Special surface for power delivery to wireless micro-electro-mechanical systems

This paper reports a special surface suitable to distribute power while providing a high-precision surface where wireless micro-electro-mechanical systems must operate. The surface is made of alternate electrically conducting and narrower insulating bands with dimensions that allow power to be delivered to the wireless systems when in contact with at least two electrically conductive bands. In this study, a first implementation using stainless steel 440C and black granite is analyzed in more detail. The dimensions of both the conducting and insulating bands are described by considering the properties of the materials used and the precision of the micro-mechanical systems that may be affected by features on the surface with dimensions down to the nanometer scale. The effects on the dimensions of the bands due to the total mass of each microsystem, the contact surface area between the microsystems and the powering surface, and the accuracy of the positioning system used, are also taken into account. Minimum widths of the insulating bands and the methods to prevent electrical shorts between a pair of successive bands, created through arcing between the conductive bands and a conductive structure of the wireless units when stationary or transiting through an insulating band, are also evaluated and compared when operating in air or helium atmosphere.