KR101360028B1 - Measuring device for 6 dof motion based on laser sensor through optimaization design - Google Patents

Abstract

According to the present invention, a laser sensor-based device for measuring a 6 degree of freedom motion comprises: three laser sensors for entering laser into an object; an image processing device for calculating a 2-dimensional coordinate of a phase by image-processing the phase focused on the object when the laser emitted from the laser sensors is entered; and a main control part for calculating a 6 degree of freedom motion of the object by receiving the 2-dimensional coordinate from the image processing device and distance information from the laser sensors. At least three laser sensors are arranged not in parallel with each other. The installation height difference, the distance separated from each other, and the rotational installation angle of the at least three laser sensors are decided by an optimized method.

Description

Measuring device for 6 DOF Motion Based on Laser Sensor Through Optimaization Design}

The present invention relates to a laser sensor based six degree of freedom motion measurement device through an optimized design.

An example of a device for measuring 6 degrees of freedom motion of a moving object is disclosed in Korean Patent Application Publication No. 10-2001-0103297, published on November 23, 2001. However, this conventional technique measures 6 degrees of freedom of a target object by using a pattern of reflected light by emitting a laser to a three-sided reflector. This technique can measure six degrees of freedom motion at short distances, but measures six degrees of freedom motion at long distances There is a drawback that it is not appropriate to

An object of the present invention is to provide a laser sensor-based 6 degrees of freedom motion measuring device that can measure the 6 degrees of freedom motion of a target object precisely and at high speed even over a long distance.

According to the present invention, a laser sensor-based measuring apparatus for measuring six degrees of freedom motion includes (1) at least three laser sensors for injecting a laser into the object, and (2) a laser emitted from the laser sensor is used for the object. An image processing apparatus that calculates two-dimensional coordinates of the image by image-processing an image formed by entering an object, and (3) receiving the two-dimensional coordinates from the image processing apparatus and receiving distance information from the laser sensor It includes a main control unit for calculating the six degrees of freedom motion of the target object.

The at least three laser sensors are arranged to be non-parallel with respect to each other, and the installation height difference, the distance from each other and the rotation installation angle of the at least three laser sensors are determined by an optimization method.

According to a preferred aspect of the present invention, the apparatus further includes an angle sensor provided to the target object, and the image processing apparatus further receives angle information from the angle sensor and transfers the angle information to the main controller.

The optimization method may be a genetic algorithm or a least square method.

According to another aspect of the present invention, the apparatus further includes a laser pointer for injecting a laser into the target object, and the image processing apparatus further processes the image of the laser pointer incident on the target object to perform image processing to perform two-dimensional image processing. Calculate the coordinates.

According to the present invention, in the six degrees of freedom measurement, the measurement error is reduced, and six degrees of freedom can be measured effectively even at a long distance.

1 is a conceptual diagram for explaining a measuring principle of a laser measuring apparatus according to the present invention.
2 is a diagram showing an example of the arrangement of the laser measuring apparatus according to the present invention;
3 is a view for explaining the image formed by the laser sensor according to the present invention incident on the target object.
4 is a block diagram of a laser sensor based measurement apparatus according to the present invention.
5 shows exemplary simulation results of the optimization method according to the invention.
6 is a view for explaining another embodiment of the present invention.

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

,

,

로 구성된다.FIG. 1 is a diagram illustrating an image and a basic principle of the laser of the laser sensors 10, 20, and 30 formed on the object 50. 1 shows a case in which the laser sensors 10, 20, 30 are arranged in parallel with each other for simplicity of explanation. When the laser sensor 10, 20, 30 shoots the laser on the target object 50, an image similar to the red dot of FIG. 1 is formed. Likewise, three-dimensional coordinates can be given to each phase. The six degrees of freedom displacement of the target object 50 include three angle values with respect to three axes, that is, roll angle (θ; roll angle), pitch angle (φ; pitch), yaw angle (ψ; yaw), and three Displacement about axis

,

,

.

2 shows a laser sensor arrangement in accordance with the present invention. According to the present invention, three or more laser sensors are arranged in a non-parallel relationship without being arranged in parallel with each other. The difference in installation heights, distances and rotational installation angles between the respective laser sensors is determined by an optimization method. . As an optimization method, a genetic algorithm or a least square method may be used.

In the present specification, the laser sensor means a one-dimensional laser sensor.

3 shows an exemplary placement conceptual diagram of the laser sensors 10, 20, 30. The first laser sensor 10 and the second laser sensor 20 are provided to the support 50 at the same height, and the third laser sensor 30 is disposed with a height difference H therebetween. It is assumed that the distances from the third laser sensor 30 to the first laser sensor 10 and the second laser sensor 20 are equal to L, respectively. Each of the laser sensors 10, 20, and 30 are disposed not parallel to each other. The rotation angle about the X axis is defined as α and the order of the laser sensors is indicated by subscripts, so that the rotation angle about the X axis of the corresponding laser sensor is shown. Is displayed. The rotation angle about the Y axis is defined as β and the order of the laser sensors is indicated by subscripts to indicate the rotation angle about the Y axis of the laser sensor.

If the coordinate system is defined as shown in FIG. 3, the positions of the first to third laser sensors viewed in the laser sensor structure may be defined as follows.

로 정의하면,

Lt; / RTI >

는 i번째 레이저 센서에서 측정한 대상물체까지의 거리를 의미한다.

Denotes the distance to the object measured by the i-th laser sensor.

As a result, the overall equation for calculating six degrees of freedom can be derived as follows.

