Control of MEMS Microactuators for Bio-inspired Microbotic Applications

Professor Kenn R. Oldham

Department of Mechanical Engineering

University of Michigan

Abstract

Autonomous robots at the millimeter- and centimeter-scale have potential to provide unique robotic capabilities in a number of applications, but are a huge challenge for system design, fabrication, and control. As MEMS technology advances, an increasing number of microactuator applications will incorporate feedback control, but most existing devices are components in much larger systems, where power usage at the MEMS device is not critical to overall system performance. In contrast, autonomous micro-robots require control strategies that limit power consumption throughout the robot, including sensor and interface power as well as power to the microactuators themselves.

Novel piezoelectric actuators can provide low-power, high-force actuation capable of generating bio-inspired, insect-like motion of terrestrial micro-robots. These actuators are currently being integrated with high-aspect silicon microstructures to produce functional leg joints with satisfactory load-bearing capabilities.

Unfortunately, traditional controllers for piezoelectric actuation consume much more energy in amplification and circuitry than at the actuators themselves. Several alternative control schemes are proposed, based on continuous, on-off, and open-loop techniques, and compared with regards to actuation, interface, and sensing power. Future research goals to refine these controllers and expand their use to other applications are discussed.

Friday, September 28, 2007

3:30 – 4:30 p.m.

Rm. 1500 EECS