Long stroke displacement measurement with reduced coupling error supporting high precision control of a beam flexure-based micro-stage

Abstract

This paper presents a novel beam flexure-based X–Y–θ micro-stage integrated with a laser interferometric type displacement measurement approach for reducing the measurement error induced by the rotational motion and cross-axis load effect. Aiming at achieving high-precision real-time control of the proposed system, an active disturbance rejection controller is developed such that the inevitable parasitic and coupling errors can be treated as disturbances and actively compensated by using the extended state observer. Finally, the verification experiments are deployed on the fabricated prototype, where the results indicate that the proposed approach achieves excellent performance in terms of motion accuracy and disturbance rejections.

Design and Testing of a Novel Nested, Compliant, Constant-Force Mechanism with Millimeter-Scale Strokes

“…With the rapid development of precision engineering fields, micro/nano manipulation technology is gradually developing in the direction of miniaturization and integration [ 1 , 2 , 3 , 4 ]. The emergence of compliant mechanisms is successfully and widely used in the field of micro/nano manipulation.…”

A Fiber-Based Chromatic Dispersion Probe for Simultaneous Measurement of X-Axis and Z-Axis Displacements with Nanometric Resolutions

“…To address the issue of the displacement measurement of the micro-stage and fulfill the development of the application of the displacement measurement in the space-limited and small-cavity fields, many displacement measurement sensors and techniques [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ] have been proposed so far, such as optical interferometers [ 11 , 12 , 13 ], digital image correlation sensors [ 14 , 15 ], thin film displacement sensors [ 16 , 17 ], integrated capacitive displacement sensors [ 18 , 19 ], hall-effect sensors [ 20 ], and so on. For the optical interferometers, not only the miniature laser diode interferometer [ 11 ], the compact laser interferometer based on the displacement sensing method [ 12 ], but also the Fabry–Pérot interferometer [ 13 ] can achieve good measurement resolutions with large-stroke measurement ranges. However, due to the large-stroke optical path, these optical interferometers are relatively fragile and sensitive to the environmental disturbances of temperature, humidity, pressure, as well as air turbulence, which will change the air refractive index beyond that it is complicated to be mounted [ 21 , 22 ].…”

“…Based on the macro-bending effect, optical fiber-based sensors have been constructed for the displacement measurement of the dual-axis of the measured micro-stage [ 29 , 32 ]. However, in the above fiber-based sensors, most of the sensors can only measure one axis displacement, and extra optical components are necessary if more than one axis needs to be measured, which will lead to more errors introduced to the sensors and the complexity of the overall systems [ 12 , 33 ]. As for the optical fiber-based sensors based on the macro-bending effect, these sensors have shown good sensitivity and stability, but because of the core-cladding modal coupling, the detected spectral signals will experience wavelength-dependent losses [ 34 ].…”