Analysis and compensation of synchronous measurement error for multi-channel laser interferometer

Abstract

Dual-frequency laser interferometer has been widely used in precision motion system as a displacement sensor, to achieve nanoscale positioning or synchronization accuracy. In a multi-channel laser interferometer synchronous measurement system, signal delays are different in the different channels, which will cause asynchronous measurement, and then lead to measurement error, synchronous measurement error (SME). Based on signal delay analysis of the measurement system, this paper presents a multi-channel SME framework for synchronous measurement, and establishes the model between SME and motion velocity. Further, a real-time compensation method for SME is proposed. This method has been verified in a self-developed laser interferometer signal processing board (SPB). The experiment result showed that, using this compensation method, at a motion velocity 0.89 m s−1, the max SME between two measuring channels in the SPB is 1.1 nm. This method is more easily implemented and applied to engineering than the method of directly testing smaller signal delay.

Comprehensive analysis of the influence of structural and dynamic parameters on the accuracy of nano-precision positioning stages

“…Multi-axis plane mirror interferometers are often used in nano-precision positioning stages [28][29][30][31][32]36]. The measurement model of a multi-axis interferometer can be composed of multiple models of single-axis interferometers.…”

“…Liu et al [27] established an error model of an H-type ultra-precision positioning stage that considers error factors, such as straightness, thermal deformation, structural deformation, and variations in air bearing gaps to evaluate measurement uncertainty. Gao et al [28][29][30] analyzed the influence of the geometric and installation errors of interferometers and reflectors on measurement results by using a simplified model of the measurement beam path of interferometers; they designed a novel six-degree-of-freedom (6-DOF) measurement method for an ultra-precision motion platform and optimized the geometric tolerance allocation. Teng et al [31] and Wen et al [32] established an interferometer measurement model that considers the orientation errors of reflector mirrors to compensate the result errors of the measurement system of the ultraprecision motion platform.…”

Pulse Compression Shape-Based ADC/DAC Chain Synchronization Measurement Algorithm with Sub-Sampling Resolution

“…The synchronization issues between channels in the aforementioned multi-channel systems have been the subjects of extensive attention from both the academic and industrial communities [12][13][14]. Moreover, the synchronization performance of signal sampling and data transmission across different channels has a significant impact on the reliability of the system.…”

A flexible self-calibration method for large-stroke motion stage by using the multi-region stitching strategy based on least square algorithm

“…When the systematic error of the measuring object is obtained accurately, the positional accuracy can be made more accurate by compensating the systematic error of the measuring object. At present, the laser interferometer measurement system (LIMS) is widely used, [3][4][5] but it is easy to be influenced by external environmental factors, such as temperature, pressure, humidity, etc., [6][7][8] which is often difficult to achieve high precision and stable calibration. Thus, the traditional calibration method has been unable to adapt to the calibration of high PMS.…”