Modeling, fabrication, and validation of a high-performance 2-DoF piezoactuator for micromanipulation

A high-performance compact micromanipulation system is presented. The system, called the microgripper microrobot on chip (MMOC), was developed at Laboratoire d'Automatique de Besancon (LAB), France. Two main parts in the MMOC design of the MMOC are discussed: 1) the piezoactuator and 2) the end-effectors. The micromanipulator is partially fabricated in a clean room and the piezoactuator system has been machined using the ultrasonic technique. Tests of micromanipulation have been carried out under both standard laboratory conditions as well as inside a scanning electronic microscope (SEM) chamber. Displacements in the plane and out of the plane are 80 and 200 /spl mu/m, respectively, at 100 V and the MMOC seems to be particularly useful for pick-and-place tasks. Modeling has been performed using the Smits' model and the results confirm the validity of the model for static boundary conditions. The authors have also developed a combined charge and voltage control called Q/V, which results in an order of magnitude reduction in the hysteresis of the piezoactuator. Future work will include integrating force sensors in the micromanipulator in order to measure the manipulation force. This will allow the implementation of the feedback control in the MMOC.