Improved antishock air-gap control algorithm with acceleration feedforward control for high-numerical aperture near-field storage system using solid immersion lens

Jung Gon Kim, Won Ho Shin, Hyun Woo Hwang, Jun Jeong, Kyoung Su Park, No Cheol Park, Hyunseok Yang, Young Pil Park, Jin Moo Park, Do Hyeon Son, Jeong Kyo Seo, In Ho Choi

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

A near-field storage system using a solid immersion lens (SIL) has been studied as a high-density optical disc drive system. The major goal of this research is to improve the robustness of the air-gap controller for a SIL-based near-field recording (NFR) system against dynamic disturbances, such as external shocks. The servo system is essential in near-field (NF) technology because the nanogap distance between the SIL and the disc is 50nm or less. Also, the air-gap distance must be maintained without collision between the SIL and the disc to detect a stable gap error and read-out signals when an external shock is applied. Therefore, we propose an improved air-gap control algorithm using only an acceleration feedforward controller (AFC) to maintain the air-gap distance without contact for a 4.48 G at 10 ms shock. Thus, the antishock control performance for the SIL-based NF storage system in the presence of external shocks is markedly improved. Furthermore, to enhance the performance of the antishock air-gap control, we use the AFC with a double disturbance observer and a dead-zone nonlinear controller. As a result, the air-gap distance is maintained without contact for a 6.56 G@10ms shock.

Original languageEnglish
Article number08KC06
JournalJapanese journal of applied physics
Volume49
Issue number8 PART 3
DOIs
Publication statusPublished - 2010 Aug

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Improved antishock air-gap control algorithm with acceleration feedforward control for high-numerical aperture near-field storage system using solid immersion lens'. Together they form a unique fingerprint.

Cite this