Microfabrication of integrated FMAS using stereo lithography

The flexible microactuator (FMA) is a novel pneumatic rubber actuator developed for use in microrobots. This paper reports on its miniaturization and integration using a stereo lithography method, also known as a photo-forming. First, two key technical issues arising in the application of stereo lithography to FMA fabrication are discussed. One issue is the development of a new FFIA design, which we call a "restraint beam" FMA. This design makes it possible to fabricate FMAs from a single material, allowing lithography to be used. The other issue is related to materials. While conventional materials used in stereo lithography are rigid plastics, new investigations of rubber-like materials are necessary. In this report, we show experimentally that appropriate compound coloring of a resin enables us to control its side-forming and elastic properties. Later in the paper, several examples of fabrication and experiments on prototype FMAs are reported; we discuss the fabrication equipment, the bending motions of "restraint beam" FMAs, the integration of pneumatic circuits, and a 5/spl times/5 FMA array. The 5/spl times/5 array was successfully able to move a glass plate placed on it.