JPH04190407A - Stop position detection device for moving vehicle - Google Patents

Abstract

PURPOSE:To shorten the detection time by deciding a deviation quantity according to read information of an image pickup means which is moved to a correction position, or the information and read information of the image pickup means which is moved to a read setting position. CONSTITUTION:A manipulator 1 moves a two-dimensional image sensor Sa automatically to the read setting position corresponding to a reference member according to the command of a manipulator controller 12. A correction position discrimination means 101 which is constituted by utilizing a moving vehicle controller 10 and an image processing part 11 discriminates the correction position to which the sensor Sa should be moved according to the read information obtained by reading the reference member 3 by the sensor Sa. Then the sensor Sa is moved automatically to the correction position and display information of the member 3 is read. Then a deviation quantity discrimination means 100 discriminates the deviation quantity (X, Y, theta) according to the read information read by the sensor Sa at the correction position, or this information and the read information read by the sensor Sa at the read setting position corresponding to the member 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a reference member for displaying reference position information in a planar view at a station where a moving vehicle automatically travels, and a deviation amount determining means for determining the amount of deviation of the mobile vehicle from a properly set stop state with respect to the station based on information read by an imaging means for reading information displayed on the reference member. The present invention relates to a stop position detection device for a mobile vehicle, which is attached to the working device so that the imaging means is automatically moved to a set position for reading the reference member by the working device.

[Conventional technology]

Conventionally, in this type of stop position detection device for a moving vehicle, even if the moving vehicle stops in a state far away from the proper stopping state set for the station, the information displayed on the reference member can be reliably read, and the setting In order to satisfy the requirement of accurately detecting the amount of deviation from the stopped state, the device is configured to detect the amount of deviation while changing the imaging field of the imaging means from wide to narrow (Japanese Patent Application No. 1-83058).
(see issue).

To explain further, the imaging means is configured to be able to freely change its imaging field of view to wide or narrow, and calculates the amount of positional deviation of the reference member with respect to the center of the field of view based on the imaging information of the imaging means in a state where the imaging field of view is widened. a discriminating means for discriminating;
A correction means is provided for moving the imaging means in the horizontal direction so that the reference member is located closer to the center of the field of view based on the information of the determination means, and the deviation amount determination means is configured to adjust the position of the imaging means in a state where the imaging field of view is narrowed. The positional shift amount is determined based on the imaging information of the imaging means.

In other words, with this conventional means, even if the amount of deviation from the properly set stop state of the moving vehicle is large, the reference member can be reliably recognized if the imaging field is wide, and if the imaging field is narrow, the reference member can be recognized at a high In view of the fact that the amount of deviation can be detected with high accuracy by recognizing it with resolution, the amount of deviation is detected without changing the imaging field of the imaging means to be wide or narrow. Incidentally, by using an imaging means that can recognize the reference member with high resolution even in a wide imaging field, it is possible to omit changing the imaging field to a wide or narrow one.
Such imaging means are expensive and difficult to put into practical use.

[Invention or problem to be solved]

However, in the above-mentioned conventional technology, since the imaging field of view can be freely changed to wide or narrow, the structure of the imaging means becomes complicated and the weight becomes large. As the weight of the imaging means increases, the load on the working equipment increases, and even if the working equipment or the items handled are lightweight, the working equipment needs to be made durable. The drawback was that a large amount of driving energy was required to move the working equipment.

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

That is, a plurality of the reference members are provided at a predetermined distance apart, and the working device automatically moves the imaging means to a plurality of reading setting positions determined 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 alternative method calculates the amount of deviation of the vehicle body from the information read from multiple reference members separated by a distance, so it is useful, for example, when detecting the inclination of a moving vehicle that has stopped tilted relative to the properly set stopped state. By determining the inclination using the installation positional relationship of each reference member in a plan view, detection accuracy can be improved without recognizing each reference member with high resolution, and as a result, the imaging means In the above-mentioned conventional means that uses a heavy imaging means, it is necessary to make the work equipment durable for the imaging means, so that the amount of deviation can be detected with high accuracy while using a simple, lightweight and wide-field device. Disadvantages and the disadvantage that driving the working device requires a large amount of energy can be avoided.

However, since it takes time to move the imaging means to a plurality of reading setting positions determined corresponding to a plurality of reference members provided at a predetermined distance apart, it is difficult to detect quickly. The drawback was that it could not be realized. In other words, with this alternative means, in order to improve detection accuracy, it is necessary to place multiple reference members as far apart as possible, which increases the time required to move the imaging means, which makes detection difficult. It will be difficult to speed up the process.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to enable the use of a simple and lightweight imaging means without suppressing the deterioration of detection accuracy, and further, An object of the present invention is to provide a stop position detection device for a moving vehicle that can speed up detection by shortening detection time.

