Three-dimensional vision for robot manipulator control
Peter Shuttleworth, Max Robinson · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1990
For a number of years Nottingham Polytechnic has been investigating the use of stereoscopic vision in robotic applications. The aim of the current project is to produce a robotic system which can locate an object in three dimensional space, move the arm to the correct position and then pick up the object without human intervention. The technique uses a pair of television cameras configured to give a stereoscopic view of the working envelope of the robot manipulator. A prototype vision guided robot manipulator control system has been produced. The system uses photogrammetric calibration procedures which can account for unknown camera position and/or orientation as well as the major components of lens distortion. The calibration mechanism also performs the eye- hand-coordination function. This prototype uses a stereoscopic camera arrangement to provide three dimensional position information. The stereo-correspondence problem is solved using a combination of structured light and dedicated electronic hardware. The result of the work is a prototype manipulator control system which uses vision to close the control loop. The overall effect is a robot arm which moves towards an object, correcting its position as it moves. This is similar in concept to the way human beings approach the problem of grasping an object.