Modelling and simulation of wirelessly and securely interrogated low-powered actuators for bio-MEMS

This paper presents modelling and analysis of microactuators that are designed for implantable bio-MEMS applications. Microactuators are considered to be a major component of microvalves and micropumps. A novel interrogation methodology is implemented, which is based on surface acoustic wave (SAW) devices and wireless transcutaneous RF communication. This unique combination of technologies results in a novel microactuator that can be remotely and securely interrogated by an RF system, with the advantage of no power requirements at the actuator site. ANSYS based finite element analysis (FEA) is performed to model the microactuator, and a Rayleigh-Ritz method based analytical model is developed to investigate the validity of FEA results. During FEA, a 3D model of the microactuator is developed, and a coupled-field analysis is carried out to model the electrostatic-solid interaction between the microactuator and the SAW device. Consequently, detailed 3D modelling and transient results are presented, and the low-powered microdisplacements at low frequencies are clearly demonstrated.