The role of piezoceramic microactuation for advanced mobility

This paper presents the potential role of piezoceramic microactuation in micro-robotics for future space missions, e.g. unmanned sample-return missions to Mars, in search of life or evidence of prebiotic materials. The focus of the paper is on the advanced mobility with the desired characteristics of high force, displacement, and operability over a wide temperature range, at the cost of lowest possible mass, volume, and power. A comparison of the various actuation technologies including piezoceramic, shape memory alloys, polymeric actuators and magnetostrictive materials is presented. The comparison suggests piezoceramics to be the most promising candidate. The concept of a flexible microactuator based on tailored films of lead lanthanum zirconate titanate, PLZT, deposited on flexible substrates is described. Such flexible microactuators are expected to offer a multifold enhancement in the force and displacement capabilities over those of the current state-of-the-art actuators based on bulk ceramic materials. Of special interest is the promise of high efficiency actuation from an optimized thin film based flexible bimorph structure by contact-less optical activation.