, at the reading set position corresponding to the reference member (3), the correction position for the position deviation determination is determined based on the information obtained by the image sensor (Sa) reading the reference member (3). Thereafter, as a next operation, the manipulator (1) is operated to move the image sensor (Sa) to the correction position and a position where the center (0 ') of the reference member (3) and the center (G) of the imaging visual field overlap each other. Although the shift amount is detected, a different method from the above can be used in such an operation, and modifications of these operations will be described below.

Another operation example (1) (see FIGS. 10 (A) and (B)) In this embodiment, first, the corrected position determination means (101)
Given by the coordinate amount (x ₀ , Y ₀ ) corresponding to the distance between the center position of the screen of the image sensor (Sa) and the center position (0 ′) of the reference member (3). ) To move the image sensor (Sa) to the center position (0 ') of the reference member (3).

Normally, the center position of the screen and the center position (0 ') of the reference member (3) do not completely coincide with each other due to an error in measuring the screen of the image sensor (Sa) or an error in operating the manipulator (1). (See FIG. 10 (B)).

Here, the coordinate values on the screen coordinates x-y axes of the intersections of the line segments connecting the centers of gravity of the four reference position marks (a) to (d) captured by the image sensor (Sa) diagonally. (Δx, Δy) is detected and added to (x ₀ , y ₀ ) obtained from the screen measurement of the element mark (3C), thereby obtaining a shift amount from the center of the reference member (3) to the center of the screen coordinates. it is possible to improve the detection accuracy of (the same (x _10, and y ₁₀₎₎ and the amount of deviation of the stop position of the transport vehicle (a) to determine on the basis of this (X, Y). In FIG. 10 (B), address marks and the like (e) to (p) are omitted for explanation. It can be expressed by the following expression.

Next, on the same screen, the address marks (e) to (l) to be read and the parity mark (m) to
(P) is calculated based on their size and the positional relationship with respect to the reference position marks (a) to (d), which are set and stored in advance, from the address marks (e) to (l) and the parity marks (m) to (m). (P), and based on the combination of the presence or absence of the mark, the moving vehicle (A)
Will determine the address of the currently stopped station (ST).

Then, in order to detect the angle shift, as described above, the correction positions corresponding to the element marks (3CL) and (3CR) located in the X-axis left-right direction from the center position (0 ') of the reference member (3). Then, the image sensor (Sa) is moved and the deviation angle of the vehicle body (A) with respect to the station (ST) is obtained from the read information there as θ (see FIG. 9).

Here, if θ = 0 °, the relationship between the displacement amounts (x ₁₀ , y ₁₀ ) and (X, Y) is as follows.

_{x 10 = X, y 10 =} Y another operation example (2) (a 10 (A), (B), (C) see Figure) First, the coordinate amount by the same operation as another operation example of the above (1) The manipulator (1) is operated by (x ₀ , y ₀ ) to move the image sensor (Sa) to the center position of the reference member (3). The screen here is the field of view indicated by S2 in FIG. 10 (C). Note that S1 is the imaging field of view before the movement.
In the S2 field of view, the four reference position marks (a) to
The deviation (Δx ₁ , Δy ₁ ) between the intersection of the line segment connecting the center of gravity position diagonally and the screen coordinate center and the deviation angle between the coordinate axis of the reference member (3) and the screen coordinate axis are θ = θ _3. Asking. It is shown by the following equation.

Next, an image sensor (Sa), around its screen coordinate origin, rotated by the deviation angle theta _3, further shift amount (Δx _1, Δy ₁₎ minute moved in parallel.

Then, the imaging field of view becomes S3 in FIG. 10 (C). Usually, even at this stage, due to the measurement and operation errors described above,
The center of the screen is offset from the center of the reference member (3), and the coordinate axes are not parallel.

In the state of S3, the shift amounts (Δx ₂ , Δy ₂ ) are obtained in the same manner as described above.

