The structure light vision method research most early appears in the 20th century 70's. In many visual methods, the structure light three dimensional vision by its great measuring range, the big field of view, compares the high accuracy, the light strip picture information is easy to withdraw, timeliness is strong and is controlled on own initiative and so on the characteristic, in recent years obtained the widespread application in the industry three dimensional survey domain.

2nd, system design principle, block diagram, schematic diagram

The structure light three dimensional vision is based on optics 三角�?the survey principle. Like the chart shows, optics projector (may be a laser, also may be projecting apparatus) the certain pattern structure light projection to the object surface, forms in the surface by was measured the object surface shape modulates light strip three dimensional picture. This three dimensional picture by is in another position the camera to absorb, thus obtains the light strip two-dimensional distortion picture. The light strip distortion degree is decided by is decided between optics projector and the camera relative position and the object table face shape gallery (highly). On direct-viewing, demonstrated along the light strip the displacement (or displacement) highly becomes the proportion with the object, 扭结 expressed the plane change, has not continuously demonstrated the superficial physical gap. When between optics projector and the camera relative position is certain, then may reappear the object surface three dimensional shape gallery by the distortion two-dimensional light strip picture coordinates. The structure light three dimensional vision measurement system by optics projector, the camera, and the computer system three parts constitutes.

1. backgrounds photosources 2. 标定�?. skid the guide rail 4. work tables 5. CCD pickup camera 6. Projecting apparatus (LCD) 7. main engines 8. monitors

The light beam pattern difference projects which according to optics projector, the structure light pattern may divide into 点结�?the light pattern, 线结�?the light pattern, many 线结�?light pattern and the cellular texture light pattern. 线结�?light pattern complex low, information content big, the application is most widespread. The next chart hits for 线结�?the light in 标定板and is measured the object the light strip picture.

3rd, shaping principle, precision analysis

Structure light vision sensor measuring accuracy many factors influences, like camera itself optics physics parameter, optics projector characteristic parameter, sensor itself design parameter and outside noise source and so on. In the camera, in the optics projection survey environment certain situation, the measurement system design parameter is very big to the measuring accuracy influence. Experimental and the correlation theory inferential reasoning indicated, measuring point position error and system structure relevance as follows:

When 1) camera optical axis and light plane vertical, the depth direction measuring error is smallest.

2) camera and optics projector distance farther, the measuring error is smaller.

3) the camera lens enlarges the percentage slightly, the measuring error is smaller; This surface was also measured the object leaves the camera farther measuring error to be bigger.

When after system geometry structure determination, the camera parameter is very important to the system measuring accuracy. By 行扫�?the CCD camera dynamirange big, the noise is small, does not have the odd and even line 场频 to meet the error, extremely suits the survey the application. Camera resolution higher, dynamirange bigger, the survey precision is higher. A typical measurement system is: Uses Lasiris laser projector which Danish JAI Corporation million picture elements levels the CV-A1 camera, Japanese Computar Corporation's 16 mm focal distance lens, Canadian StockerYale Corporation produces. Concrete product parameter as follows:

L CV-A1 camera: 1/2 "target surface, 1380*1035 picture element, by 行扫�? 帧� 16fps, analog output, sensitivity 0.3Lux

L M1614-MP lens: C connection, focal distance 16mm, F several 1.4

L PC2-Vision picture gathering card: Canadian CORECO Corporation produces the simulation gathering card, may simultaneously meet 6 black and white cameras or 2 RGB colored camera.

4th, application prospect

Industry scene three dimensional survey, airplane contour, water wheel leaf blade shape, automobile contour, missile, satellite, large-scale radar geometry size survey, archaeology scene, traffic accident scene, athlete path track, machine manpower movement axle