長ストロークと高精度位置決めを両立する連係微動（連続ステップ位置決めへの適用）

概要

論文の詳細を見る
Cooperative positioning is a positioning technique in which long stroke paths and ultraprecision positioning are combined. These are achieved simultaneously in a single apparatus using extended displacement positioning (EDP) and reduced displacement positioning (RDP), respectively. In the present study, we developed a new control program for a 2-stage hinged cooperative positioning device. RDP is first carried out by a series of step motions of the fine positioning stage. The extended displacement stage is then moved using EDP by an amount equal to the total displacement achieved by RDP. Simultaneously, the fine positioning stage is returned to its initial position using RDP. Continuous step positioning then becomes possible by repeating these operations. The maximum stroke was 67.1 μm and a settling range of less than the EDP displacement resolution (27 nm) was achieved. Some positioning errors were found to occur due to switching between the two types of operation. However, these could be reduced by increasing the EDP control coefficient to improve synchronization, or by decreasing the number of positioning steps. In this way, the amount of overshoot and the settling time could be effectively controlled. Using this apparatus, it was shown that continuous positioning with 25 nm steps was possible.