By adding the detection values obtained in the process of correcting the displacement as described above, the displacement from the center of the reference member (3) to the center of the screen coordinates (this is (x ₂₀ ,
y ₂₀ )), so that the stop position deviation amount (X, Y) of the vehicle body (A) with respect to the station (ST) determined based on this is accurately detected.

_{x 20 = x 0 + Δx 1} + Δx 2 y 20 = y 0 + Δy 1 + Δy 2 also can be performed to read the detection of such address mark in the same manner as the further operation example (1).

Next, in order to detect the angle shift, as described above, the correction position corresponding to the element marks (3CL) and (3CR) in the X-axis left-right direction from the center position (0 ') of the reference member (3) is set. moves manipulate image sensor (Sa), from information read therein, determine the deviation angle theta ₄ between the X coordinate axis and the screen coordinates x-axis of the reference member (3) (see FIG. 9). However, reread the θ in the figure and θ _4. After all, the station (S)
The shift angle with respect to T) is obtained by θ = θ ₃ + θ ₄ .
Here, the initial angular misalignment theta ₃ as described above in operation of rotating the image sensor (Sa), since the modified, the theta ₄ has become a value close to 0. For this reason,
Even when the angle shift amount is processed based on the screen coordinate value, the angle shift amount can be processed in an imaging region with less screen distortion, so that accurate results can be obtained. Also, should the angle shift be abnormally large,
When the image sensor (Sa) is moved to the correction position for detecting the displacement, the detection operation can be performed without protruding from the imaging field of view.

If θ = 0 °, the deviation amounts (x ₂₀ , y ₂₀ ) and (X, Y)
The relationship is as follows.

x ₂₀ = X, y ₂₀ = Y Another operation example (3) This embodiment is the same as the above-described other embodiment until the image sensor (Sa) is moved from the reading set position to the mark center position. After that, the reference position marks (a) to (d) at the center position are detected to determine the amount of displacement and the displacement angle (FIG. 10A,
(B)).

Since a high-resolution, narrow-field image sensor (Sa) is used, this simple method is also possible.
In addition, reading of address marks (e) to (p) can be similarly performed.

Further, in the above-described embodiment, as shown in FIG. 6, the reference member (3) is exemplified by one type of element mark (3C). However, as the element mark (3C), the reference member (3C) is used. It suffices to display information that allows the user to specify his or her own arrangement position with respect to the entirety. Hereinafter, a configuration example of another reference member (3) will be described (FIGS. 11A to 11D, FIG.
12 (A) to (E).

FIGS. 11A to 11D show modified examples of the element mark composed of a combination of circles, and there are three types of element marks. For example, in FIG. 11B, the centers of three small circles are arranged on a straight line at a predetermined distance, and this straight line is parallel to the X-axis. The great circle and the center of the reference member (3) are located at a predetermined distance on a line passing through the center of the small circle. The center of the reference member (3) is the origin of the XY coordinates, and is located at equal distances on both sides in the Y-axis direction with respect to the center of the reference member (3). FIG. 11 (C) shows that three small circles and one great circle are arranged at each vertex of a square, and a reference member is placed on the extension of the straight line connecting the great circle and the small circle at diagonal positions on the great circle side. The center of (3) is positioned, and the angle between this straight line and the XY coordinate axis is 45 °. The element marks in FIG. 11C have four sides arranged parallel to the XY axis and four centers at each vertex position of a square at the origin of the XY coordinates. FIG. 11D shows a great circle,
One circle each of a middle circle and a small circle is arranged on a straight line parallel to the X axis in the order of its size, and at a predetermined distance on an extension of the small circle on this straight line, the origin of the XY axis, that is, The center of the reference member (3) is located, and two of these marks are arranged at equal distance positions on the X axis on the left and right. In the center of the mark,
The reference position marks and the like (a) to (p) are arranged.

Next, image processing for determining the correction position from the read information of the mark diagrams (B) to (D) will be described. In FIG. 11B, the diameters of the four circles are identified, the positions of the centers of gravity are detected, and the center direction and center position of the reference member (3) are obtained.

