Applicability of MEMS cantilever micro-dilatometer for direct transverse strain monitoring in electroactive polymers

摘要

The paper presents construction and performance of cantilever micro-dilatometer designed to directly monitor transverse strain in electroactive polymer (EAP) specimens actuated by high voltage (HV) stimuli. The displacement is detected by MEMS cantilever microsensor fitted with insulating stylus positioned directly on the specimen surface. The apparatus may be operated in direct as well as synchronous mode making measurements possible of quasi-static as well as dynamic micro-displacements excited by dc and ac HV stimuli with kHz bandwidth. Sensitivity of the test method in direct mode of operation approaches 200 nm while the synchronous mode provides considerable performance enhancement by over an order of magnitude. The upper range of measurements reaches over 100 μm making the apparatus applicable in testing of extensive variety of electronic EAP materials.