Control of a robotic manipulator to grasp a moving target using vision

Consideration is given to grasping a moving target by adaptively controlling a robot manipulator. The adaptive controller is capable to compensate for the system modeling errors and unknown payloads without deterioration of its performance. Because of the time needed to extract information from the computer images, a time delay is inherent in the calculated position of the object. This can be circumvented by predicting the position of the object so that the end effector of the manipulator can grasp it. Since the dynamics of the object are assumed to be unknown, a prediction is performed based on an autoregressive (AR) model, which is determined using the information extracted from the computer images. The information is then utilized in the controller so that the manipulator will grasp the moving object. The details of the prediction scheme are given. Control of the manipulator is reviewed. A simulation study on a manipulator for grasping a moving target using vision information and a self-tuning controller is described. The practicality of the approach is demonstrated by the laboratory experiments presented