JPS62161004A - Method and apparatus for illuminating image sensor - Google Patents

Abstract

PURPOSE:To always irradiate constant illumination light regardless of the distacne between an object and a TV camera, by detecting the distance data between the TV camera and the object and controlling the quantity and illumination direction of illumination light on the basis of said data. CONSTITUTION:A data latch 11 preliminarily stores the order value 2a corresponding to the distance l between a TV camera 7 and each of parts 8a-8c and the distance fl between the camera 7 and an illuminator 5 from a robot control apparatus 2. When the first order value 2a and the order value changed with respect to said value 2a are inputted, these values are sent to a data converting circuit 12. The circuit 12 preliminarily calculates the relation between the distance fl, l and the quantity of illumination light to the parts 8a-8c to store the same and sends the data corresponding to the quantity of illumination light to a variable power source 13 on the basis of the order value 2a from the latch. The power source 13 sends the current or voltage corresponding to the predetermined quantity of light to the illuminator 5 on the basis of the data from the circuit 12. By this method, an illumination light quantity control apparatus 10 can illuminate the parts 8a-8c with an optimum quantity of illumination light from the illuminator 5.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention holds an image sensor such as a TV camera at the hand of a robot, and uses pattern recognition to detect the shape and position of an object or to determine the appearance of the object. The present invention relates to a recognition system, and in particular to an image sensor illumination method and apparatus suitable for always providing stable and constant illumination light during pattern recognition regardless of the distance between a TV camera and an object.

[Background of the invention]

In the conventional robot 1 visual lighting method, for example, [Robot Vision 1
983, pages 305 to 311, P, F, Hyukin and H, F, Fuchs (P, F, Hev
“OMS-Vision System” (OMS-Vision System) by Kin and H, J, Fuchs)
As introduced in the document entitled SYSTEM) J, a method is used in which illumination light is applied to the entire working range of a recognition target from a fixed position outside the working range of the robot.

However, with the above method, it is difficult to uniformly illuminate the entire target range, so in robot vision, the input image size is often only a portion of the target recognition range, and it is difficult to move the robot. When a part of the images within one working range is inputted using the conventional method, the brightness differs for each input image, resulting in a drawback such as a decrease in pattern recognition accuracy.

Also, due to differences in the size of things recognized.

When the distance between the recognition target and the TV camera changes, the brightness changes each time, which further deteriorates the recognition accuracy.

Also, even if you attach a lighting device to the robot's hand to illuminate it,
Although the distance between the recognition target and the TV camera is within a certain narrow range, there are drawbacks such as the fact that appropriate illumination conditions are not met.

[Purpose of the invention]

An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a simple method that always applies constant illumination light regardless of the distance between the recognition target and the TV camera, without reducing the recognition accuracy of robot visual recognition. An object of the present invention is to provide an illumination method for an image sensor and a device thereof that enable pattern recognition processing.

[Summary of the invention]

To achieve the above object, the present invention includes a pattern recognition method in which an object requiring illumination light is converted into an electrical signal by a photoelectric sensor, and distance data between the photoelectric sensor and the object is detected.

The feature is that the amount and direction of the illumination light is controlled based on this distance data, the illumination light illuminates the same area as the input field of view of the TV camera, and the object is always illuminated under constant optimal illumination conditions. A preferred implementation device is a pattern recognition device that recognizes a pattern by converting an object that requires illumination light into an electrical signal using a photoelectric sensor, which includes an illumination mechanism that illuminates the object with illumination light; A detection mechanism that detects distance data between the photoelectric sensor and the target object, and a direction of illumination light from the illumination mechanism based on the detection result of the distance data by this detection mechanism to be in the same area as the input field of view of the photoelectric sensor. The present invention is characterized in that it is provided with a control mechanism that controls the brightness of the illumination light from the illumination mechanism based on the detection result of the distance data.

[Embodiments of the invention]

1 to 3 showing embodiments of the present invention will be described below. FIG. 1 is a perspective view showing the case where the illumination device for the image sensor according to the present invention is attached to the robot 1, FIG. 2 is an enlarged explanatory view showing the illumination device for the image sensor shown in FIG. 1, and FIG. FIG. 3 is an enlarged explanatory diagram showing the illumination light amount control device and the illumination angle control device shown in FIG. 2;

In Fig. 1, 1 is a robot, and the hand 3 is moved in the direction of arrow A (vertical direction) according to a command from the robot control device M2.
It is formed so that it can be moved freely. 4 is a base, which is fixedly supported by the hand 3, and includes a lighting device 5 and a driving device for the lighting device! 6 and a TV camera 7 are placed thereon. lighting system w5
is a driving device for lighting equipment! 6, it is formed so that it can be rotated in the direction of arrow B to adjust its optical axis 6a.

In addition, the illumination light amount can be adjusted based on a command from an illumination light amount control device (described later). The illumination device driving device 6 is formed of, for example, a motor, and rotates in response to a command from an illumination angle control device (described later) to rotate the illumination device 5 by a predetermined angle. 8a, 8b.

8c is the part to be recognized, and C is
It travels in the direction of the arrow and stops at a predetermined position. ↓ Stand is the illumination light amount control device, data latch 11,
It is formed from a data conversion circuit 12 and a variable power supply 13. The data latch 11 is connected to each part 8a, 8b from the TV camera 7 from the robot control device 2 in advance.