[Means to solve the problem]

In order to achieve this object, the first characteristic configuration of the stop position detection device for a moving vehicle according to the present invention is that a reference member is provided at a station where the moving vehicle automatically travels and displays reference position information in a plan view. , comprising a plurality of element parts distributed two-dimensionally, each element part being configured to display information for specifying its own placement location with respect to the entire reference member, the mobile vehicle The working device or the imaging means is configured to automatically move to a set position for reading the reference member, and based on the read information of the imaging means moved to the set position for reading, the movement of the moving vehicle with respect to the station is performed. Correction position determining means is provided for determining a correction position to which the imaging means should be moved in order to determine the amount of deviation from the properly set stop state, and the working device automatically moves the imaging means to the correction position. The deviation amount determining means for determining the deviation amount reads information read by the imaging device moved to the correction position, or that information and read information of the imaging device moved to the reading setting position. It is characterized in that it is configured to determine the amount of deviation based on.

Further, a second characteristic configuration specifies a preferable specific configuration for implementing the first characteristic configuration, wherein the correction position determining means selects one of the element parts included in the reference member. The present invention is characterized in that it is configured to determine two positions for imaging two element parts as the correction positions.

[For production]

According to the first characteristic configuration, when the mobile vehicle is stopped relative to the station, the working device to which the imaging means is attached is first activated, and the imaging means is read out corresponding to the reference member installed on the station side. The display information on the reference member is read by the imaging means. Next, based on this read information, a correction position to which the image pickup means should be moved is determined in order to determine the amount of deviation, and the image pickup means is automatically moved to this correction position to read the displayed information on the reference member. . Then, the amount of deviation is determined based on the read information at the correction position, or that information and the read information at the read setting position.

When detecting the amount of deviation in this way, a narrow field of view imaging means with high reading resolution is used, and even when the amount of deviation of the stop position of the moving vehicle is large, the information on the reference member can be reliably read. The reference member includes a plurality of element parts distributed two-dimensionally, and each element part is configured to display information for specifying its own placement location with respect to the entire reference member.

Therefore, by reading either the imaging means or the element portion of the reference member at the set position for reading, it is possible to determine the corrected position for determining positional deviation.

Since the reading operation at the correction position and the reading setting position is performed using a narrow-field imaging means,
The accuracy of detecting the amount of deviation can be increased, and since the correction position to which the imaging means is moved corresponds to the element part within the reference member, the distance the imaging means must be moved is short, and therefore This requires less time, and the detection operation can be processed quickly.

According to the second characteristic configuration, the imaging means is moved to the two correction positions determined by the correction position determination means, and the amount of deviation is determined based on the information read by the imaging means at each correction position. become. In this case, if the two correction positions are set for two element parts located far apart from each other among the plurality of element parts, the detection accuracy can be further improved by forward movement.

〔Effect of the invention〕

Therefore, according to the first characteristic configuration, the amount of deviation can be detected accurately and reliably even though a simple, lightweight, and narrow-field imaging device is used as the imaging device, so a heavy imaging device can be used. It is possible to avoid the disadvantages of the conventional means in which the working device must be made durable for the imaging means and the disadvantages of requiring a large amount of energy to drive the working device, and further speed up the detection operation can be realized. As a result, we have achieved a stop position detection device for a moving vehicle that is advantageous in terms of manufacturing and actual operation.

Furthermore, the second characteristic configuration makes it possible to further improve detection accuracy in addition to the effects of the first characteristic configuration.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

As shown in Figures 1 to 2 and 4, a work station is installed on the side of the travel path of a moving vehicle (A) equipped with a load transfer manipulator (1) as a work device. Several cargo transfer stations (ST) have been installed. Then, as the mobile vehicle (A) stops at the designated station (ST), the manipulator (
1), the system is configured to automatically transfer the load (N) between the station (ST) and the mobile vehicle (A).

Although details will not be given, the cargo (N) transferred to the mobile vehicle (A) at one station (ST) may be unloaded at another station (ST) or processed at the station (ST). Each time the train is completed, it is transferred to the moving vehicle (A) again and transported to the next station (ST).

However, the mobile vehicle (A) is configured to autonomously travel between stations (ST) without using a travel guide or the like. As will be described in detail later, the ibis station (S) stopped at the station (ST).
Based on the information on the amount of deviation in the width direction of the vehicle body (Y), the amount of deviation in the longitudinal direction of the vehicle body (X), and the inclination in the longitudinal direction of the vehicle body (θ) with respect to the reference position in the planar view with respect to T). Accordingly, the vehicle is configured to automatically correct the travel route to the next station (ST) (see FIG. 5).

