Design and Testing of a Mesoscale Piezoelectric Inchworm Actuator with Microridges

Design and testing of a mesoscale actuator device is presented in this paper. The device uses frequency rectification concepts to amplify the displacements while retaining comparable force outputs to current piezoelectric actuators. The design is based on an inchworm motor with the exception that microridges are used in the clamping system. A FEM model is used to design a device that produces a peak to peak amplitude of 900 N at 11 mm/sec with a weight of 100 g (i.e., specific power of 99 W/kg). Experimental data for piezoelectric stacks and adhesives are used in the design analysis. A prototype device is fabricated and tested with excellent agreement between analysis and testing results. Stress and modal analysis are used to demonstrate that the device has an infinite fatigue life and a first modal frequency at 1777 Hz.