JPH11291187A - Load position attitude recognizing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the stereoscopic shape of the load top surface in a short time without degrading measuring accuracy. SOLUTION: Wherever a load top surface is positioned at any height within an assumed range from the height of the load on the highest stage to the height of a pallet on the lowest stage, the height of the load top surface is measured at one or more initial slit light projecting angles at which slit light 5 is always irradiated to the load top surface, and any of image data signals from a close- range image pickup device 9a and a long-range image pickup device 9b is selected based on the measured results of the height of the load top surface. After light projection is conducted while the slit light 5 is being projected to the load surface at a slit light projecting angle for actual measurement, and the shape of the load top surface is measured using the selected image data signal, then the cargo 2 to be loaded or unloaded is recognized from the shape of the load top surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cargo position / posture recognition apparatus for use in measuring the three-dimensional position / posture of cargo such as bags or boxes placed on a carrier such as a pallet.

[0002]

2. Description of the Related Art Usually, at the time of shipment from a factory, in order to efficiently carry out a large amount of products, cargo such as bagged products containing products is stacked on a pallet in a plurality of stages, and then transported in pallet units. It is supposed to do. Also, at the time of receiving raw materials at a factory, cargo such as bagging is stacked on a pallet in a plurality of stages and then transported in pallet units. In recent years, the loading and unloading of cargo on pallets has been automated by a handling robot, thereby reducing the work load on the operator and saving labor.

By the way, when the handling robot attempts to carry out the loading / unloading operation, the place position serving as the next loading position or the pick position serving as the next unloading position is determined by the horizontal coordinate and the vertical (height). It is necessary to instruct the handling robot by specifying the coordinates. Therefore, conventionally, the following methods have been proposed so as to recognize a three-dimensional arrangement of cargo and to designate a place position or a pick position.

That is, as shown in FIG. 10, Japanese Unexamined Patent Publication No. 3-23491 discloses a method in which a cargo 51 stacked on a pallet 52 is irradiated linearly with a laser beam 53 from above. Is photographed obliquely from above with one camera 55 having a fixed focus lens to obtain the height position of the cargo 51. Thereafter, the entire cargo 51 is photographed from above, and the unique mark 54 of the cargo 51 in the photographed image is taken.
A method of recognizing a three-dimensional arrangement state of the cargo 51 by detecting a gray-scale image of the cargo 51 by a matching process with a basic mark shape and obtaining a two-dimensional arrangement state is disclosed.

[0005]

However, during the stacking operation and the unloading operation, the height of the cargo 51 is gradually increased or decreased. This needs to be performed based on a captured image captured and captured over a wide range of heights from the upper surface of the highest cargo 51 to the upper surface of the lowest pallet 52. Therefore, in the method of recognizing the three-dimensional arrangement of the cargo 51 with one camera 55 having a fixed focus lens as in the above-described conventional art, for example, the focus of the camera 55 is set so as to photograph the entire cargo 51 at the highest stage. When set, since the data amount indicating each cargo 51 included in the captured image decreases as the distance from the camera 55 increases, especially when the lowest cargo 51 located farthest from the camera 55 is photographed, the cargo 51 However, there is a problem that it is difficult to measure and recognize the three-dimensional arrangement state with high accuracy.

Therefore, it is conceivable to use a camera with an electric zoom lens in place of the camera 55 with a fixed focus lens. However, in this case, the time required for zoom change becomes longer, and the measurement (recognition) time becomes longer. There is.

In recent years, load position and orientation recognition by a light cutting method, in which a plurality of slit lights are sequentially projected on the upper surface of a load and photographed by an imaging device, and the photographed image is processed to measure the upper surface of the load, is performed. Devices are being proposed and adopted. However, even in the case of this device, if it is desired to measure the lowermost cargo upper surface farthest from the imaging device with high accuracy, it is necessary to maintain the data amount of the light emitting interval to be equal to or more than a predetermined value. It is necessary to change the projection angle of the slit light according to the distance.

Accordingly, the present invention provides a cargo position / posture recognition that can measure (recognize) the three-dimensional shape of the upper surface of the cargo (the arrangement of the cargo 51) in a short time without causing a decrease in measurement (recognition) accuracy. It is intended to provide a device.