In the figure, the stationary reference coordinate axes (hereinafter referred to as layout coordinate axes) of the travel control system for a moving vehicle to which the present invention is applied are the X" and Y" axes, and the reference coordinate axes fixed to the moving vehicle (A) are The longitudinal direction of the vehicle body is defined as the X' axis, and the width direction of the vehicle body is defined as the Y' axis.

Then, the center (AC) of the moving vehicle (A) is set as the origin of the X', Y' coordinate axes, and the moving vehicle (A) further moves to the station (
Settings for ST) When stopping in the proper stopping state,
The center (AC) or the reference position on the layout coordinate axis (L
C), and the X" axis and the X° axis are parallel, and the Y
The ``axis and the Y'' axis are parallel.

To further explain the travel route between the stations (ST), as shown in Fig. 4, the longitudinal direction of the moving vehicle (A) is set as the X'' axis, and the lateral direction of the vehicle body is set as the Y'' axis. It is. And two stations (S
The distance (β,
) and the distance (12) in the Y'' axis direction, the information of the regular route (LO) on which the mobile vehicle (A) autonomously travels is set and stored in advance.However, the mobile vehicle (
A) is assumed to be run from one station (STY) to the other station (ST, ).

The regular route (L,) includes the two stations (L,).
Distance information for each straight line section (T, ), (T2), (T3) divided into a plurality of straight lines connecting ST, ), (ST2), and each straight line section (T, ), (T2) , (
Turning radius (R,), (R2) and turning angle (θ1), (θ2) for changing direction at the connection point of T3)
The distance information and the turning angle information are mapped and stored in advance as traveling side image information for the moving vehicle (A).

That is, the moving vehicle (A) moves from one station (S'I'2) to the other station (STI) based on the stored traveling side picture information in each of the straight sections (
TI), (T2), and (T3) in that order, the train autonomously travels while turning at a set radius and angle at the connection point of each section, and automatically moves to the next station (ST,). This makes it possible to stop it.

In FIG. 4, (r,), (r2) are distances between the stations (ST,), (ST2) and the regular route (L,) in the vehicle width direction.

As shown in FIGS. 1 and 2, the station (S
T), when the moving vehicle (A) stops at the designated station (ST), the station (ST)
), the amount of deviation of the moving vehicle (A) from the properly set stop state is detected, and the operating amount of the manipulator (1) is automatically corrected, or the moving vehicle (A) is moved to the next station (ST). A reference member (3) is provided to display reference position information with respect to the station (ST) in order to automatically correct the traveling route when the vehicle is traveling toward the station (ST).

As shown in FIGS. 6(A) and 6(B), the reference member (3) has an element section that displays information for specifying its own placement location with respect to the entire reference member (3). The element mark (3C) at Dimensionally distributed. In the figure, the Y axis is the longitudinal direction of the vehicle body, the Y axis is the lateral direction of the vehicle body, and the center point (0') is the origin of the X and Y coordinates. Furthermore, each element mark (3C) is arranged on a straight line connecting three circles with different diameters (large circle, middle circle, small circle) or their centers of gravity, and at a predetermined distance apart in order of size, Further, the center point (0') is located at a predetermined distance on the smaller diameter side on the extension of this straight line.

Further, the moving vehicle (A
) and which station (ST) is stopped, address information assigned in advance is displayed at the same time.

As shown in FIG. 6(C), the reference member (3) is formed by forming a sheet-like prism-type light reflector (3a) of a set size to totally reflect incident light in the direction of incidence. A resin flat plate (3b) painted matte black is attached to the surface. In addition, FIG. 6(C) shows Y in FIG. 6(A).
A cross section along the axis is shown.

The black flat plate (3b) has the station (ST
), four reference position marks (a) to (d) displaying reference position information for the reference position information, and a plurality of address marks (e) to (e) displaying the address information in the form of a binary code.
A plurality of through holes with the same diameter are arranged in a predetermined manner to form three types of marks: address marks (e) to (parity marks (m) to (p) for I). In other words, the reference members (3
) are formed so that only the portions where the marks (3C), (a) to (p) are formed are reflected and appear brighter than the surrounding areas.

Here, the intersection of line segments diagonally connecting the centroid positions of the four reference position marks (a) to (d) is the reference member (3).
) to coincide with the center point (0゛).

Also, in order to make it easier to recognize which mark it is,
The four reference position marks (a) to (d) are located at each vertex of a square centered on the center point (0') of the reference member (3), and )~<i
> are divided into upper and lower parts in the X-axis direction along the longitudinal direction of the vehicle, and lined up in the Y-axis direction along the vehicle width direction, inside the reference position marks (a) to (d). and the parity mark (m
) to (p) are arranged horizontally in the X-axis direction of the address marks (e) to (β), respectively.

Incidentally, the reading of each mark (3c), (a) to (p) and the determination of the read information will be described later.

