JP3481363B2 - Cargo handling vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cargo handling vehicle, and more particularly to a cargo handling vehicle for carrying a load mounted on a gate type pallet.

[0002]

2. Description of the Related Art FIG. 10 is a schematic diagram showing a schematic configuration of an example of a conventional cargo handling vehicle 1 '. In the figure, a loading platform 1c which is moved up and down by a hydraulic cylinder 1d is attached to a vehicle body 1
It shows a state in which a heavy cargo loaded on the gate type pallet 2 is transported by the cargo handling vehicle 1'equipped in a. First, the gate type pallet 2 is placed on the loading platform 1c. in this case,
The vehicle body 1a is dipped under the pallet in a state where the loading platform is lowered, and then the loading platform is raised to lift the pallet.
Then, after carrying the pallet to a predetermined position, the loading platform 1c
Take down the gate type pallet 2 from. In this case, the loading platform is lowered again to lower the pallet, and the vehicle body 1a is withdrawn from under the pallet.

[0003]

In the conventional cargo handling vehicle 1'as described above, the width Wp of the lower portion of the gate type pallet 2 is reduced.
And the width Wv of the vehicle body 1a are small, the allowable values of the inclination of the vehicle body with respect to the pallet center axis and the lateral displacement of the vehicle body in the pallet lateral width direction when viewed under the pallet are extremely small. . For this reason, when the vehicle body goes under the pallet 2, it is necessary to correct the inclination and lateral deviation of the vehicle body at a position in front of the pallet, and then to move the vehicle body under the pallet while maintaining a gap between the vehicle body and the pallet. Conventionally, such a work is performed by a driver in the driver's seat 1b1 by visual inspection or intuition.
It required skill to operate the cargo handling vehicle 1 '. In addition, the driver may have to get on the driver's seat 1b2 on the opposite side toward the pallet and sneak backwards, but at this time, instructions from an assistant outside the vehicle are required, which requires manpower. In order to solve the problems in the related art, the present invention provides an improved cargo handling vehicle that can be easily driven without depending on the driver's intuition or an assistant. The purpose is.

[0004]

In order to achieve the above-mentioned object, the present invention makes the car body go under a gate type pallet consisting of a loading table and legs, and uses the lifting mechanism provided in the car body. In a cargo handling vehicle that lifts and transports a gate-type pallet, an irradiation means for irradiating the leg of the gate-type pallet with slit light diverging in the same plane and an imaging axis intersect the plane. And image capturing means for capturing an image of the portal type pallet irradiated with the slit light, and image analysis of the irradiation line on the imaged portal type pallet to obtain the position of each point of the portal type pallet. Means and the gate-type pattern obtained by the image analysis means.
And a calculating means for calculating the vehicle body relative position and orientation with respect to the gate-shaped pallet based on the position of each point let the upper
The image analysis means is such that the vehicle body is below the gate pallet.
Before diving into the
On the other hand, while the car body is traveling below the gate pallet,
Of an arbitrary point on the optical cutting line imaged by the image pickup means
It is configured as a cargo handling vehicle characterized in that the position of a set is obtained. Further, the cargo handling vehicle is provided with a display means for displaying the relative position and orientation of the vehicle body with respect to the gate type pallet.

