Stick and slip actuators and parallel architectures dedicated to microrobotics

Stick and slip actuators are particularly well adapted to microrobotics. A simple design, a very high intrinsic resolution (a few nanometers) and a high rigidity makes them specially interesting for high precision micro manipulations. Moreover, a smart design allows to combine the guiding and actuating functions. Parallel architectures are attractive to microrobotics too. They present a high rigidity and the actuators are fixed on the base. This paper will deal with the integration of stick and slip actuators in a 6-degrees-of-freedom parallel structure dedicated to the micro assembly of optical components. In section 3 we describe and characterise inertial actuators using the stick and slip effect. We demonstrate their performances (velocity higher than 1.5 mm/s, 10 nm precision) and limits. In section 4 we describe the 6-degrees-of-freedom parallel architecture that we developed for our application and how the actuators are integrated into it. Its kinematics, the joins' forces and the working volume have been calculated. A resolution better than 30 nm is possible within a working volume of 140 mm(3). Orientations of several degrees (up to +/- 5 degrees) are possible for the three rotational angles.