Hand-Eye Coordination Using Active Stereo Camera
Wei‐Yun Yau, Han Wang, D.P. Mital · 1996
This paper describes an approach to control the robot arm using active stereo camera system. The proposed handeye system is able to achieve high accuracy without drastically reducing the workspace size. A new qualitative ap proach to control the robot arm is developed. It computes the relative depth between two points from a pair of stereo image. By incorporating this attribute into the image space, a pseudo three-dimensional (3D) image space is obtained. Subsequently, the pseudo image space is used to compute the required transformation from the image space to the robot space. Such an approach does not require the recovery of the intrinsic and extrinsic parameters of the stereo vision system or the 3D coordinates of the target object. Therefore, it is robust to changes in the parameters of the vision system and thus allows the integration of active vision system. A method to cater for focal length changes for achieving variable resolution is also described. Experiments are conducted to verify the accuracy and performance of the proposed method. stage, the vision system can fixate at the object to be manipulated and increase its resolution without losing sight of the object. 2 Qualitative Approach Hand-eye coordination does not require the precise quantitative recovery of the 3D world coordinates to carry out most of its tasks successfully. Qualitative and relative information will suffice, even for accurate positioning. The advantage of such an approach is that it is robust to changes in the visual parameters, thus allowing the integration of active vision system. The most crucial problem of hand-eye 1