According to the present invention, when the car body is made to dive under a gate type pallet composed of a loading table and legs, and when the gate type pallet is lifted and conveyed by an elevating mechanism provided in the car body, Slit light that diverges in the same plane toward the legs of the portal pallet is emitted by the irradiation means. An image of the portal pallet irradiated with the slit light is imaged by the image pickup means arranged so that the image pickup axis intersects the plane. Each image of the portal type pallet is analyzed by the image analysis of the irradiation line on the portal type pallet.
The position of the point is obtained by the image analysis means. The relative position and orientation of the vehicle body with respect to the gate type pallet is calculated by the calculation means based on the positions of the points . At this time, the above image
In the image analysis means, the car body is hidden below the gate pallet.
Before inserting, the position of the feature point of the leg is calculated
So, while the car body is traveling below the gate pallet,
A set of arbitrary points on the optical cutting line imaged by the image pickup means
Find the position of. As a result, the car body is
Before diving under the car and the car body is
In both cases, the tilt and lateral deviation of the car body can be calculated accurately, and the risk of collision between the gate pallet and the car body is reduced. Further, if the relative position / orientation of the vehicle body with respect to the gate type pallet is displayed by the display means, the driver dives under the same pallet while checking the relative position / orientation of the vehicle body with respect to the gate type pallet.
You can easily exit. As a result, the cargo handling vehicle can be easily driven without depending on the driver's intuition or an assistant.

[0006]

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
The following embodiments and examples are examples of embodying the present invention and are not of the nature to limit the technical scope of the present invention. FIG. 1 is a block diagram showing a schematic configuration of a cargo handling vehicle 1 according to the embodiments and examples of the present invention,
2 is a plan view, a front view and a side view of the cargo handling vehicle 1, FIG.
Is an explanatory view showing the procedure of diving into the gate type pallet, Fig. 4
Is an explanatory diagram showing how to determine the inclination and lateral deviation of the vehicle body, FIG. 5 is an explanatory diagram showing the image processing result of the imaged optical cutting line, and FIG. 6 is an explanatory diagram of the image processing during diving into the portal pallet. 7
FIG. 8 is an explanatory diagram showing how the cargo handling vehicle of Modification 1 dives into the portal pallet, FIG. 8 is an explanatory diagram showing how the cargo handling vehicle of Modification 2 dives into the portal pallet, and FIG. FIG. 8 is an explanatory diagram showing how to determine the inclination and lateral deviation of the vehicle body of Example 2; The same reference numerals are used for the elements common to the schematic diagram showing the schematic configuration of the conventional cargo handling vehicle 1'shown in FIG.

As shown in FIG. 1, in a cargo handling vehicle 1 according to the embodiment and examples of the present invention, a car body 1a is slid under a gate type pallet 2 composed of a loading table and legs. This is the same as the conventional example in that the gate type pallet 2 is lifted and conveyed by the elevating mechanism provided in the vehicle body. However,
In the present embodiment and examples, the laser light source 3 (corresponding to the irradiation means) that irradiates the slit light diverging in the same plane toward the legs of the gate type pallet 2 and the imaging axis with respect to the plane. A CCD camera 4 (corresponding to an image pickup means) which is arranged so as to intersect and which images the portal pallet 2 irradiated with the slit light, and an image analysis of an irradiation line of the gate pallet 2 which is imaged, the gate is obtained. An image processor 5 (corresponding to image analysis means) for obtaining the positions of the characteristic points of the mold palette;
It is different from the conventional example in that it is provided with a CPU 6 (corresponding to a calculation means) which calculates the relative position and orientation of the vehicle body 1a with respect to the gate type pallet 2 based on the positions of the characteristic points. Further, CRT displays 7a and 7b (corresponding to display means) for displaying the relative position and orientation of the vehicle body 1a with respect to the gate type pallet 2 may be provided, which is also different from the conventional example.

The structure of the cargo handling vehicle 1 will be further clarified below with reference to FIG. As shown in FIG. 2, a vehicle body 1a equipped with a luggage carrier 1c on the upper part can be moved up and down by a hydraulic cylinder 1d (corresponding to an elevating mechanism). Car body 1a
A laser light source 3 for irradiating slit light is installed in the front part of the vehicle, and projects the slit light horizontally toward the front of the vehicle body 1a. A CCD camera 4 is attached below the laser light source 3, and its imaging axis is directed obliquely upward and forward of the vehicle body 1a, so that it intersects the plane of the slit light. In the vehicle body 1a, the image processor 5 and C shown in FIG.
The PU 6 is installed, and the image captured by the CCD camera 4 is analyzed here, and the relative position and orientation of the vehicle body 1 a with respect to the gate type pallet 2 is calculated. CPUs are provided in the driver's seats 1b1 and 1b2 provided in front of and behind the vehicle body 1a, respectively.
CRT display 7a for displaying the calculation result by 6.
7b is installed. Next, how the cargo handling vehicle 1 dives into the gate type pallet 2 will be described with reference to FIG.

