The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 25, 1978
Filed:
Jun. 14, 1977
William John Case, Winchester, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
Positioning and motion control of two objects, for example, of a transducer and a disk record medium having tracks including pre-recorded servo information, is achieved in two modes of operation in the following manner: During a track following mode the transducer is connected in a closed servo loop and position error signals derived by the transducer are used to energize an actuator mechanism coupled to the transducer so as to maintain the transducer in the on-track position. During a track seek mode, the actuator is energized to cause the transducer to follow a desired velocity profile, at least a part of which is achieved with the transducer connected in a closed servo loop. The loop is fed with position error signals derived by the transducer sampled at times calculated to coincide with the on-track positions of a transducer following the desired velocity profile. The servo system responds as in track following mode to energize the actuator mechanism so as to reduce the instantaneous transducer position error from the true on-track positions during this part of the access operation with the overall effect of causing the transducer to follow the desired velocity profile more closely.