[0009]

According to a first aspect of the present invention, there is provided a cargo position / posture recognizing apparatus for measuring a shape of a top surface of a stacked cargo and recognizing a cargo to be stacked or unloaded. An illuminating means for projecting a plurality of slit lights on the upper surface of the load by changing the slit light projecting angle, and a short-distance output for outputting an image data signal of a captured image when the slit light reflected on the upper surface of the load is photographed; The slit light is always loaded, regardless of the height of the loading surface at any height from the assumed highest loading height to the lowest pallet height. The upper surface of the cargo is measured at one or a plurality of initial slit light projecting angles applied to the upper surface, and the close-range imaging means and A first image data selection means for selecting one of the image data signals from the long range imaging means,
A distance data calculating unit that shoots the slit light while projecting the slit light at the actual measurement slit light projection angle onto the cargo upper surface and measures the cargo upper surface shape using a selected image data signal, and from the cargo upper surface shape. And a packing form recognizing means for recognizing the cargo to be stacked or unloaded.

According to the above arrangement, if the distance from the upper surface of the load to each image pickup means is short, the image data signal of the short distance image pickup means can be selected based on the measurement result of the load upper surface height. If the distance from the upper surface of the load to each image pickup means is long, the image data signal of the long distance image pickup means can be selected. Therefore, even if the load upper surface height changes in the range from the highest load height to the lowest pallet height, an image data signal of a captured image in which the image area of the load upper surface becomes a large part is obtained. The cargo to be stacked or unloaded can be recognized. As a result, an image data signal of a portion necessary for recognition can always be obtained with a sufficient data amount, so that the load upper surface can be measured and recognized with high accuracy with a small memory capacity at all load upper surface heights. Further, since the image data signal can be selected by switching between the short-distance imaging unit and the long-distance imaging unit, it is possible to select an image data signal by changing the zoom using a camera with an electric zoom lens and obtaining an image data signal. Also, the image data signal can be obtained in a short time, and the recognition time can be reduced.

According to a second aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the first aspect, wherein a slit light projection interval is obtained based on a measurement result of the upper surface height of the cargo by the first image data selecting means. It is characterized in that it has a first projection angle calculating means for calculating a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals. According to the above configuration, even when the load height changes greatly for each pallet, a plurality of slit light projecting angles corresponding to the slit light projecting intervals on the upper surface of the load are calculated. The three-dimensional coordinate values can be measured at a predetermined density without being affected, and as a result, the measurement accuracy can always be kept high.

According to a third aspect of the present invention, there is provided the cargo position / posture recognizing device according to the first or second aspect, wherein the image processing in the captured image is performed based on the measurement result of the upper surface height of the cargo by the first image data selecting means. The image processing apparatus further includes a first image processing area limiting unit that determines an area and limits an image data signal used by the distance data calculation processing unit to an image data signal corresponding to the image processing area. According to the above configuration, the measurement can be performed using the image data signal of a small data amount limited to the image processing area,
Processing time can be reduced.

According to a fourth aspect of the present invention, there is provided the cargo position / posture recognizing device according to any one of the first to third aspects, wherein the cargo height of the cargo to be loaded or unloaded detected last time is defined as a cargo upper surface height. And a second image data selecting means for selecting one of the image data signals from the short-distance imaging means and the long-distance imaging means based on the cargo upper surface height. . According to the above configuration, it is possible to measure the shape of the next load upper surface earlier than in the case where the slit light projected on the load upper surface is photographed and the height of the load upper surface is actually obtained.

According to a fifth aspect of the present invention, there is provided the cargo position / posture recognizing device according to the fourth aspect, wherein a slit light projection interval is obtained based on the upper surface height of the load obtained by the second image data selecting means. It is characterized by having a second projection angle calculation means for calculating a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals. According to the above configuration,
When the load height changes sequentially due to stacking or unloading, a plurality of slit light projection angles corresponding to the slit light projection intervals optimal for the load upper surface height can be calculated.
Therefore, the three-dimensional coordinate value can be obtained at a predetermined density without being affected by the change in the cargo height, and as a result, the measurement accuracy can be always kept high.

According to a sixth aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the fourth or fifth aspect, wherein the image processing area in the photographed image is based on the upper surface height of the cargo obtained by the second image data selecting means. And a second image processing area limiting means for limiting an image data signal used in the distance data calculation processing means to an image data signal corresponding to the image processing area. According to the above configuration,
When the load height changes sequentially due to stacking and unloading, determine the optimal image processing area for the upper surface of the load, and perform measurement using image data signals with a small amount of data limited to this image processing area Therefore, the processing time can be reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the cargo position / posture recognition apparatus according to the present embodiment includes a pallet 1
It has a sensor head mechanism 3 installed above the bag-like cargo 2 stacked above, and a recognition processing control panel 4 connected to the sensor head mechanism 3. Sensor head mechanism 3
As shown in FIG. 2, a slit light projector 6 that emits while diffusing the slit light 5 composed of a belt-like laser light
A reflecting mirror 7 for reflecting the slit light 5 from the slit light projector 6 in the cargo 2 direction, a stepping motor 8 capable of arbitrarily changing the inclination angle of the reflecting mirror 7, and a slit light 5 projected on the cargo 2 Short-range imaging device 9 for photographing
a and a long-distance imaging device 9b.