First, before diving into the gate type pallet 2, FIG.
As shown in (a), slit light is emitted from the laser light source 3 toward the legs of the portal pallet 2. At this time, the left and right legs 2b1 and 2b2 of the gate type pallet 2 are displayed on the CCD camera 4.
An image of the slit light that hits is captured. This image is input to the image processor 5, and a characteristic point of the gate type pallet 2, for example, a point P on the outer corner of the legs 2b1 and 2b2 of the pallet.
1, P2 on the image corresponding to P2 (see FIG. 4), Pg1, P
g2 (see FIG. 5) is extracted, and the relative position of the points P1 and P2 with respect to the vehicle body 1a is calculated by the CPU 6 using the positional relationship between the laser light source 3 and the CCD camera 4. The relative position and orientation of the vehicle body 1a with respect to the gate type pallet 2 at this time is expressed as follows.

[Equation 1] Here, as shown in FIG. 4, θy is an angle (tilt) formed between the virtual center line Lp of the portal pallet 2 and the center line Lv of the vehicle body 1a, and d is the origin Ov on the center line Lv and the center. A distance (horizontal deviation) D from the line Lp is a distance between an intersection Op of the straight lines P1 and P2 and the center line Lp and a foot of a perpendicular line drawn from the origin Ov to the center line Lp. In addition, here, the three-dimensional coordinate values of the points P1 and P2 with the origin Ov as the center are represented by (X
1,0, Z1) and (X2,0, Z2).

The calculation using the above equations (1) to (3) is CP
U6, and the result is CRT display 7a,
Display on 7b. Looking at this, the driver adjusts the attitude of the vehicle body 1a so that the values of the inclination θy and the lateral deviation d are both within the allowable range, and enters below the gate type pallet 2. As a result, the vehicle body can easily enter under the pallet without colliding with the front part of the pallet. However, instead of displaying the calculation result, the adjustment of the vehicle body posture may be automatically performed. Here, the point P by the image processor 5
The method of calculating the coordinate values (positions) of 1 and P2 will be described in detail. Figure 5
Shows an example of an image taken by the CCD camera 4.
In the figure, the scattered light from the left and right legs of the pallet is
The polygonal lines SL1 and SL2 are formed on the image (hereinafter referred to as light cutting lines), and the positions of the points P1 and P2 described above correspond to the end points Pg1 and Pg2 of the light cutting lines SL1 and SL2. In the image processor 5, binarization by an appropriate threshold value is performed to extract the light section line, and the end point coordinates Pg1 (Xg1, Yg
1), Pg2 (Xg2, Yg2), and then three-dimensional coordinates (X1, 0, Z1), (X2, 0, Z2) according to the following equation
Respectively.

[Equation 2]

Here, the emission port of the laser light source 3 is the origin O.
In v, α is the angle formed by the CCD camera 4 and the plane of the slit light, and y0 is the distance between the CCD camera 4 and the laser light source 3. Further, b is a parameter of the CCD camera 4, in which the focal length of the camera lens is f and the optical magnification is m.
Then, it is expressed by the following equation. b = f (1 + 1 / m) (6) Next, as shown in FIG. 3B, the vehicle body 1a advances below the gate pallet 2. The operation at this time will be described below. The CCD camera 4 has a pallet inner surface 2
Scattered light from the slit hitting c1 and c2 is shown in FIG.
The images are taken as the light section lines SL3 and SL4 as shown in FIG. The image processor 5 binarizes this image and extracts the light cutting lines SL3 and SL4.
On L4 and on the same scan line (same yg
(P3a, P4a), [P3]
b, P4b], ... Are extracted (see FIG. 6B).

