Resources Contact Us Home
Method and apparatus for real-time filtering of a position error signal for a disk drive servo system

Image Number 6 for United States Patent #5995317.

A method and apparatus for real-time filtering of a position error signal in a servo system of a disk drive. Pre-calculated periodic components of the position error signal (PES) are used as future values in a real-time filter, preferably a real-time recursive median filter. This minimizes the amount of time-lag between obtaining the raw PES measurement from the disk surface and the providing the corresponding filtered PES output. This reduced time-lag minimizes the effect on the phase margin (PM) and results in improved servo stability. The invention can be used not only in servo systems in disk drives, but also in servo systems of other mechanical moving storage devices and in servo systems of rotating mechanical machinery in general, where the signal to be filtered may be a position error, velocity error, acceleration error, and the like.

  Recently Added Patents
Method and apparatus for selective decoding in a wireless communication system
Method and apparatus for belling plastic pipe
Sublingual coated tablet of fentanyl
Tricyclic inhibitors of kinases
Use of LPA for encouraging pregnancy, and fertility agent
Pattern identification apparatus, control method and program thereof
Vehicle-mounted camera stabilized passively by vibration isolators
  Randomly Featured Patents
Semiconductor device
Air gun assembly
Can holder
Benzothiophene hydroxamic acid derivatives
Header float system for use with an agricultural windrower or combine
Toner projection system
Method for preventing and treating atherosclerosis
System for a two-stroke crankcase scavenged combustion engine
Connection system for flexible tubing
Grass trimmer wheeled carrier