Abstract: A system and method for controlling energization of an electric motor (rotating or linear). The system and method includes producing a pulse-width modulated command signal to control switching devices that connect the motor to an energization source. A pulse-width modulated duty cycle value is formed as a function of the pulse-width modulated command signal. A leading current with respect to the phase angle of the back EMF is provided to the motor as a function comparing the pulse-width modulated duty cycle value with a selected threshold.

Abstract: This invention is a method and apparatus for automatically adjusting the command signal of a servomechanism, to improve the accuracy of control over the motion of an object. In one embodiment, the command signal is advanced in time, to compensate for the delayed response of the servo. The time advance is repeatedly and automatically adjusted so as to minimize the magnitude of the tracking error. Each adjustment of the time advance is based on the value of a sampled error signal, taken at selected points in time. Other parameters of the command signal, such as the amplitude and average level, can also be adjusted, and the adjustments for all parameters can be done simultaneously. For a given parameter, the error signal is sampled at those points at which misadjustment of that parameter is most likely to contribute to the error of the system. Thus, in general, different parameters of the command signal are adjusted based on different sets of sampled points of the signal.

Abstract: A circuit is disclosed for controlling the position or velocity of a moving object. The motion of the object may be linear or rotational. The object is moved by an electric motor, or linear actuator, which is driven by a power amplifier. The current output of the amplifier, which drives the motor or linear actuator, is controlled by an input signal based at least in part on the estimated velocity of the object. The control circuit includes a pair of integrators connected in series, the inputs to the integrators being dependent both on the current output from the amplifier, and on the difference between the output of the second integrator and the actual sensed position of the object. The velocity estimation circuit is thus based on a form of Kalman filter. The velocity estimator uses a model of the motor which is extremely simple, and which contains only constants. The velocity estimator can control the motor very accurately without detailed knowledge of the model of the motor.