In the case of FIG. 11C, the diameters of the four circles are identified and the positions of the centers of gravity are detected, and the center direction and center position of the reference member (3) are obtained. 11D detects the diameter and the position of the center of gravity of each circle, and determines the center direction and center position of the reference member (3) in the direction of the small circle.

Then, in order to detect the position shift angle from the read information at the correction position, for example, by detecting the position of the center of gravity of the great circle in FIG. 9).

In addition, the image sensor (S
In the field of view obtained by imaging the reference member (3) according to a),
When there are more than two types of element marks, the priorities of mark discrimination can be set, for example, as shown in FIGS.
In the order of (D), the accuracy of position detection can be improved by using an element mark closer to the center of the reference member (3).

Another embodiment of the configuration of the reference member (3) is shown in FIG.
This will be described with reference to (A) to (E). In this example, a rectangle and a small circle are combined. FIG.
(B) is a parallelogram having long and short diagonal lines, the center of gravity of which is located at the center of the reference member (3), the long diagonal direction is the X axis, and the short diagonal direction is Y. Axis.

In FIG. 12 (C), the length from the barycentric position of the rectangle to each corner is one that is longer, and the lengths to the other three corners are the same. The straight line extending from the position of the center of gravity to the longer corner is the Y-axis, and the center of the reference member (3) is located on the extension of this straight line. Then, this mark is located at two equal distances above and below the Y axis.

The one shown in FIG. 12D is a combination of the square and the small circle in FIG. 12C, and the small circle is drawn on a straight line connecting the position of the center of gravity of the square and the long corner having a long length to the corner. , Is configured to be on the opposite side of the long corner to the corner.

The straight line connecting the center of gravity of the rectangle and the small circle is the mark coordinate axis.
An angle of 45 degrees is formed with respect to the X and Y axes, and the origin of the XY coordinates, that is, the center of the reference member (3) is located on the extension of the straight line on the side opposite to the small circle.

Four such marks are located at each vertex position of a square centered on the reference member (3). FIG. 12E shows a combination of a square and a small circle. And
One diagonal of the square is parallel to the X-axis, and on the extension of this straight line is the center of gravity of the small circle, and on the opposite side of the small circle is the center of the reference member (3).

The two marks are located at equidistant positions on the left and right of the X axis.

Next, image processing for determining a position shift and a correction position based on the read information of the mark diagrams (B) to (E) will be described. In FIG. 12B, the center position of the reference member (3) can be obtained by detecting the position of the center of gravity of the square. Further, the direction of the diagonal of the quadrangle can be detected, and the deviation angle can be obtained. In FIG. 12C, the center direction and position of the reference member (3) are obtained by identifying the position of the center of gravity of the rectangle and the length and direction of the diagonal line. In FIG. 12D, the position of the center of gravity of the quadrangle, the straight line connecting the center of gravity of the square and the center of the small circle are detected, and the center direction and position of the reference member (3) are obtained. In FIG. 12E, the center of gravity of the square and the center of gravity of the small circle are detected, and the center direction and position of the reference member (3) are obtained.

Next, in order to detect the angle of displacement from the read information at the correction position, for example, by detecting the center of gravity of the small circle in the mark in FIG. (See FIG. 9).

In addition, the image sensor (S
When there are two or more types of element marks in the field of view obtained by imaging the reference member (3) according to a), priorities for mark discrimination can be given. For example, FIG.
In the order of (C), (D), and (E), the reference member (3)
The accuracy of position detection can be increased by using an element mark closer to the center of the position.

Next, a modified example of a method of transferring a load (N) to the station (ST) using the manipulator (1) of the vehicle body (A) will be described.

In the example described so far, the direction of transfer of the load (N) is as shown in FIG.
And as shown in FIG. 4, the station is only in one direction. However, when the reference member (3) having the configuration of the present invention partially captures the reference member (3),
Since it is configured to be able to specify its own arrangement position with respect to the whole, it is possible to transfer the load (N) from multiple directions (see FIG. 13).

