Patent ID: 6084398
Filing Date: 2000-07-04
Classification: G01P,H02P

Abstract:
A system for measuring rate of rotation, comprising:a brushless DC motor having a shaft driven to rotation and having windings disposed about said shaft wherein, when said shaft rotates, a back electromagnetic force (emf) is produced on each of said windings, said back-emf including information on rate of rotation of said shaft;a plurality of integrators, each of said plurality of integrators coupled to a corresponding one of said windings for integrating said back-emf associated therewith to produce an integrated output;a plurality of multipliers, each of said plurality of multipliers coupled to one of said windings to receive said back-emf associated therewith and coupled to one of said plurality of integrators to receive said integrated output associated with another of said windings adjacent said one of said windings, wherein each of said plurality of multipliers produces a multiplied output; anda combining circuit coupled to said plurality of multipliers for combining each said multiplied output to produce a DC output proportional only to said rate of rotation of said shaft.