As shown in FIGS. 1 and 2, the mobile vehicle (A) is
A pair of left and right propulsion wheels (6) are provided at approximately the center in the longitudinal direction of the vehicle body, and a pair of propulsion wheels (6) are provided at each of the front and rear ends of the vehicle body. It includes a pair of left and right idle wheels (7). In other words,
The moving vehicle (A) is constructed so that it can change direction on the spot.

Further, the moving vehicle (A) is equipped with an optical fiber type gyro device (Sb), and detects a deviation in the traveling direction from the normal route (L,) based on the information of the gyro device (Sb). The pair of electric motors (5) are arranged so as to differentiate the rotational speeds of the pair of left and right propulsion wheels (6).
The vehicle is designed to be steered by changing gears.

In FIG. 1, (Sc) indicates the pair of left and right propulsion wheels (6
) is a ground-contact wheel-type travel distance detection sensor installed at the center of rotation of the vehicle.

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

In Fig. 3, (11) is an image sensor (Sa
), an image processing unit (12) processes the image information of the reference member (3) and transmits the information of the reference member (3) to the mobile vehicle controller (10); (1) is a manipulator controller that controls the operation; (13) is a travel controller that controls the operation of the travel motor (5) that drives the left and right propulsion wheels (6); (14) is the travel controller Based on the command (13), the traveling motor (5
), and (15) is a setting device for manually setting destination information for the mobile vehicle (A) and manually setting various information for recovery in case of emergency stop, etc. .

As shown in FIGS. 1 and 2, the manipulator (1) is constructed in a so-called multi-joint type, and has a load carrying tool (2) at its tip.
A two-dimensional image sensor (Sa) is attached as an imaging means for reading display information on the reference member (3). Although not described in detail, the manipulator (1) determines the operating amount of the electric motor provided at each joint based on information from an encoder that detects the operating amount and various control information stored in advance. The cargo transfer work will be carried out under controlled conditions.

Next, a description will be given of stop position detection for detecting the amount of deviation (X, Y, θ) of the moving vehicle (A) from the properly set stopped state when the moving vehicle (A) is stopped at the station (ST).

The manipulator (1), based on a command from the manipulator controller (12), places a two-dimensional image sensor (Sa
) is automatically moved, and the correction position is configured using the mobile vehicle controller (10) and the image processing unit (11) based on the read information read from the image sensor (Sa) or the reference member (3). A determining means (201) determines a correction position at which the two-dimensional image sensor (Sa) should be moved, and then moves the two-dimensional image sensor (Sa) to this correction position.
Sa) is automatically moved to read the displayed information on the reference member (3).

Then, the moving vehicle controller (10) and the image processing section (
II) Displacement amount determining means (100) configured using
is the read information read by the two-dimensional image sensor (Sa) at the correction position, or the read information read by the two-dimensional image sensor (Sa) at the reading setting position corresponding to this information and the reference member (3). Based on
The amount of deviation (X, Y.

θ). 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 each of the coordinate axes x and y on the image of the two-dimensional image sensor (Sa) are configured to be parallel to the coordinate axes X', Y'' of the moving vehicle (A).

The operation procedure for positional deviation detection will be explained with reference to FIGS.
Sa) is moved to the reading setting position corresponding to the reference member (3).

Normally, there are errors caused by autonomous running, so the X-Y axes of the reference member (3) and the x-y axes of the imaging field of view of the image sensor (Sa) do not match, and the origin of the X-Y axes ( O") and the origin (G) of the x-y axes are also shifted (see Figure 7). In the illustrated state, the image sensor (Sa) is an imaging means with a narrow field of view, and the positional shift is large. , the reference member (3
) center position (0") is not within the imaging field of view,
A state in which one of the element marks (3C) is captured is shown.

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. is output as coordinate detection information for the entire reference member (3).

In FIG. 7, of the three circles constituting 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 mentioned above, the reference member (
3) has the center (0゛), and let Q be the intersection of the line segments that are parallel to the x-y axis and pass through point ○' and point P, then there are 3 points ○', P,
Q makes a right triangle.

Also, let the angle between the line segment 0'P and the y-axis be θ, and the coordinate values of the centroid positions P and R of the circle on the x-y coordinate axes are (
x+, y+), (X2. Y2).

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

Coordinate values (xo, yo) of the center (0°) of the reference member (3) on the screen coordinate axis x-y axis of the image sensor (Sa)
) can be calculated using the following formula.

XO-○'Qx, =O'Psinθ, +x1yo
=QP+y+ =0'Pcosθ, +y.

Here, since the line segment 0'P is determined in advance due to the configuration of the reference member (3), the coordinate values (Xo, yo) are determined as a specific amount of detected information.

