Dr. Art Wagner
Consultant

Abstract

In computer systems, an important data storage medium, beginning in the 1950s until today, is the Hard Disk Drive (HDD). Using magnetic heads, the HDD reads and writes data on magnetic surfaces of spinning disks. A disk drive actuator positions the magnetic heads on data using a combination of position and velocity feedback control. An engineer configures an actuator from magnets, steel, a coil, bearings, and head arms. The presentation centers on the progression of actuator configurations. The talk pays attention to parameters important for control, such as the force factor or torque factor, mass or inertia, and coil resistance. In this presentation, we discuss configuration evolution from typical early actuators to configurations prevalent in today’s actuators and control. We answer the question, what has changed, what is the same?

Biography

Dr. Art Wagner has designed in the areas of the magnetics and control of the actuator and the spindle motor for a multitude of disk drive companies, including Seagate, Maxtor, Maxoptics, Quantum, Conner Peripherals, IBM, ISS, Priam, Iota, StorCard, and Swan.

Art taught full time at SJSU for 13 years attaining full professorship with tenure, then he went into the disk drive industry. He designed in the areas of the magnetics and control of the actuator and the spindle motor for a multitude of disk drive companies, including Seagate, Maxtor, Maxoptics, Quantum, Conner Peripherals, IBM, ISS, Priam, Iota, StorCard, and Swan. Along the way, Art taught a series of short courses on the moving coil actuator, the disk drive spindle motor, and perpendicular magnetic recording. He also taught classes part-time at Santa Clara University on mechatronics. Presently, he is teaching a class at SJSU. Art received a bachelor’s degree from Santa Clara University, master’s degree from the University of Arizona, and a Ph.D. from Oregon State University.

He is a member of the SCV Magnetics Society and a regular attendee at our meetings.

• Dr. Art Wagner
• wagneretal [at] sbcglobal [dot] net