US Patent 7453622 - Polyelectrolyte gel MEMS pump

http://www.freepatentsonline.com/7453622.html

This patent to Intel teaches a new type of actuation method for micromechanical structures which avoids the necessity of thermal, electrostatic, or piezo actuation mechanisms and which offers simpler and less costly manufacture. Claim 1 reads:

1. A method, comprising:

changing an electrical charge on a cross-linked co-polymer gel network assembly, the polyelectrolyte gel network assembly being coupled to a micro-electromechanical system (MEMS) device; and

moving the micro-electromechanical system (MEMS) device from a first position to a second position in response to changing the charge on the cross-linked co-polymer gel network assembly.