As shown in FIG. 1, the above-described short-distance imaging device 9a has a wide-angle lens 10a and an imaging member 11, and is used when photographing a high position (step) close to the imaging device 9a. It has become. On the other hand, the long-distance imaging device 9b has a telephoto lens 10b and an imaging member 11, and is used at the time of photographing a low position (stage) separated from the imaging device 9b. These imaging devices 9
a · 9b wide-angle lens 10a and telephoto lens 10b
Indicates that the shooting direction is vertical (Z direction), as shown in FIG.
It is set to be. In addition, each imaging device 9a
The imaging member 11 of 9b has an imaging surface 11a on which the slit light 5 projected on the cargo 2 via the lens 10 is formed, and the imaging surface 11a is in a vertical direction (Z direction). It is set to be vertical. An image is projected on the imaging surface 11a of the imaging member 11 in a point-symmetric manner with respect to the lens center O. For example, the irradiation line 5 formed by irradiating the cargo 2 with the slit light 5 is formed. Q ₁
Point, Q ₂ points, Q ₃ points, P ₁ point each, P ₂ point, P ₃
An image is formed on the imaging surface 11a as a point.
Although not shown in FIG. 3, the lenses 10a and 10b
By installing an optical bandpass filter such as an interference filter in front, it is possible to form only the image of the slit light 5 on the imaging surface 11a.

The image pickup member 11 has a plurality of light receiving element portions (pixels) for generating electric charges corresponding to the amount of light in a matrix in the X and Y directions. And sequentially output as image data. And each imaging device 9
The output signals from the imaging members 11a of FIG.
Is connected to the recognition processing control panel 4 as shown in FIG.

The recognition processing control panel 4 includes both image pickup members 11.1
It has an image data switch 19 for switching the image data signal from the first unit 1 and an I / O unit 12a connected to the image data switch 19, the slit light projector 6, and the like.
The image data switch 19 includes input terminals 19a and 19b for inputting image data signals from the imaging members 11 and 11 of the imaging devices 9a and 9b, and input terminals 19a and 1b.
Output terminal 1 switchably connected to one of the terminals 9b
9c, input terminals 19a and 19b, and output terminal 19c.
And a switching terminal 19d for switching the connection state between them. The output terminal 19c and the switching terminal 19d
Is connected to the I / O unit 12a, and the image data switching unit 19 enters a connection state according to the switching signal when the switching signal from the I / O unit 12a is input to the switching terminal 19d. One of the image data signals input from the imaging devices 9a and 9b by the I / O unit 12
a.

Further, in addition to the image data switch 19 and the I / O unit 12a, the recognition processing control panel 4 includes an I / O
An I / O unit 12b connected to the O unit 12a via a signal bus 14, a motor driving unit 13, an arithmetic unit 16, a RAM 17,
And a ROM 18. An image data storage area 17a is formed in the RAM 17 so as to have a matrix-like data table in the X and Y directions that matches the arrangement of the light receiving elements of the imaging member 11. In the image data storage area 17a, the image data from the above-described imaging devices 9a and 9b input via the I / O unit 12a is stored. Further, a distance data storage area 17b is formed in the RAM 17, and three-dimensional coordinates (distance data) of the upper surface of the cargo 2 are stored in the distance data storage area 17b.

On the other hand, the ROM 18 stores an image processing routine for selecting the most suitable image pickup devices 9a and 9b for the load height and detecting the load position and attitude. The image processing routine performs an image device selection process, a mirror angle calculation process, an image processing region limitation process, a distance data calculation process, and a package appearance recognition process.

That is, the image device selection process is performed in steps S3 to S3 in FIG.
The image data signal output from the short-distance imaging device 9a is used for the three-dimensional measurement of the upper surface of the cargo based on the cargo height obtained by the initial measurement, or the long-distance imaging device corresponds to S7. It is determined whether to use the image data signal output from 9b, and the image data switch 19 is controlled based on the determination result. The mirror angle calculation process corresponds to step S8 in FIG. 4, and calculates a plurality of mirror angles for projecting the slit light 5 at regular intervals on the upper surface of the load based on the load height obtained by the initial measurement. It has become. The image processing area limitation processing is performed in S of FIG.
Image processing is performed on the image data stored in the image data storage area 17a, which corresponds to 9 parts, and the image processing area is limited based on the cargo height obtained by the initial measurement when obtaining the slit light center position in the image. It is supposed to. The distance data calculation process corresponds to S10 to S13 in FIG.
The slit light center position is obtained by image processing, and distance data is calculated by triangulation. The package appearance recognition processing corresponds to step S14 in FIG. 5, and calculates the arrangement state, picking position, and attitude of the cargo 2 based on the three-dimensional coordinate values of the upper surface of the cargo stored in the distance data storage area 17b. It has become.

