Stereo vision algorithm for robotic assembly operations

A stereo vision Linear Triangulation (LT) algorithm can be utilized in space robotics assembly operations. The LT algorithm recovers the relative orientation and translation (pose) of objects marked with high contrast targets using two or more pinhole charge-coupled device (CCD) cameras. The cameras view a set (including a disjoint set) of targets measured with respect to the same point in space. This study evaluates the theoretical accuracy of the LT algorithm, its benefits and performance. The introduction of a third camera into the vision system envelope is also examined and discussed. Experiments indicated that most accuracy in pose estimation is gained by the first 15-25 degrees of camera separation, and then the decrease in values of the covariance matrix elements stabilizes. We compare the numerical data for singe, two-camera and threecamera cases using extensive experiments on simulated images.