Various contact systems and methods for manufacturing and using such are disclosed herein. Examples of the contact systems include a surface with one set of pads biased at a first voltage level, and another set of pads biased at a second voltage level. Such a contact system can be used, for example, to transfer power to an electromechanical device disposed thereon. In one particular example, the electromechanical device can include a power storage element and two or more couplings. When one of the couplings contacts a pad biased at the first voltage level, and another of the couplings contacts a pad biased at the second voltage level, a circuit is completed where some derivative of the differential between the first voltage level and the second voltage level is placed across the power storage element. Completion of the circuit causes the power storage element to charge. Power can be drawn from the power storage element to operate the electromechanical device.