The recognition processing control panel 4 having the above configuration is
It is connected to the robot control panel 20 via the I / O unit 12b. The robot control panel 20 includes a handling robot 21 installed near the pallet 1 as shown in FIG.
It is connected to the. In addition, a roller conveyor 22 and the like for transferring the cargo 2 are disposed near the handling robot 21. Then, when receiving the recognition data from the recognition processing control panel 4, the robot control panel 20 determines the picking position of the next cargo 2 and transfers the cargo 2 existing at this picking position to the roller conveyor 22 or the like. Thus, a command is issued to the handling robot 21.

The operation of the cargo position / posture recognition apparatus having the above configuration will be described with reference to the flow charts of FIGS.

First, as shown in FIGS. 1 and 2, when the pallet 1 is carried into a predetermined position below the sensor head mechanism 3 (S1), the robot control panel 20 initializes the recognition processing control panel 4 with respect to the initial position. An instruction signal is transmitted to start the measurement (S2).

Upon receiving the instruction signal, the recognition processing control panel 4 converts the image data signal output from the short-distance imaging device 9a and the image data signal output from the long-distance imaging device 9b based on the load height. A first purpose of judging which one should be used for measuring the distance data on the upper surface of the load from the field-of-view size of the wide-angle lens 10a and the telephoto lens 10b and the measurement resolution in the depth direction; A second purpose of calculating a mirror angle at which a plurality of slit light beams 5 at a distance can be projected, and a processing time is reduced by limiting an image processing area for detecting a slit light center line based on a load height. In order to achieve the third object and the following, first, an initial measurement of the cargo height is performed.

That is, an output signal is output to the slit light projector 6 so that the slit light 5 is emitted from the slit light projector 6, and an image data signal from the short-range imaging device 9a is fetched. A switching signal is output to the image data switch 19. Further, the stepping motor 8 is driven to rotate so as to have a preset initial measurement mirror angle. As a result, the slit light 5 emitted from the slit light projector 6 reaches the reflection mirror 7 while diffusing in a band shape, is reflected in the direction of the pallet 1, and linearly extends to both ends of the pallet 1 and the cargo 2 on the pallet 1. It will be projected (S3).

Next, the whole of the pallet 1 or the cargo 2 on which the slit light 5 is projected is photographed by the short-distance imaging device 9a. Here, the initial measurement mirror angle that determines the reflection angle of the slit light 5 is determined by the slit, regardless of the height of the cargo upper surface at any height from the highest cargo height to the lowest pallet height. One or a plurality of angles at which the light 5 always hits the upper surface of the cargo are set.

An image data signal obtained by photographing the projection line 5a of the slit light 5 projected at the initial measurement mirror angle by the short-range imaging device 9a is recognized through the image data switch 19 and the I / O unit 12a. It is taken into the control panel 4 and stored in the image data storage area 17a of the RAM 17. Thereafter, the light projecting line 5a of the slit light 5 from the image data of the image data storage area 17a is specified, the center of each point of the projection line 5a (e.g. _{P 1 · P 2 · P 3} ) and wide-angle lens 10a The line of sight connecting the point O (for example, L ₁
L ₂ · L ₃ ) is required. Then, after the slit light plane S of the slit light 5 is obtained based on the above-described initial mirror measurement angle and the rotation axis position of the reflection mirror 7, the intersection (for example, Q _{1) of the} slit light plane S and the line of sight is obtained.・ Q ₂
The three-dimensional position of Q ₃ ) is obtained as distance data (X, Y, Z), and the initial measurement result of the load height is the average load height Z.
It is calculated as init (S4).

The load average height Zinit is compared with the imaging device switching height threshold value Zth set in advance from the field size and the measurement resolution in the depth direction (S5). Load average height Zin
If it is less than the imaging device switching height threshold value Zth (S5, YES), the arithmetic unit 16 controls the image data switch 19 via the I / O unit 12a, and the It is set so that the captured image data signal is taken into the recognition processing control panel 4 (S6). On the other hand, when the average cargo height Zinit is equal to or greater than the imaging device switching height threshold value Zth (S5, NO), the arithmetic unit 16 controls the image data switch 19 via the I / O unit 12a, and It is set so that the image data signal photographed by the distance imaging device 9b is taken into the recognition processing control panel 4 (S7). As a result,
High measurement resolution can be ensured in a wide range of height from the assumed highest loading height to the lowest pallet height.