,

,

)는 i번째 레이저 센서에 의해서 대상 물체에 맺힌 상을 카메라(40)가 촬영하여 영상처리함으로써 측정된 각각의 상(像)의 좌표를 의미한다. 그리고

는 i번째 레이저 센서의 센서 노이즈값을 의미하며, e는 구조적 설계 오차를 의미한다. 구조적 설계 오차는 레이저 장치를 설치할 때 발생하게 되는 오차를 의미하며, 설계적 오류와 탭 틈새 등에 의해서 발생한다.From here (

,

,

) Denotes the coordinates of each image measured by the camera 40 photographing an image formed on the object by the i-th laser sensor. And

Denotes a sensor noise value of the i-th laser sensor, and e denotes a structural design error. Structural design error refers to an error that occurs when installing a laser device, and is caused by a design error and a tab gap.

및

를 산출할 수 있게 된다.Using the above equation, cost fuction J is an optimization design that minimizes the root mean square of measurement error. For example, the structural variables L, H, which are structural variables using a genetic algorithm or a least square method, etc. ,

And

Can be calculated.

5 shows an exemplary result of simulating an error in the angle measurement using a genetic algorithm. Referring to the simulation result, the distance between the laser sensors and the twisted angle that can minimize the error can be determined. have.

In the present specification, a case of three laser sensors will be described, and it can be easily understood by applying the technical spirit of the present invention to the number more than that.

Figure 4 is a block diagram of a laser sensor based 6 degrees of freedom motion measuring apparatus according to the present invention. As shown in FIG. 4, the measuring device according to the present invention includes a main controller 100, at least three laser sensors 200, an image processor 300, a camera 320, and a laser sensor motor. A portion 400 is included. The angle sensor 340 is not an essential component of the measuring device according to the present invention.

The image information of the spot formed by the laser light shot by the laser sensor 200 on the object 50 is processed by the image processor 300 through the camera 320, and the laser sensor 200 measures the main control part 300. ), The three-dimensional coordinate information (x, y, z) of the spot is calculated based on the distance information.

The three-dimensional coordinate information thus calculated is wirelessly transmitted to the main control unit 100, and the main control unit 100 calculates six degrees of freedom motion based on the above-described relational expression. Meanwhile, when an angle sensor 340 such as a tilt sensor or a gyro sensor is provided on the target object 50, measurement accuracy may be further increased by using a sensor fusion algorithm.

  The laser sensor motor control unit 400 controls the motor mounted on the laser sensor 200 to control the motor so that the laser that the laser sensor 200 shoots on the target object 50 does not miss.

In another embodiment of the present invention, an embodiment of adding a laser pointer having a function of shooting a laser light to a target object without a distance measuring function, to a measuring device composed of laser sensors 10, 20, and 30 It demonstrates. As used herein, the term "laser pointer" means a device having a function of forming a spot by injecting a laser beam into a target object, and means a device that does not include a distance measuring function.

6 shows a conceptual diagram of an embodiment in which laser pointers 60, 70 are added. For the sake of simplicity, the arrangement of the laser sensors 10, 20, 30 and the laser pointers 60, 70 are arranged to be spaced apart from each other by the same distance from the center while forming a polygon as shown in FIG. It is assumed that the laser sensors 10, 20, 30 and the laser pointers 60, 70 are arranged in parallel with each other. If the radius of the array is r, the k th laser sensor and the i th laser pointer have the following relation.

From here

The six degrees of freedom motion of the target object 50 can be calculated by increasing the redundancy of the equation by the above-described relationship. The above relation may vary depending on the arrangement of the laser sensors 10, 20, 30 and the laser pointers 60, 70, and it should be understood that this is an exemplary relation.

Although there is no distance measuring function as described above, a measurement error may be reduced by increasing redundancy by using a laser pointer capable of shooting a laser onto the target object 50.

While the preferred embodiments of the present invention have been described with reference to the accompanying drawings, it is to be understood that the scope of the present invention is defined by the appended claims rather than by the foregoing description and drawings. And that improvements, changes and / or modifications, obvious to those skilled in the art, of the invention described in the claims are also included within the scope of the present invention.

10, 20, 30: laser sensor
50: object
100: subject fisherman
200: laser sensor
300: image processor
320: angle sensor
340: camera

Claims (4)

In the laser sensor-based measuring device for measuring the six degrees of freedom motion of the target object,
At least three laser sensors for injecting a laser beam into the object;
An image processing apparatus which calculates two-dimensional coordinates of the image by image-processing an image formed by the laser emitted from the laser sensor incident on the object;
A main control unit which receives the two-dimensional coordinates from the image processing apparatus and receives distance information from the laser sensor to calculate six degrees of freedom motion of the target object;
The at least three laser sensors are arranged to be non-parallel to each other,
The installation height difference, the distance from each other and the rotation installation angle of the at least three laser sensors are determined by an optimization method,
6 degrees of freedom measuring device based on laser sensor.
The method according to claim 1,
Further comprising an angle sensor provided to the target object,
The image processing apparatus further receives angle information from the angle sensor and transmits the angle information to the main controller.
6 degrees of freedom measuring device based on laser sensor.
The method according to claim 1 or 2,
The optimization method is a genetic algorithm or a least square method,
6 degrees of freedom measuring device based on laser sensor.
The method according to claim 1 or 2,
Further comprising a laser pointer for injecting a laser into the target object,
The image processing apparatus also calculates two-dimensional coordinates of the image by processing an image that the laser pointer enters and forms on the object.
6 degrees of freedom measuring device based on laser sensor.

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