The CPU 6 converts the image coordinate value of the set of these points into the three-dimensional coordinate value centered on the origin Ov (4),
After conversion using the equation (5), the midpoint coordinates of the points of each set are obtained. Since the virtual center line Lp of the gate pallet 2 is obtained as a straight line connecting these midpoint coordinates, the inclination θy and the lateral displacement d of the vehicle body 1a can be calculated from them. It is not possible to detect the vehicle body position in the pallet longitudinal direction, that is, the distance D obtained by the above equation (3) from the light cutting line as shown in FIG. 6, but this is a very important factor during the pallet diving. Don't Therefore, it is sufficient that the driver can judge visually. CRT
Since the displays 7a and 7b are installed in the driver's seats 1b1 and 1b2, respectively, it is possible for the driver to easily get in / out of the pallet regardless of which driver's seat the driver is in. Further, in the above, the outer corner of the leg of the pallet is used as the characteristic point of the pallet detected by the image processor 5, but the characteristic point is not limited to this, and the marker inside the leg or a marker separately attached to the pallet. Anything that can specify the position of the pallet, etc., may be used.

Next, modifications of the present embodiment and examples will be described. (Modification 1) In the above-described embodiment and example, the center of the spread of the slit light is detected in order to detect both the legs 2b1 and 2b2 of the gate type pallet 2 simultaneously by one set of the laser light source 3 and the CCD camera 4. Light in the vicinity is wasted without hitting the palette. Further, when the width Wp of the pallet is relatively wide, it is necessary to widen the angle of view of the CCD camera 4 accordingly, so that distortion of the lens system increases. As a result, the accuracy of measuring the position and orientation of the vehicle body may deteriorate. In such a case, as shown in FIG. 7, two slit light sources 3 and two CCD cameras 4 are installed at the front of the vehicle body, and a point P1 is formed between the light source 3a on the right side in the traveling direction and the CCD camera 4a. Light source 3b on the left side
If the point P2 is detected by the CCD camera 4b and the CCD camera 4b, it is possible to suppress the spread angle of slit light and the increase of the angle of view individually. (Modification 2) In the above-described embodiment and examples, since both the legs 2b1 and 2b2 of the gate type pallet 2 are detected at the same time, the center line Lp can be estimated even if the width Wp of the pallet is unknown. . However, when only a specific type of pallet is used, the width Wp may be known in many cases. At this time, by detecting only one side of the leg portion of the gate type pallet 2 and estimating the center line Lp, it is possible to simplify the apparatus and the image processing. This example is shown in FIG.

Here, the projection direction of the laser light source 3 and C
The imaging axis of the CD camera 4 is installed toward the left leg 2b2 and the inner side wall 2c2 of the portal pallet 2. In the image processor 5, points corresponding to arbitrary two points Q1 and Q2 on the inner wall 2c2 are extracted from the light cutting line, and their three-dimensional coordinate values are Q1 (Xq1, 0, Zq1) and Q2 (X
q2, 0, Zq2) is calculated, and the inclination θy and the lateral displacement d of the vehicle body 1a are calculated by the following equations (see FIG. 9).

[Equation 3] In addition, before the vehicle body 1a dives into the gate type pallet 2,
Since the coordinate value (X2 ', 0, Z2') of the corner P2 'inside the left leg 2b2 of the pallet can be obtained, the distance D between the gate type pallet 2 and the vehicle body 1a can be calculated by the following formula. You can

[0015]

[Equation 4] As described above, according to the present embodiment and the examples or the modified examples, the inclination and the lateral deviation of the vehicle body can be accurately calculated, so that the risk of collision between the pallet and the vehicle body is reduced. In addition, the driver can move in and out of the pallet while checking the display of the relative position and orientation of the vehicle body with respect to the pallet. As a result, in any case, the cargo handling vehicle can be easily driven without relying on the driver's intuition or an assistant.

