Temperature Compensation of Laser Triangular Displacement Sensor

The measurement precision of the laser triangulation displacement sensor will be decreased with temperature, its application areas have been restricted for a long time. Three main factors affecting measurement accuracy were analyzed and two algorithms were proposed in this paper to compensate for the temperature error. Experiments of the three aspects such as measurement distance, chip temperature and ambient temperature are shown. In addition, a temperature compensation model based on multiple linear regression was proposed. Considering that various influencing factors are not simple coupling, a neural network technology that can effectively solve nonlinear problems was used and a three-layer neural network model was also built, which can generate temperature compensation values. At the same time, the results of the two algorithms were compared. Results show that the neural network model reduces the displacement temperature drift from the original -80μm ~+50μm to within ±20μm in the range of 0~40°C, which significantly improves the temperature adaptability of the laser displacement sensor and is successfully applied in the aerospace field.