Developed at NASA’s Marshall Space Flight Center (Huntsville, AL), a micro-commanding rotational-position-control system offers the advantage of less mechanical complexity, susceptibility to mechanical resonances, power demand, bulk, weight, and lower cost, relative to prior rotational-position-control systems based on stepping motors and gear drives. This system includes a digital-signal-processor (DSP)-based electronic controller, plus a shaft-angle resolver and a servomotor mounted on the same shaft.

Heretofore, micro-stepping has usually been associated with stepping motors, but in this system, the servomotor is micro-commanded in response to rotational-position feedback from the shaft-angle resolver.

For more information, see page 32 of the March issue of NASA Tech Briefs, or click here .