Next, based on the load average height Zinit, FIG.
As shown in (5), the mirror angles θ _{1 to} θn are calculated so that the plurality of slit lights 5 are projected on the upper surface of the cargo at regular intervals (S8). Further, an image processing area for obtaining the slit light center line by image processing is obtained for each of the captured images at the mirror angles θ _{1 to} θn that project the plurality of slit lights 5. The reason why the image processing area can be obtained for each captured image at each of the mirror angles θ _{1 to} θn is that, as shown in FIG. 6, the existence range of the slit light image on the imaging member 11 is equal to the load average height Zinit. This is because the limitation can be made based on the height H of the cargo 2 and the mirror rotation angle (S9).

When the above measurement processing is completed, as shown in FIG. 7, distance data measurement processing for obtaining three-dimensional coordinates (positions) of a point sequence along a plurality of light emitting lines 5a formed at equal intervals is executed. Is done.

That is, for example, when the short-distance imaging device 9a is selected as a result of the initial measurement, first, the stepping is performed so that the inclination angle of the reflection mirror 7 corresponding to the mirror angle θ ₁ calculated in the initial measurement is obtained. When the drive output is output from the motor drive unit 13 to the motor 8, the stepping motor 8 is rotationally driven (S10).

When the reflection mirror 7 is set at a predetermined inclination angle by the rotational driving of the stepping motor 8, the slit light 5 emitted while being spread in a band shape from the slit light projector 6 is emitted from the reflection mirror 7 in the direction of the pallet 1. The light is reflected and projected linearly to both ends of the pallet 1 and the cargo 2 on the pallet 1. Then, the whole of the pallet 1 and the cargo 2 on which the slit light 5 is projected in this manner is photographed by the short-range imaging device 9a (S11).

An image data signal photographed by the short-distance imaging device 9a is supplied to an image data switch 19 and an I / O
It is taken into the recognition processing control panel 4 via the O section 12a, and R
The image data is stored in the image data storage area 17a of the AM 17. Thereafter, as shown in FIG. 8, image data corresponding to the image processing area in the case of the mirror angle θ ₁ obtained by the initial measurement is extracted from all the image data in the image data storage area 17a, and this image data is Based on this, the projection line 5a of the slit light 5 is specified. Then, as shown in FIG. 3, each point of the projection line 5a (e.g. _{P 1 · P 2 · P 3} ) and line-of-sight line connecting the center point O of the wide-angle lens 10a (e.g. L ₁ ·
After obtaining L ₂ · L ₃ ), the slit light plane S of the slit light 5 is obtained based on the above-described initial measurement mirror angle and the rotation axis position of the reflection mirror 7. Then, the intersection (for example, Q ₁ , Q ₂ ,
The three-dimensional position of Q ₃ ) is obtained as distance data (X, Y, Z) and stored in the distance data storage area 17b of FIG. 1 (S12).

Next, it is determined whether or not the measurement by calculating the three-dimensional coordinates of the light projecting line 5a (slit light reflection position) has been performed at all the mirror angles θ _{1 to} θn (S13). ). Unmeasured mirror angle θ ₁ ~
if θn is present (S13, NO), 3-dimensional position is determined for mirror angle θ ₁ ~θn unmeasured rerun from S10. On the other hand, all mirror angles θ _{1 to} θ
When the measurement for n is completed (S13, YE
S), it is determined that the three-dimensional positions of the point sequence along the plurality of light emitting lines 5a formed at equal intervals have been obtained, and as shown in FIG. 9, pattern matching or the like is performed using these three-dimensional positions. Object placement recognition processing is performed. Then, the cargo 2 to be unloaded is selected from the measurement data obtained by this processing, and the three-dimensional position / posture of the selected cargo 2 is detected. At the time of this detection, it is also determined whether or not the cargo 2 to be unloaded is the last cargo on the pallet 1 (S14).

Next, the three-dimensional position / posture of the cargo 2 to be unloaded is transmitted from the recognition processing control panel 4 to the robot control panel 20 as a picking position. A final cargo signal indicating this is also transmitted (S15). Then, the robot control panel 20 that has received the three-dimensional position and orientation of the cargo 2
1 to control the handling robot 21
The cargo 2 is unloaded (S16).

When the unloading operation is completed, the robot control panel 20 checks whether or not the final cargo signal has been input, and if it is determined that the final cargo 2 has been completely unloaded by inputting the final cargo signal, the robot control panel 20 unloads. Finish the work. On the other hand, if the final cargo signal is not input, it is determined that the cargo 2 is present on the pallet 1 and an instruction signal is transmitted to the recognition processing control panel 4 to start the next measurement (S17).

