HIL simulation system for HDD servo firmware

For the purpose of debugging and evaluating quality of the servo-control program used for hard disk drives (HDDs), we have developed a hardware-in-the-loop simulation (HILS) system that uses a computer-based virtual mechanism instead of an actual disk drive mechanism. As the characteristics of the virtual mechanism (e.g., mechanical resonance, disk shift) can be tuned continuously, the capability and tolerance of the servo-control program can be measured quantitatively. In addition, the coded program for a new mechanism can be developed before an actual proto-drive is assembled. We are now applying this HILS system to the development of HDD products.