Next, the coordinate value (x
o, y o), and two element marks (3CL) placed equidistantly in the left and right direction on the X axis corresponding to the longitudinal direction of the vehicle from the center (0°),
(3CR) as the correction position, and in order to image these correction positions and the marks (a) to (p), the center (0') of the reference member (3) and the center (G) of the imaging field of view are determined. A correction amount for operating the manipulator (1) to the overlapping position is determined.

Then, by operating the manipulator (1) by the distance corresponding to the correction amount, the image sensor (Sa) is moved, and the element mark (3CL) - marks (a) to (p
)→Element mark (3CR) is moved in parallel on the imaging field of view X-axis and captured. The screen where the element mark (3CL) is imaged by the image sensor (Sa) is the imaging field of view (SL), and the screen where the element mark (3CR) is imaged is the imaging field of view (S,).
(See Figure 8). Note that the order of imaging the imaging field of view (SL) and the imaging field of view (9) can be arbitrary.

FIG. 10(A) shows images of marks (a) to (p).

Here, a method for determining the deviation angle of the moving vehicle (A) from the station (ST) in the longitudinal direction of the vehicle body will be explained with reference to FIG. Each imaging field (SL), (S,)+:
Hey, element? - To detect the positions of (3CL) and (3CR), for example, detect the center of gravity of the largest circle, and calculate its coordinate values (X3. Y3).

(X4. y4). Further, the angle between the straight line (X-axis) connecting the element marks (3CL) and (3CR) and the screen coordinate X-axis is θ. Here, element mark (3CL), (
Since the distance (L) between the reference members (3CR) is determined in advance due to the configuration of the reference member (3), the above-mentioned inclination θ can be obtained as shown in the equation below.

On the other hand, the X-axis of the reference member (3) corresponding to the longitudinal direction of the vehicle body is installed so as to be parallel to the layout coordinate axis X" axis of the station (ST) corresponding to the longitudinal direction of the vehicle body, and Since the X axis corresponding to the direction is configured to be parallel to the X' axis corresponding to the longitudinal direction of the vehicle body of the coordinate axis fixed on the vehicle body (A), the X axis corresponding to the vehicle body (A) with respect to the station (ST) is ) is given by θ.

Furthermore, the coordinate values of the center (AC) of the mobile vehicle (A) are also determined by the fact that the image sensor (Sa) is moved by a predetermined amount of operation to the set position for reading as described above. The center position of the imaging screen and the center (AC) of the moving vehicle (A)
), the coordinate values (xo, yo) corresponding to the distance between the center (0') of the reference member (3) and the center position of the imaging screen are used as correction amounts to perform coordinate transformation. Finally, the reference stopping position (LC) on the layout coordinate axes and the center position of the moving vehicle (A) (
It is possible to find the amount of deviation (X, Y) corresponding to the difference in coordinates from AC).

Therefore, the value of the deviation amount (X, Y) and the slope (θ)
By correcting the amount of movement of each joint that is set and stored in advance based on the value of This allows the load carrying device (2) of the manipulator (1) to properly grip the load (N) that is already in a small position with respect to the reference member (3).

Further, the address marks (e) to (12) and the parity marks (m) to (p) to be read on the screen that images the marks (a) to (p) are stored in advance according to their sizes. The reference position marks (a) to (d)
), the address mark (e)
~(β) and the presence or absence of the parity marks (m) to (p), and based on the combination of the presence/absence of the marks, the moving vehicle (A) or the station (ST) at which it is currently stopped is determined. The address will be determined.

When the load transfer operation is completed, the next station (ST) stored in advance or instructed by the central control unit (8) via the communication devices (9a) and (9b) is selected. The next station ( The vehicle will correct the traveling direction for traveling to ST) and start automatic traveling.

To explain the correction of the running direction, as shown in FIG.
Assuming that the vehicle is stopped with a positional shift and inclination occurring in the direction approaching the
Based on the value of Y) and the value of the inclination (θ), the vehicle is oriented in the direction of the set and memorized regular route (L,) within a range that does not collide with the moving vehicle (A) or the station (ST). The maximum changeable angle (θS) and the normal route (
The travel distance (Ts) to the contact point (0) with L, ) is determined, the gyro device (Sb) is reset, and information on the detected travel direction is initialized.

Next, based on the information of the gyro device (Sb), the left and right propulsion wheels (6) are reversed to make a spin turn on the spot, and the tilt (θ) and the maximum angle at which the direction can be changed ( After changing the direction of the normal route (L,) by the angle obtained by adding θS), the calculated travel distance (L,) is calculated at low speed based on the information from the travel distance detection sensor (Sc). Ts) is driven straight and stopped at the contact point (0) with the regular route (L, ). After that, the maximum angle (θS) is changed to the station side with a spin turn, and the vehicle travels at the set speed so as to autonomously travel along the regular route (LO) and travel to the next station (ST). It will get started.