The recognition processing control panel 4, which has received the second and subsequent instruction signals, does not perform the initial measurement (S3 to S4) as performed in the first measurement, but the load average height Z of the initial measurement result.
Init is replaced with the height Z of the cargo 2 to be unloaded obtained in the previous measurement (S18). Then, the process is re-executed from S5, and the height Z of the cargo 2 (load average height Zinit) is used for comparison with the imaging device switching height threshold value Zth, and the short-distance imaging device 9a and the long-distance imaging device 9b are used. After selecting the image data signal output from (S5 to S7), a series of processes such as calculation of the mirror angle (S8) and limitation of the image processing area for each mirror angle (S9) are performed, 3D position / posture of the cargo 2 to be unloaded (S9)
~ S14).

Thereafter, the unloading based on the three-dimensional position / posture of the cargo 2 is repeatedly performed until it is determined in S14 that the cargo 2 is the final cargo 2, so that all the cargo 2 on the pallet 1 is removed. It will be unloaded.

Although the present invention has been described based on the preferred embodiments, the present invention can be modified without departing from the spirit of the present invention.

That is, the cargo position / posture recognition device measures the shape of the top surface of the cargo and recognizes the cargo (cargo 2) to be loaded or unloaded, and changes the slit light projection angle (mirror angle). Means for projecting a plurality of slit lights 5 on the upper surface of the cargo (slit light projector 6)
And a short-distance imaging unit (a short-distance imaging device 9a) and a long-distance imaging unit (a long-distance imaging device) that respectively output image data signals of a captured image when the slit light 5 reflected on the upper surface of the cargo is captured. 9b) and in any case where the load upper surface height is in the range from the assumed highest load height to the lowest pallet height, the slit light 5 is always applied to the load upper surface. One or more initial slit light projection angles (initial measurement mirror angles) are used to measure the height of the cargo surface, and based on the measurement results of the height of the cargo surface, the short-distance imaging means and the long-distance imaging means measure And the first image data selecting means (S4 to S7 in FIG. 4) for selecting any one of the image data signals, and projecting the slit light 5 on the upper surface of the cargo at the slit light projection angle for actual measurement (mirror angles θ _{1 to} θn). Shoot while shining, Distance data calculating means for measuring the shape of the upper surface of the load using the selected image data signal (FIG. 5)
S10 to S13) and a packing form recognition means (S in FIG. 5) for recognizing the cargo to be stacked or unloaded from the top shape of the cargo.
14).

According to the above configuration, based on the measurement result of the upper surface of the load, if the distance from the upper surface of the load to each image pickup means is short, the image data signal of the short distance image pickup means can be selected. If the distance from the upper surface of the load to each image pickup means is long, the image data signal of the long distance image pickup means can be selected. Therefore, even if the load upper surface height changes in the range from the highest load height to the lowest pallet height, an image data signal of a captured image in which the image area of the load upper surface becomes a large part is obtained. The cargo to be stacked or unloaded can be recognized. As a result, an image data signal of a portion necessary for recognition can always be obtained with a sufficient data amount, so that the load upper surface can be measured and recognized with high accuracy with a small memory capacity at all load upper surface heights. Further, since the image data signal can be selected by switching between the short-distance imaging unit and the long-distance imaging unit, it is possible to select an image data signal by changing the zoom using a camera with an electric zoom lens and obtaining an image data signal. Also, the image data signal can be obtained in a short time, and the recognition time can be reduced.

Further, the cargo position / posture recognition device obtains a slit light projection interval based on the measurement result of the cargo upper surface height by the first image processing selecting means, and calculates a plurality of actual measurement intervals corresponding to the slit light projection interval. It is preferable to have a first projection angle calculation means (S8 in FIG. 4) for calculating the slit light projection angle. With this configuration, even when the load height changes greatly for each pallet 1, a plurality of slit light projecting angles corresponding to the slit light projecting intervals on the upper surface of the load are calculated. Without being affected by the change, it is possible to measure three-dimensional coordinate values at a predetermined density,
As a result, the measurement accuracy can always be kept high.

The cargo position / posture recognition device obtains an image processing area in the photographed image based on the measurement result of the cargo upper surface height by the first image processing selection means, and obtains an image data signal used by the distance data calculation processing means. It is preferable to have first image processing area limiting means (S9 in FIG. 4) for limiting the image data signal to an image data signal corresponding to the image processing area. With this configuration, the measurement can be performed using an image data signal of a small data amount limited to the image processing area, so that the processing time can be further reduced.

The loading position / posture recognizing device sets the cargo height of the cargo to be stacked or unloaded detected last time as the loading upper surface height, and based on the loading upper surface height, the short-distance imaging means and the long-distance imaging means. A second image processing selecting means (S18 in FIG. 5,
It is preferable to have S5 to S7 in FIG. With this configuration, the next measurement of the top surface of the load can be performed earlier than in the case where the slit light 5 projected on the top surface of the load is photographed and the height of the top surface of the load is actually obtained. .