In the figure, the positions of three moving vehicles (A) A ₁ , A ₂ , and A ₃ are shown, and one moving vehicle (A) transfers a load (N) from three directions. Showing things. Here, C is a mounting center of the manipulator (1), (16) is a load (N) conveyor, and (17) is a stocker.

Incidentally, A ₂ is the moving vehicle (A) is also assumed when entering from the opposite direction, the point C is written two.

Here, the attachment arrangement of the reference member (3) is determined, and the direction of movement of the moving vehicle (A) to the station (ST) is also detected. Therefore, based on the information read by the image sensor (Sa). Thus, it is possible to determine the displacement, and the operation of the manipulator (1) can be reliably executed from any direction.

In the above embodiment, the mark (3C) and (a) to (p) displayed on the reference member (3) are formed in a light-reflective manner, but the background of the reference member (3) is white. The marks (3C), (a) to (p) may be formed in black, or the marks (3C), (a) to (p) may be formed in a light projection type using a light emitting diode or the like. ) To (p) and the specific configuration of the reference member (3) can be variously changed.

Further, in the above-described embodiment, the case where the mobile vehicle (A) is configured to autonomously travel is exemplified. However, for example, the traveling vehicle (A) automatically travels using a traveling guide using a light reflecting tape, a magnetized guiding band, or the like. The specific configuration of each unit required for carrying out the present invention can be variously changed.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a mobile vehicle stop position detecting device according to the present invention. FIG. 1 is a plan view of the mobile vehicle stopped at a station, FIG. 2 is a front view thereof, and FIG. FIG. 4 is an explanatory diagram of a traveling route, FIG. 5 is an explanatory diagram of correction of a displacement of a moving vehicle, and FIGS. 6 (A) to (C) are plan views and partial plan views of reference members, respectively. Front view, FIGS. 7-9
FIGS. 10A to 10C are explanatory diagrams of misregistration detection, and FIGS. 10A to 10C are explanatory diagrams of misregistration detection according to another embodiment. FIGS.
FIGS. 12 (A) to 12 (E) are explanatory views of another embodiment of the reference member, and FIG. 13 is an explanatory view of another embodiment of the load transfer. (A)… Moving car, (ST)… Station, (Sa)…
... imaging means, (1) ... working device, (3) ... reference member, (100) ... shift amount determination means, (3C) ... element part,
(101)... Correction position determination means.

Claims (2)

(57) [Claims] A plurality of reference members (3) provided at a station (ST) in which a mobile vehicle (A) automatically travels and displaying reference position information in a plan view are distributed two-dimensionally. An element part (3C), each element part (3C) is configured to display information for specifying its own location with respect to the entirety of the reference member (3); Is configured to automatically move the imaging means (Sa) to the reading setting position of the reference member (3), and the imaging means (S) moved to the reading setting position
a) determining the amount of deviation of the moving vehicle (A) from the station (ST) from a setting appropriate stop state based on the display content of the element portion (3C) in the read information of (a). Correction position determining means (101) for determining a correction position at which the Sa) is to be moved and operated, wherein the working device (1) is configured to automatically move the imaging means (Sa) to the correction position; The shift amount determining means (100) for determining the shift amount is read information of the imaging means (Sa) moved to the correction position, or the information and the imaging means (Sa) moved to the read setting position. A) a moving vehicle stop position detecting device configured to determine the amount of deviation based on the read information in (2). 2. The stop position detecting device for a mobile vehicle according to claim 1, wherein the element portions (3C) are distributed and arranged at a central portion of the reference member (3) and an outer peripheral portion thereof. The correction position determining means (101) is provided with the reference member (3).
The reference member (3) among the element parts (3C) provided by
Stop position detecting device for a mobile vehicle configured to determine, as the correction position, two positions for imaging two element portions (3C) of the outer peripheral portion opposed to each other with the central portion therebetween. .