Fully adaptive velocity tracking drive control positioning system

Abstract

An infinitely adaptive motor control positioning system is disclosed which uses a calculated variable velocity curve while tracking deceleration and acceleration before and after application of a power pulse so as to anticipate movement for continuing adjustable power cycles. This enables the system to optimize positioning accuracy and minimize elapsed time positioning a driven mechanism. Up to seven phases of drive occur in any positioning move. Each phase consists of drive cycles when the motor receives power (and thus accelerates) and then is void of power (and thus decelerates). During each drive cycle, different sets of equations are implemented to calculate an 'ideal speed' based upon the system response, actual speed, previously used power, and the distance still required to reach the target. The appropriate power computing equation is selected from a set of equations based upon a combination of factors: comparison of actual speed to 'ideal' speed; pattern of speed change during the previous cycles; previous powers used; the velocity error; proximity to a phase transition; and the general trend of the mechanism response. The final target approach uses current position, speed, and deceleration to project the stopping point if no more power is supplied. Then a new velocity curve is calculated in reference to the target position and remaining distance to evaluate how the next power cycle should be controlled. Initially, power is applied in varying degrees to obtain broad information on the acceleration and deceleration characteristics of the driven mechanism. With this data, the power is adjusted to control the speed so that the driven mechanism can eventually coast to a stop within the defined settling tolerance of the target.