Simulation and experimental evaluation of laser-structured actuators for a mobile microrobot

This paper describes the simulation, fabrication and evaluation of a mobile platform´s actuator, which is the foundation for microrobots. The working principle is based on the mobile platform RollBot. The new feature is the combination of three rolling steel spheres driven by three laser structured piezoactuators, each containing three ruby hemispheres. Because of the piezoactuator´s special design, the hemisphere´s stick-slip displacements decrease and enable a more precise control. The platform´s properties concerning rigidity, resolution and maximum velocity improve. After an introduction of RollBot´s and the new actuation principle, a short description of the laser structuring process is given. Several finite-element (FE)-simulations are presented to understand the expected performance of the mobile platform. Finally, measurements of step sizes and maximum velocities are shown. The application of the actuator in a mobile platform proves the derived properties.