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A low cost, robust, self-priming and bubble tolerance pneumatically actuated planar micro-pump was demonstrated and characterized. This micro-pump has a simple three-layered structure. The two micro-pump housings were fabricated with polycarbonate, while the actuation membrane which, also acted as the inlet and outlet valves was made form polydimethylsiloxane(PDMS). PDMS displayed desirable mechanical properties including very low Young's modulus, high elongation, biocompatibility and good sealing for the design of this micropump. The use of PDMS as actuation memberanes solved problems of sealing and poor compression ratio associated with most silicon based micro-pumps. Furthermore, polycarbonate material is much easier and cheaper to fabricate than silicon wafer. Using external compressed air and vacuum source for atuation, flow rate near to 1000ul/min of air or liquid has been achieved. The maximum pump head of more than 2m is obtained with water as pumping media. The pump exhibited a linear output flow rate, insensitive to output pressure.

This paper studies the characteristics of a micro-beam interacting with an incompressible fluid in a fluid chamber with an opening in its bottom face for fluid flow. The Euler–Bernoulli equation for transverse deformation of an elastic beam is coupled with the fundamental hydrodynamic equation, which is solved by Galerkin and separation of variables method. The 2D fluid flow assumption in Cartesian coordinate has been used. Natural frequencies and mode shapes of wet beam are calculated and compared with the dry beam. The effects of geometrical parameter changes are also computed as a benchmark for the design of the micro-pump. It is observed that fluid coupling causes a decrease for beam’s natural frequencies, especially in higher modes. Furthermore, since the results of the dry and wet beam show a small discrepancy in lower modes, the mode related to the dry beam was employed as the trial function in the forced vibration analysis of the coupled system.

A new fuzzy method was proposed used as micro-pump controller of water-position driver with the uncertainty math model. Takagi–Sugeno fuzzy if-then ruler numbers are adaptive with the control requirements and data space. The ruler is identified by the input position difference and difference rate, and the output of controller is the driving voltage of micro-pump. A recursive kalman filtering algorithm is presented in order to avoid the difficulty of the inverse matrix calculation. The simulation of step plus test demonstrated the stated method is effective and can meet the dynamic control requirement.