[0016]

Since the cargo handling vehicle according to the present invention is configured as described above, the vehicle body is the gate type pallet.
Before diving underneath the car and the car body is the gate pallet
In both cases, the risk of collision between the pallet and the car body is reduced because the tilt and the lateral displacement of the car body can be calculated accurately in both cases . In addition, the driver can move in and out of the pallet while checking the display of the relative position and orientation of the vehicle body with respect to the pallet. As a result, in any case, the cargo handling vehicle can be easily driven without relying on the driver's intuition or an assistant.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a cargo handling vehicle 1 according to embodiments and examples of the present invention.

FIG. 2 is a plan view, a front view, and a side view of the cargo handling vehicle 1.

FIG. 3 is an explanatory diagram showing a procedure of diving into a gate pallet.

FIG. 4 is an explanatory diagram showing how to determine the inclination and lateral deviation of the vehicle body.

FIG. 5 is an explanatory diagram showing an image processing result of an imaged optical cutting line.

FIG. 6 is an explanatory diagram of image processing during diving under a palette.

FIG. 7 is an explanatory diagram showing how the cargo handling vehicle according to the first modification dives into the gate pallet.

FIG. 8 is an explanatory diagram showing a state in which a cargo handling vehicle according to a modified example 2 dives into a gate pallet.

FIG. 9 is an explanatory diagram showing how to determine the inclination and lateral deviation of the vehicle body of Modification 2;

FIG. 10 is a schematic diagram showing a schematic configuration of an example of a conventional cargo handling vehicle 1 ′.

[Explanation of symbols]

1 ... Cargo handling vehicle 1a ... Car body 2 ... Gate type pallet 3 ... Laser light source (corresponding to irradiation means) 4 ... CCD camera (corresponding to image pickup means) 5 ... Image processor (corresponding to image analysis means) 6 ... CPU (corresponding to computing means) 7a, 7b ... CRT display (corresponding to display means)

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Koji Yoneda 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo Prefecture Kobe Steel Co., Ltd. Kobe Research Institute (72) Inventor Yutaka Kawada Nishi-ku, Kobe-shi, Hyogo Prefecture 1-5-5 Takatsukadai Kobe Steel Works, Ltd. Kobe Research Institute (56) References JP-A-6-43935 (JP, A) JP-A-5-209746 (JP, A) (58) Survey Areas (Int.Cl. ⁷ , DB name) B60P 1/02 B60P 1/64 B60R 1/00 B25J 5/00

Claims (2)

(57) [Claims] 1. A cargo handling carrier in which a car body is dipped under a gate type pallet consisting of a loading table and legs, and an elevator mechanism provided on the car body lifts and conveys the gate type pallet. An irradiation means for irradiating the slit light diverging in the same plane toward the legs of the mold pallet and a portal pallet which is arranged so that the imaging axis intersects with the above-mentioned plane and is irradiated with the slit light are An image pickup means for picking up an image , an image analysis means for obtaining the position of each point of the gate-shaped pallet by image analysis of the irradiation line on the gate-shaped pallet, and a gate-shaped pallet obtained by the image analysis means. Each point
Under based on the position and a calculating means for calculating the vehicle body relative position and orientation with respect to the gantry pallet, said image analysis means, the body of the gantry pallet
Before diving into one direction, find the position of the feature point of the leg
On the other hand, while the car body is traveling below the gate pallet
Is an arbitrary image on the optical cutting line imaged by the imaging means.
A cargo handling vehicle characterized in that the position of a set of points is obtained. 2. The cargo handling vehicle according to claim 1, further comprising display means for displaying a relative position and orientation of the vehicle body with respect to the gate-shaped pallet.