RESEARCH ON HIGH-PRECISION TIME-GRATING DISPLACEMENT SENSOR

Peng Donglin  Liu Xiaokang  Zhang Xinghong  Chen Xihou

(Department of Electronic Engineering, Chongqing Institute of Technology, Chongqing 400050)

Abstract: The advantage and disadvantage of traditional displacement sensors are analyzed. The time space transformation idea, the time space transformation method and the principle of time grating sensor are discussed. By researching the high precision time grating displacement sensor, the principle, structure, resolution and accuracy of the single tooth type, frequency difference type, field type and composite type time grating are introduced. The time grating displacement sensor that has passed through the appraisal gets a 0.1″resolution and ±0.8″accuracy. Meanwhile a harmonic wave correcting idea is introduced. Besides the error decomposing and analysis of sensor, FFT is used to design parameter and correct error before and during the sensor is made. The technical advantages of time grating as a smart sensor and practical effect of harmonic wave correcting are obvious. The purpose is to realize high-precision measurement without the requirement of high precision machining and high precision scale ruler.

Key words: Correcting  Precision  Time grating  Displacement sensor

CLC No: TB22

国家自然科学基金资助项目(59675089，50075091). Received 20050302, received in revised form 20050810