After starting automatic travel along the regular route (L,), as described above, the left and right propulsion wheels (6) are operated with a rotational speed difference based on the information from the gyro device (Sb). direction, and the distance detection sensor (Sc)
Based on the information, the position of the mobile vehicle (A) on the regular Lo is determined, and the vehicle is automatically stopped when it reaches the next station (ST).

[Another example]

In the above embodiment, the correction position for determining the positional deviation is determined based on information obtained by reading the reference member (3) by the image sensor (Sa) at the set reading position corresponding to the reference member (3). After that, as the next operation, operate the manipulator (1) to the above correction position and a position where the center (0) of the reference member (3) and the center (G) of the imaging field of view overlap, and move the image sensor (Sa). Although the amount of deviation is detected, it is possible to perform such an operation in a manner different from that described above, and modifications of these operations will be described below.

Another operation example (1) (see Figures 10(A) and 10(B)) In this embodiment, first, the screen center position of the image sensor (Sa) given as information from the correction position determining means (101) is and the coordinate amount (XO) corresponding to the distance from the center position (0') of the reference member (3).

yo) 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 match due to errors in screen measurement by the image sensor (Sa), errors in the operation of the manipulator (1), etc. (See Figure 10(B)).

Here, the coordinate value on the screen coordinate X-y axis of the intersection point of the line segment diagonally connecting the centroid positions of the four reference position marks (a) to (d) captured by the image sensor (Sa) By detecting (ΔX, Δy) and adding it to (Xo, yo) obtained from the screen measurement of the element mark (3C), the amount of deviation (
This can be defined as (X+o, y+o)) and the detection accuracy of the deviation amount (x, y) of the stop position of the moving vehicle (A) determined based on this can be improved. Note that in FIG. 10(B), address marks (e) to (p) are omitted for the sake of explanation. Writing it as a formula, it can be expressed as follows.

X1 o - X0 + Δ The reference position mark (
From the positional relationships with respect to a) to (d), the address marks (e) to (A) and the parity marks (m) to
(p) is determined, and based on the previous year's combination of the marks, the moving vehicle (A) or the address of the currently stopped station (ST) is determined.

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

Here, if θ=0°, the above deviation amount (X+o, Y+o)
The relationship between and (X, Y) is as follows.

X + o = X + Y + o = Y-specific operation example (2) (see Figures 10 (A), (B), and (C))
First, operate the manipulator (1) by the coordinate amount (Xo, yo) by the same operation as the above-mentioned another operation example (1),
Move the image sensor (Sa) to the center position of the reference member (3). The screen here becomes the imaging field of view indicated by 82 in Figure 1O(C). Note that Sl is the imaging field of view before the movement. In the S2 field of view, the amount of deviation (ΔX, Δy+) between the intersection of line segments diagonally connecting the centroid positions of the four reference position marks (a) to (d) and the screen coordinate center, and the amount of deviation of the reference member (3) The deviation angle between the coordinate axes and the screen coordinate axes is determined by setting θ=03. It is shown by the following formula.

Δ)'+= =□ X−Xd let

Then, the imaging field of view becomes 83 in FIG. 10(C).

Normally, even at this stage, the center of the reference member (3) and the center of the screen are misaligned due to the measurement and operation errors mentioned above.
The coordinate axes are also not parallel.

In the state of S3, the amount of deviation (ΔX2Δyz),
The amount of deviation (Δθ2) is determined.

By adding the detected values obtained in the process of correcting the amount of positional deviation as described above, the amount of deviation from the center of the reference member (3) to the center of the screen coordinates (this is (X 20.
Therefore, the stop position deviation amount (X, Y) of the vehicle body (A) with respect to the station (ST), which is determined based on this, can be detected with high accuracy.

x2゜=XO+∆x1+∆x2 y2o=yo+∆y1+∆y2 In addition, the above-mentioned another operation example (
It can be implemented in the same way as 1).

Next, in order to detect the angular deviation, as described above, the element marks (3CL) and (3CR) corresponding to the Move the image sensor (Sa) to the correction position, and use the information read there to determine the slip angle θ4 between the X coordinate axis of the reference member (3) and the screen coordinate X axis (see Figure 9). Reread θ in the equation as 04. In the end, the deviation angle of the vehicle body (A) with respect to the station (ST) is determined by θ=03+04.

Here, since the initial angular deviation θ3 is corrected by rotating the image sensor (Sa) as described above, θ4 has a value close to 0. Therefore, even when the angular shift amount is processed using screen coordinate values, it can be performed in an imaging area with little screen distortion, so that highly accurate results can be obtained.

Furthermore, even if the deviation by one angle is abnormally large, if the image sensor (Sa) is moved to the corrected position for detecting the positional deviation, the detection operation can be performed without going out of the imaging field of view.

Further, if θ=0°, the relationship between the amount of deviation (X20. Y2O) and (X, Y) is as follows.

