Miniature 70-W Brushless Motor-Controller for Compact Extraterrestrial-Based Actuation

This SBIR will support rover locomotion and manipulation with a system of newly-developed penny-sized 70-W brushless servomotor controllers that are networked on a bus-topology (CANopen DS-402 protocol). Each "P3" controller is small enough to be mounted in the tiny volume normally reserved for the encoder; and, indeed, each P3 carries the entire active electronics of the encoder function by measuring the magnetic field of a 6x2.5-mm radially-polarized button magnet bonded to the tail of the spinning motor shaft. A Kalman filter enables the encoder to read down to 12-bits-absolute at commutated speeds up to 14,000 RPM. The controller has the functions expected of conventional controllers. However, based on three patents of international scope and a fourth PCT application, the part count has been substantially reduced, with subsequent reduced size, fewer sensitivities to radiation, fewer parts that otherwise generate quiescent power, and reduced cost. Phase I demonstrated successful integration with NASA-selected motors and stress-testing of P3 in adverse environments including temperature extremes, vibration, and vacuum, resulting in a TRL-advance from 3 to 4. Phase-II efforts will focus on design-modifications relevant to space-qualification, performance characterization, and further environmental testing including radiation testing. Phase II is expected to result in a TRL of 6. Phase-III commercialization efforts will create a system of motor controllers that not only support NASA rover missions with a TRL of 7, but also support other space-based non-terrestrial applications, such as servomotor actuation on satellites for precision antennae and laser pointing and the deployment of articulated structures.