Disc head arm position controller using digital velocity sensing

Abstract From the Canadian patent

Electronic circuitry for improving the speed and accuracy of shifting the magnetic heads of a disk memory from one to another track cylinder. Head velocity is measured with great accuracy by measuring the servo head transit time between adjacent tracks of the servo disk. A microprocessor controller in conjunction with preferred velocity profile data stored in a read only memory provides a control signal to the linear motor control causing the head arm velocity to follow the preferred velocity profile with excellent precision.