Further, the cargo position / posture recognizing device calculates a slit light projection interval based on the cargo upper surface height determined by the second image processing selecting means, and a plurality of actual measurement slits corresponding to the slit light projection interval. It is preferable to have a second light projection angle calculation means (S18 in FIG. 5, S8 in FIG. 4) for calculating the light projection angle. And if it is a structure, when the load height changes sequentially by stacking and unloading, it is possible to calculate a plurality of slit light projecting angles corresponding to the slit light projecting intervals optimal for the load upper surface height. . Therefore, the three-dimensional coordinate value can be obtained at a predetermined density without being affected by the change in the cargo height, and as a result, the measurement accuracy can be always kept high.

The load position / posture recognizing device obtains an image processing area in the photographed image based on the load upper surface height obtained by the second image processing selecting means, and converts the image data signal used by the distance data calculating processing means. Second image processing area limiting means for limiting to an image data signal corresponding to the image processing area (FIG. 5)
(S18 in FIG. 4 and S9 in FIG. 4).
With this configuration, when the load height changes sequentially due to stacking or unloading, an image processing area optimal for the upper surface of the load is obtained, and image data of a small data amount limited to this image processing area is obtained. Since measurement can be performed using signals, the processing time can be reduced.

[0049]

According to the first aspect of the present invention, there is provided a cargo position / posture recognizing device for measuring the shape of a loaded cargo surface and recognizing the cargo to be loaded or unloaded. Illuminating means for projecting the slit light of the book, short-distance imaging means and long-distance imaging means for outputting an image data signal of a captured image when the slit light reflected on the cargo upper surface is captured, respectively, are assumed. The slit light is always applied to the upper surface of the load, regardless of the height of the upper surface of the load at any height from the highest load height to the lowest pallet height. The upper surface height of the cargo is measured at the slit light projection angle, and based on the measurement result of the upper surface height of the cargo, an image data signal from the short-range imaging unit and the long-range imaging unit is obtained. First image processing selecting means for selecting the image, and photographing the slit light while projecting the slit light onto the upper surface of the cargo at an actual slit light projection angle, and measuring the shape of the upper surface of the cargo using the selected image data signal. And a packing form recognizing means for recognizing the cargo to be stacked or unloaded from the shape of the cargo upper surface.

According to the above configuration, even if the upper surface of the load changes in the range from the highest load height to the lowest pallet height, the image data signal required for recognition is always sufficient. Since the load amount can be obtained, the load upper surface can be measured and recognized with high accuracy with a small memory capacity at all load upper surface heights. Further, since the image data signal can be selected by switching between the short-distance imaging unit and the long-distance imaging unit, an effect is obtained that the image data signal can be obtained in a short time and the recognition time can be shortened.

According to a second aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the first aspect, wherein a slit light projection interval is obtained based on a measurement result of the upper surface height of the cargo by the first image processing selecting means. This is a configuration having first projection angle calculating means for calculating a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals. According to the above configuration, even when the load height changes greatly for each pallet, a plurality of slit light projecting angles corresponding to the slit light projecting intervals on the upper surface of the load are calculated. It is possible to measure three-dimensional coordinate values at a predetermined density without being affected, and as a result, there is an effect that the measurement accuracy can always be kept high.

According to a third aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the first or second aspect, wherein the image processing in the photographed image is performed based on the measurement result of the upper surface height of the cargo by the first image processing selecting means. The image processing apparatus includes a first image processing area limiting unit that determines an area and limits an image data signal used by the distance data calculation processing unit to an image data signal corresponding to the image processing area. According to the above configuration, the measurement can be performed using the image data signal having a small data amount limited to the image processing area, and thus the processing time can be shortened.

According to a fourth aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to any one of the first to third aspects, wherein the cargo height of the cargo to be loaded or unloaded detected last time is regarded as the top surface height of the cargo. And a second image processing selecting means for selecting one of the image data signals from the short-distance imaging means and the long-distance imaging means based on the cargo upper surface height. According to the above configuration, it is possible to measure the next cargo upper surface shape earlier than in the case where the slit light projected on the cargo upper surface is photographed and the cargo upper surface height is actually obtained. To play.

According to a fifth aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the fourth aspect, wherein the slit light projection interval is obtained based on the load upper surface height obtained by the second image processing selecting means. This is a configuration having a second projection angle calculating means for calculating a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals. According to the above configuration, when the load height changes sequentially due to stacking and unloading, it is possible to calculate a plurality of slit light projecting angles corresponding to the slit light projecting intervals optimal for the load upper surface height. . Therefore, three-dimensional coordinate values can be obtained at a predetermined density without being affected by a change in the cargo height, and as a result, there is an effect that the measurement accuracy can always be kept high.

