Smart-Structures Technology for Parallel Robots

Industrial robots play an important role in automation technology. A further increase of productivity is desired, especially in the field of handling and assembly, the domain of industrial robots. Parallel robots demonstrated their potential in applications with needs for high-dynamic trajectories in the recent years. Within the scope of the Collaborative Research Center (SFB 562)-'Robotic Systems for Handling and Assembly' the German Aerospace Center (DLR) and the Technical University of Braunschweig investigate smart-structures technology for parallel robots. In this paper the results of the main topics new active components, Finite-Element based elastic position dependent modeling and vibration control are summarized. The latest parallel robot called is equipped with new active rods. The design as well as the dimensioning of the rod with surface mounted piezo patch actuators is described. For trajectory based robot control, rigid body models are required. In parallel robots with vibration reduction a coupled approach is necessary in which elastic and rigid body equations are combined. The derivation of the equations for parallel robot is presented. Finally, the implemented vibration control is explained. In a position-dependent approach several robust controllers are switched to gain optimal control performance. A stability proof for the switching process is derived.