X20=X+'! 2a=Y Another operation example (3) This embodiment uses an image sensor (S
Is it the same until moving a) from the set position for reading to the mark center position?After that, by detecting the reference position marks (a) to (d) at the center position, the amount of positional deviation, the deviation This is used to determine the angle (Fig. 10(A),
(See (B)).

This simple method is possible because a high-resolution, narrow-field image sensor (Sa) is used. Further, it is also possible to read address marks (e) to (p) in the same way.

Further, in the above embodiment, as shown in FIG.
) is shown as an example of a configuration consisting of one type of element mark (3C), but the element mark (3C) may display information that allows identification of its placement location with respect to the entire reference member (3). Below, another reference member (
A configuration example of 3) will be explained (see FIGS. 11(A) to 12(D) and 12(A) to 12(E)).

What is shown in FIGS. 11A to 11D are modified examples of element marks consisting of a combination of circles, and there are three types of element marks. For example, in the case shown in FIG. 11(B), the centers of three small circles are arranged on a straight line with a predetermined distance apart, and this straight line is parallel to the X-axis and perpendicular to this straight line. A large circle and a reference member (
3) Located in the center of The center of this reference member (3) is the origin of the XY coordinates, and they are placed at equal distances on both sides of the reference member (3) in the Y-axis direction. In Fig. 11(C), three small circles and one large circle are arranged at each vertex of a square, and a reference member ( 3), and the angle between this straight line and the XY coordinate axes is 45°. Four element marks in FIG. 11C are arranged at each vertex of a square whose sides are parallel to the XY axes and whose centers are at the origin of the XY coordinates. What is shown in FIG. 11(D) is a large circle, a middle circle, and a small circle, each of which is arranged in the order of size on a straight line parallel to the X-axis, and is an extension of the small inner side on this straight line. The origin of the XY axes, that is, the center of the reference member (3), is located at a predetermined distance on the line, and two marks are placed at equal distances on the left and right on the X axis. Note that the reference position marks (a) to (p) are arranged at the center of the mark.

Next, image processing for determining the correction position from the read information of the marks shown in FIGS. 11(B) to 11(D) will be described. In the case shown in FIG. 11(B), the diameters of four circles are identified, the center of gravity of each circle is detected, and the center direction and center position of the reference member (3) are determined.

In the case shown in FIG. 11C, the diameters of four circles are identified and the center of gravity of each circle is detected, and the center direction and center position of the reference member (3) are determined. In the case of FIG. 11(D), the winter diameter and center of gravity position are detected, and the center direction and center position of the reference member (3) are determined in the direction of the small circle.

Then, in order to detect the positional deviation 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).

Further, at the reading setting position, an image sensor (Sa
), when there are two or more types of element marks in the imaging field of view of the reference member (3), it is possible to prioritize the mark discrimination, for example, as shown in FIGS. 11(B) and (C).
, (D), the accuracy of position detection can be improved by using element marks closer to the center of the reference member (3).

Further, another example of the configuration of the reference member (3) is shown in FIG.
) to (E). This example is constructed by combining a rectangle and some small circles. Figure 12(B)
is a parallelogram consisting of long and short diagonals, its center of gravity is located at the center of the reference member (3), the direction of the long diagonal is the X axis, and the direction of the short diagonal is the Y axis. ing.

In FIG. 12C, the length from the center of gravity of the rectangle to each corner is longer by one, and the lengths to the other three corners are the same. A straight line extending from the center of gravity to the corner or toward the long corner is the Y-axis, and the center of the reference member (3) is located on the extension of this straight line. The marks are located at two equidistant positions above and below the Y axis.

What is shown in Fig. 12(D) is a combination of the rectangle and small circle in Fig. 12(C), and the small circle is on the straight line connecting the center of gravity of the rectangle and the corner with the long length to the corner. , and the longer corner is configured to be on the opposite side.

Also, the straight line connecting the center of gravity of the rectangle and the small circle is the mark coordinate axis
, forms an angle of 45° with respect to the Y axis, and the origin of the XY coordinates, that is, the center of the reference member (3), is on the extension of this straight line on the opposite side to the small circle.

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

Two marks are located at equal distances from each other on the left and right sides of the X-axis.

Next, image processing for determining the positional deviation and corrected position from the read information of the marks shown in FIGS. 12(B) to 12(E) will be described. In the case shown in FIG. 12(B), the center position of the rectangle can be detected and the center position of the reference member (3) can be determined. Furthermore, the direction of the diagonal of the quadrilateral can be detected and the angle of deviation can be determined. In the case of Fig. 12(C), by identifying the center of gravity position of the rectangle and the length and direction of the diagonal,
Find the center direction and position of the reference member (3). Figure 12 (D
) detects the position of the center of gravity of the rectangle, the straight line and direction connecting this and the center of gravity of the small circle, and determines the direction and position of the center of the reference member (3). In the case shown in FIG. 12(E), the center of gravity of a rectangle and the center of gravity of a small circle are detected, and the direction and position of the center of the reference member (3) are determined.

