Active microvalves for micro-fluidic networks in plastics - selecting suitable actuation schemes

Using active microvalves liquid flow in microsystems can be precisely controlled and timed. Plastic microfluidic networks offer high flexibility in the material selection and potentially also allow for low cost mass fabrication. For selecting a suitable micro-actuation scheme, the different options are compared on the basis of actuation performance parameters. For thermal-expansion, electrostatic, electroactive, piezoelectric and shape memory actuation principles the work density is derived from basic actuator physics and literature material parameters. For the targeted actuator dimensions also frequency, stroke and force characteristics are calculated. These are compared with actuator performance targets typical for micro-fluidic networks: forces between 160µN and 16mN, stroke of 50µm, repetition frequencies ranging from 100Hz to few mHz. As a result, only electroactive polymer and thermal actuation principles remain as viable options and shall in further work be experimentally evaluated using a modular design with interchangeable actuators