The command value 2a corresponding to the distance Q and the distance ffl between the TV camera 7 and the lighting device 5 is stored up to 8c, and when the initial command value 2a and the command value changed from the command value 2a are input, the data The signal is sent to the conversion circuit 12. The data conversion circuit 12 determines in advance the distance fQ between the TV camera 7 and the lighting device 5, and the distance fQ between the TV camera 7 and the lighting device 5.
and distance #IQ between parts 8a, 8b, 8c and illumination device 5
Amount of illumination light (brightness) from to parts 8a, 8b, and 8c
The relationship between the two is calculated and stored as a data table, and data corresponding to the amount of illumination light is sent to the variable power source 13 based on the command value from the data latch 11. The variable power supply 13 controls the current or voltage based on the data from the data conversion circuit 12, and sends the current or voltage corresponding to a predetermined amount of light to the lighting device 5. Therefore, the illumination light amount control device ↓ is the distance 1 between the TV camera 7 and each part 8a, 8b, 8c from the robot control device 2.
iiiQ and the distance f between the TV camera 7 and the lighting device 5
Based on the command value corresponding to
8b and 8c can be illuminated.

The illumination angle control device is formed from a data latch 15, a data conversion circuit 16, and a driver 17. Like the data latch 11 of the illumination light amount control device Retired Emperor, the data latch 15 is connected in advance to each component 8a, 8b, 8c from the TV camera 7 from the robot control device 2.
The command value 2a corresponding to the distance Q between the TV camera 7 and the lighting device 5 and the distance fQ between the TV camera 7 and the lighting device 5 is stored, and when a command value that has changed from the command value 2a is input, it is sent to the data conversion circuit 16. ing. Data conversion circuit 16
is the distance between the TV camera 7 and the lighting device 5 in advance @f
Q and.

Distance m12 between TV camera 7 and parts 8a, 8b, 8c
The relationship between the angle α and the angle α at which the illumination light is illuminated from the lighting device 5 to the parts 8a, 8b, and 8C is calculated using the following formula (1), and α=tan−”2V−. (1) Store this as a data table and use the data clutch 1
Data corresponding to the illumination angle α of the illumination device 5 is sent to the driver 17 based on a command from the illumination device 5. The driver 7 sends a drive signal to the illumination device drive device 6 based on the data from the data conversion circuit 16. Therefore, ± for the illumination angle control device is the distance Q between the TV camera 7 and each component 8a, 8b, 8c from the robot control device 2, and the distance fQ between the TV camera 7 and the lighting device 5.
Based on the command value corresponding to the command value, each component 8a, 8b, 8
It is possible to irradiate C.

Since the illumination device for the image sensor according to the present invention is constructed as described above, the TV camera 7 is attached to the hand 3 of the robot 1 and each part 8a, 8b is attached.

8c, even if the distance #IQ between each part 8a, 8b, 8c to be recognized and the TV camera 7 changes, the illumination is always at the same part position as the input field of view of the TV camera 7. It is possible to illuminate the components 8a, 8b, 8c with constant optimum brightness.

Therefore, flexible recognition processing can be performed without reducing pattern recognition accuracy.

In the above embodiment, a case was described in which the command value from the robot control device 2 is used as the basis, but the invention is not limited to this. For example, a distance sensor may be installed on the hand 3 of the robot 1 and It is also possible to easily control the illumination angle α and the amount of illumination light of the illumination device 5 online.

〔Effect of the invention〕

According to the present invention, by moving a sensor such as a TV camera,
Since the illumination conditions in pattern recognition application systems, where the distance to the target object changes, can always be applied in an optimal manner, it not only improves pattern recognition accuracy but also improves recognition of large objects. Even if the field of view is only for a portion of the object, uniform illumination is not required over the whole area, so the scale of the entire device system can be reduced, which can significantly reduce costs. be able to.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an image sensor illumination device according to an embodiment of the present invention attached to a robot, FIG. 2 is an enlarged explanatory view of the image sensor illumination device shown in FIG. 1, and FIG. FIG. 3 is an enlarged explanatory diagram of the illumination light amount control device and the illumination angle control device shown in FIG. 2; 1...Robot, 2...Robot control device, 3...
- Hands, 4...Base, 5...Lighting device, 6...
Illumination device drive device, 7...TV camera, 8a, 8b
. 8c...Parts, 9...Travel device, 10-...Illumination light amount control 1 mouth

Claims (1)

[Claims] 1. In a method for pattern recognition by electrically converting an object requiring illumination light using a photoelectric sensor, distance data between the photoelectric sensor and the object is detected, and distance data is applied to the distance data. 1. A method for illuminating an image sensor, the method comprising: controlling illumination conditions of illumination light based on the lighting condition of the illumination light. 2. The image according to claim 1, wherein the illumination conditions of the illumination light are controlled by controlling the direction of the illumination light so as to illuminate the same part of the object as the input field of view of the photoelectric sensor. How to illuminate the sensor. 3. The control of the illumination conditions of the illumination light is characterized in that the amount of illumination light is controlled so that the object is always illuminated with constant brightness regardless of the distance between the photoelectric sensor and the object. A method for illuminating an image sensor according to scope 1. 4. In a pattern recognition device that electrically converts an object that requires illumination light using a photoelectric sensor, an illumination mechanism that irradiates the object with the illumination light and distance data between the photoelectric sensor and the object are provided. 1. An illumination device for an image sensor, comprising: a detection mechanism that performs detection; and a control mechanism that controls illumination conditions of the illumination mechanism based on the detection result of distance data by the detection mechanism.