Next, in order to detect the angle of positional deviation from the read information at the correction position, for example, at the correction position, by detecting the center of gravity of the small circle in the mark in FIG. Perform this method (see Figure 9).
.

Further, at the reading setting position, an image sensor (Sa
) in the field of view in which the reference member (3) is imaged.
When there are element marks of more than one type, it is possible to prioritize the mark discrimination. For example, Fig. 12(B), (C
), (D), (E) in the order of reference member (3)
The accuracy of position detection can be increased by using element marks closer to the center of the element.

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

In the example just described, the load (N) was transferred from only one direction with respect to the station, as illustrated in FIGS. 1 and 4. However, the reference member (3) configured according to the present invention is configured in such a way that even when the reference member (3) is partially grasped, its location relative to the whole can be specified. (N) Transfer is possible (
(See Figure 13).

In the figure, A I+ A2. A 3 moving vehicles (A
), but this is one mobile vehicle (A)
The figure shows a load (N) transferred from three directions.

Here, C indicates that the manipulator (1) is installed in the center, and (16)
) is a conveyor for transporting load (N), and (17) is a stocker.

Note that A2 assumes that the moving vehicle (A) enters from the opposite direction, so 0 or 2 points are written.

Here, the placement of the reference member (3) has been determined, and the direction of approach of the moving vehicle (A) to the station (ST) has also been detected, so based on the information read by the image sensor (Sa), , displacement can be detected, and the manipulator (1) can be operated reliably from any direction.

In addition, in the above embodiment, the case where the marks (3C), (a) to (p) displayed on the reference member (3) are formed in a light reflective manner is exemplified, but the background of the reference member (3) is white. The marks (3C), (a) to (p) may be formed in black, or may be formed in a light projection type using light emitting diodes, etc., and the marks (3C), (a) may be formed in black. ) to (p) and the specific configuration of the reference member (3) can be changed in various ways.

Further, in the above embodiment, the case where the mobile vehicle (A) is configured to run autonomously has been exemplified. (The specific configuration of each part necessary for carrying out the present invention can be modified 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 drawings]

The drawings show an embodiment of the stop position detection device for a mobile vehicle according to the present invention, in which FIG. 1 is a plan view of the vehicle stopped at a station, FIG. 2 is a front view of the same, and FIG. 3 is a control system. A block diagram of the configuration, FIG. 4 is an explanatory diagram of the traveling route, FIG. 5 is an explanatory diagram of correcting the displacement of the moving vehicle, and FIGS. 6(A) to 6(C) are a plan view and a partial plan view of the reference member, respectively. Front view, Figures 7 to 9
The figure is an explanatory diagram of positional deviation detection, 10th (A) to (C) are explanatory diagrams of positional deviation detection of another embodiment, and 11th (A) to (D
) and 12(A) to 12(E) are explanatory diagrams of another embodiment of the reference member, and FIG. 13 is an explanatory diagram of another embodiment of load transfer. (A)...Moving vehicle, (ST)...Station, (Sa)...Imaging means, (1)...
...Working device, (3) ...Reference member, (10
0)...Displacement amount determination means, (3C)...-
Element part, (101)...Correction position determination means.

Claims (1)

[Claims] 1. Station (ST) where the mobile vehicle (A) automatically travels
A reference member (3) that is provided in and displays reference position information in a plan view includes a plurality of two-dimensionally distributed element parts (3C), each of which is arranged in the same manner as described above. The working device (1) of the moving vehicle (A) is configured to display information for specifying its own placement location with respect to the entire reference member (3),
is configured to automatically move the reference member (3) to a set position for reading, and based on the read information of the imaging means (Sa) moved to the set position for reading, the position of the reference member (3) for the station (ST) is The imaging means (
A correction position determining means (101) is provided for determining a correction position at which the movement operation of the image pickup means (Sa) should be performed, and the working device (1) moves the imaging means (101) to the correction position.
The displacement amount determining means (100) is configured to automatically move the image pickup means (Sa), and the displacement amount determination means (100) for determining the displacement amount reads the reading information of the imaging means (Sa) that has been moved to the correction position, or the information and the reading information. A stop position detection device for a mobile vehicle configured to determine a shift amount based on information read by the imaging means (Sa) moved to a set position. 2. The stop position detection device for a moving vehicle according to claim 1, wherein the corrected position determining means (101) is configured to detect the reference member (3).
) of the element parts (3C) included in two element parts (
3C) A stop position detection device for a mobile vehicle configured to determine two positions for imaging as the correction positions.