Patent ID: 9417633
Filing Date: 2016-08-16
CPC Classification: G01B,G01D,G05B,G05D

Claim Text:
1. A system for compensating dynamic and thermal deformity errors of a linear motion single-plane gantry stage in real time, comprising: a first two-dimensional position measurement unit arranged in each of two linear edge beams respectively positioned on both sides of the linear motion single-plane gantry stage adapted to measure a position of an X-axially movable gantry beam to provide feedback of X-axial motion thereof; a second two-dimensional position measurement unit adapted to measure a position of an Y-axially movable slider that is movable on the X-axially movable gantry beam to provide feedback of an Y-axial motion thereof; a thermal fixing point provided as a thermal reference for measurement of thermal expansion of the X-axially movable gantry beam; and a compensation control unit adapted to control an error motion of the linear motion single-plane gantry stage in real time in accordance with measurement of dynamic and thermal deformity errors based on data received from the first and second two-dimensional position measuring units; wherein the first two-dimensional position measurement unit includes: a first two-dimensional encoder scale mounted on a base below each of both ends of the X-axially movable gantry beam including a two-dimensional lattice adapted to measure both in a motional direction and in a vertical direction; a first motional direction encoder head arranged on a motional direction measurement lattice part of the first two-dimensional encoder scale adapted to measure a motional direction displacement; a first vertical direction encoder head arranged on a vertical direction measurement lattice part of the first two-dimensional encoder scale adapted to measure a vertical direction displacement; and an encoder mounting block adapted to mount the motional direction encoder head and the vertical direction encoder head on the X-axially movable gantry beam.