The video shows the three degree of freedom multi-flexible link robot arm TUDOR (Technische Universität Dortmund omnielastic robot) catch balls thrown by a human. The intrinsic compliance of flexible link robots offers novel opportunities for safe human robot interaction as well as force control. Nevertheless the fast joint motions induce significant structural vibrations and the kinematic chain shows load and configuration dependent static deflections. These properties aggravate the precise positioning of flexible link robots. In the video a stabilizing decentralized strain feedback controller rapidly damps the structural vibrations while an artificial neural network has been trained to solve the inverse kinematics problem for varying configurations and payload. The trajectory of the segmented ball is estimated from measurements obtained via a Microsoft Kinect RGB-D-sensor. The measurements are fused with a motion model including Newton friction via an extended Kalman filter. The camera is mounted next to the laboratory entrance. The demonstrator has a success rate of more than 66%, provided that the ball trajectory intersects the planar subspace of the robot workspace, in which the ball can be caught. Timeline: 00:08 Ball catching without vibration control 00:32 Ball catching with decentralized vibration damping control 01:00 Ball tracking and catch location prediction with the Kinect References: Malzahn, J., A. S. Phung und T. Bertram: A Multi-Link-Flexible Robot Arm Catching Thrown Balls. 7th German Conference on Robotics, 21./22.05.2012 ,pp. 411-416 Mai 2012 For more information on the project please visit: http://www.rst.e-technik.tu-dortmund.... |