According to a sixth aspect of the present invention, there is provided the cargo position / posture recognition apparatus according to the fourth or fifth aspect, wherein the image processing area in the photographed image is based on the cargo upper surface height obtained by the second image processing selecting means. And a second image processing area limiting means for limiting an image data signal used in the distance data calculation processing means to an image data signal corresponding to the image processing area. According to the above configuration, when the load height changes sequentially due to stacking or unloading, an image processing area optimal for the upper surface of the load is obtained, and an image data signal of a small data amount limited to this image processing area is obtained. Since the measurement can be performed by using, there is an effect that the processing time can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a recognition processing control panel.

FIG. 2 is an explanatory diagram showing a state of unloading.

FIG. 3 is an explanatory diagram illustrating a calculation principle of distance data.

FIG. 4 is a flowchart showing a part of an unloading operation procedure.

FIG. 5 is a flowchart showing a part of an unloading operation procedure.

FIG. 6 is an explanatory diagram showing a state in which a load average height is obtained.

FIG. 7 is an explanatory view showing a state in which slit light is projected at intervals corresponding to the height of the cargo upper surface.

FIG. 8 is an explanatory diagram illustrating an image processing area.

FIG. 9 is an explanatory diagram showing a state of distance data.

FIG. 10 is an explanatory diagram showing a state where cargo is transferred by a conventional recognition process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pallet 2 Cargo 3 Sensor head mechanism 4 Recognition processing control panel 5 Slit light 6 Slit light projector 7 Reflection mirror 8 Stepping motor 9a Close-range imaging device 9b Long-range imaging device 11 Imaging member 13 Motor drive unit 14 Signal bus 16 Calculation Unit 17 RAM 18 ROM 19 Image data switching unit 20 Robot control panel 21 Handling robot 22 Roller conveyor

Claims (6)

[Claims] 1. A method of measuring the shape of a top surface of a stacked load,
A loading position / posture recognition device for recognizing a cargo to be stacked or unloaded, an illumination means for projecting a plurality of slit lights on the upper surface of the load by changing a slit light projection angle, and capturing the slit light reflected on the upper surface of the load. A short-distance imaging unit and a long-distance imaging unit that respectively output image data signals of the captured image when the image is captured, and the height of any of the range from the assumed highest cargo height to the lowest pallet height. Even when there is a load upper surface height, the load upper surface is measured at one or a plurality of initial slit light projection angles at which the slit light is always applied to the load upper surface, and the load upper surface height is measured. First image data selecting means for selecting one of the image data signals from the short-distance imaging means and the long-distance imaging means based on the result; A distance data calculating means for photographing while projecting onto the upper surface of the load at the lit light projection angle and measuring the shape of the upper surface of the load using the selected image data signal; and an object for loading or unloading from the upper surface shape of the load. A cargo position / posture recognizing device, comprising: a cargo form recognizing means for recognizing cargo. 2. A slit light projection interval is obtained based on a measurement result of a cargo upper surface height by the first image data selecting means, and a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals are calculated. 2. The cargo position / posture recognition apparatus according to claim 1, further comprising a first light projection angle calculation means for calculating. 3. An image processing area in a photographed image is obtained based on a measurement result of the upper surface height of the cargo by the first image data selecting means, and an image data signal used in the distance data calculating processing means is converted into the image processing area. 3. The cargo position / posture recognition apparatus according to claim 1, further comprising a first image processing area limiting unit for limiting the image data signal to an image data signal corresponding to the first and second image data signals. 4. The cargo height of the cargo to be loaded or unloaded detected last time is defined as a cargo upper surface height, and image data from the short distance imaging means and the long distance imaging means are determined based on the cargo upper surface height. Second to select one of the signals
The cargo position / posture recognition apparatus according to any one of claims 1 to 3, further comprising image data selection means. 5. A slit light projection interval is calculated based on the cargo upper surface height determined by the second image data selection means, and a plurality of actual measurement slit light projection angles corresponding to the slit light projection intervals are calculated. 5. The cargo position / posture recognition apparatus according to claim 4, further comprising a second light projection angle calculation means for performing the calculation. 6. An image processing area in a photographed image is obtained based on the cargo upper surface height obtained by said second image data selecting means, and an image data signal used by said distance data calculation processing means is stored in said image processing area. 6. The cargo position / posture recognition apparatus according to claim 4, further comprising a second image processing area limiting means for limiting the image data signal to a corresponding image data signal.