Algorithm for local nonlinear error calibration of displacement sensor based on C2 continuous interpolation

The laser displacement sensor based on the triangulation method has the advantages of large range, high precision, and strong anti-interference. Due to the limitation of the measurement principle, although the laser displacement sensor has high repeated measurement accuracy, it has serious high-order nonlinear system errors. Considering that in some measurement occasions, only a few local measurement intervals within the range are used. In this paper, a local nonlinear error calibration algorithm based on C2 continuous interpolation was proposed. A nonlinear calibration model was established by intensive calibration data acquisition in the local interval of the measurement application. The model can be smoothly connected with the original linear calibration model. At the same time, the measurement accuracy of the local area is greatly improved without affecting the accuracy of other intervals.