Research On Obtaining Range Image Using Multi-Line Structured Light And Image Processing

With the continuous development of science technology and the eagerness of mankind to know the world, traditional machine vision cannot meet the requirement of 3D object recognition. Range image carries 3D feature information of object, namely range information. Range image isn't influenced by the shinning direction of light source and reflection characteristic of the surface of object, so shade doesn't exist and therefore the 3D range information of the surface of object can be expressed more accurately. Obtaining range image with the technology of structured light is deeply researched in recent days. Researching multi-line structured light technology is a completely new trend. The technology of obtaining range image by the multi-line structured light is simple. The amount of image needed is small while the procession speed is high. Besides the structure of the entire device is simple, and the device can be manufactured easily. Structured light stripe designed by computer can improve the space resolution in the view field of target; and it can obtain the range data of each point of target accurately. The range image can reflect the outline and geometric feature of the target accurately. The structured light stripe can even meet the different requirement of resolution. This paper introduces the range-image-obtaining principle with multi-line structured light and the mathematical model of 3D measurement by using the stripe color to determine the symbol stripe of multi-line structured light. And, as well, this paper designs the parameters of the entire device and calibrates the projector and the image sensor. The theory and experiment research of pretreatment and edge detection are performed aiming at range image. Range image is obtained by use of the multi-line structured light range image obtaining device. The experiment results show that: the speed of obtaining range image using multi-line structured light technology is high; range image processing technology can detect the outline and angle point of target effectively and can determine the angle point whether is concave or protruding; the edge detected is more accurate and the geometric feature of the edge of the target detected is more reliable. This technology can be used in image analysis and recognition technology of 3D target.