Short-span seeking control of hard disk drive based on integral type learning PTC

Abstract

In a short-span seeking-mode of hard disk drives, the two-degree-of-freedom control is generally used. Authors' group proposed the perfect tracking control (PTC) method in order to achieve high accuracy and high speed controlling. We also proposed the learning PTC method which can suppress the overshoot by learning the tracking error in acceleration and deceleration period. In this paper, we propose the developed method named "Integral Type Learning PTC" which can suppress the overshoot higher by integral type learning of the trajectory tracking error.

High precision control of ball screw driven stage using repetitive control with sharp roll-off learning filter

“…RPTC is one of repetitive control which can suppress periodic disturbance by iteration (learning) [5], [8]. In this section, structure of RPTC and convergence condition are explained.…”

“…If there are no modeling errors, this control system guarantees perfect tracking. Moreover, repetitive perfect tracking control (RPTC) which is repetitive control system using multi-rate feedforward controller had been proposed and verified its effectiveness in some industrial devices [6]- [8]. By mathematical analysis, it is verified that RPTC suppresses input and output disturbance and guarantees perfect tracking by only one time learning under ideal condition.…”

Analysis of Filter Designed on the Basis of Short-Span Seeking Control of Hard Disk Drives with Learning-Based PTC

“…Finally, simulations and experiments are performed to confirm the effectiveness of the designed filter. (8) によりフィー ドフォワード制御信号を生成し理想的な制御対象に対して サンプル点上での完全追従を実現した。シーク制御におい て，制御対象を剛体モデルとした剛体 PTC，主共振モードを 積極的に制御する制振 PTC (Vibration Suppression PTC： VSPTC) (9) を，またフォロイング制御において，繰り返し PTC(Repetitive PTC：RPTC) (10) PTC (3) ，LPTC (11) 〈2・1〉 PTC (3) PTC は，Fig.…”

“…〈2・2〉 LPTC (11) LPTC は，ショートスパンシーク制 御において，モデル化誤差により生じた加減速時の追従誤 差を学習し，目標軌道を再設計することにより，理想的な 目標軌道に対する追従特性を改善する手法である。 文献 (11) における，LPTC の構造を Fig. 2 1…”