Electrostatic actuator with fault tolerant electrode structure
A high-power electrostatic actuator comprising rotor and stator layers with fault-tolerant electrode structures, a housing to contain the electrodes and dielectric fluid, and electronic circuitry driving a plurality of high-voltage phases. The actuator is constructed from multiple rotor and stator films separated by spacing elements. The electrode structure provides self-alignment for precise assembly. The actuator assembly includes built-in fine-position sensors to allow optimal timing in powering phases, and a coarse position sensor for feedback control. The electrode structure has a large region of linear force to provide low torque-ripple allowing simple high/low voltage pulsing instead of analog high voltage waveforms. Single or double sided flexible circuit manufacturing techniques are used to fabricate the rotor and stator films at low cost.
1. An electrostatic actuator, comprising:
one or more rotor layers each formed from a flexible circuit and all of which connected to a single, substantially steady voltage level; and a plurality of stator layers, each having electrodes connected to a plurality of high voltage phases, wherein distinct groups of radially extending electrodes of the stator layers are arranged in concentric rings separated by gaps, with each ring being driven by a different one of the high voltage phases and wherein the plurality of stator layers are interconnected by inserting a pin through a slit cut in a high resistance connection of each layer.