Error analysis and self-correction of an inductive linear displacement sensor

Error analysis on a PCB based inductive linear displacement sensor is introduced in this paper, and a self-correcting method independent of external reference for the sensor is proposed in this paper. This method is mainly aimed at the linear displacement error of short period caused by manufacturing and assembly of sensor prototype. In this paper, only the 1-order, 2-order and 4-order errors common in the measurement process are studied. Therefore, studying from the output signal, the generation mechanism of three kinds of errors has been traced theoretically, and the functional relationship between the output signal and error has been calculated, thus establishing the short-period error function model of the relevant sensor signal. In the experimental verification stage, four comparative tests were carried out, which effectively verified the feasibility of the self-correcting method. The results of prototype experiments show that the measurement accuracy of the sensor prototype has been effectively improved. The 1-order error is reduced by about 64.5%, the 2-order error is reduced by about 3.8%, the 4-order error is reduced by about 83%, and the total error is reduced from 51.6μm to 36.2μm.