Improvements of the calibration of the electronic level and by a new multiple reflections technique-based setup

Dimensional measuring machines in the National Metrology Institute require accurate levelling on a surface plate during installation for the optimal performance. Nowadays, the commercially available electronic inclinometers having an accuracy and precision of the order of a micro-radian serve the purpose. Therefore, their calibration became essential. This work attempted to establish authentic practices to calibrate electronic levels using various measuring instruments. Different experiments are performed using a reference autocollimator, an angle measuring laser interferometer, and a novel setup. Various errors involved in each of the calibration system are explored. The results obtained in the experiments are mathematically modelled. Then, their associated uncertainty of the measurement is calculated.

A new measurement algorithm is devised to improve the results by reducing errors due to misalignment. A novel experimental setup is developed by implementing the multiple reflection technique for the calibration of the electronic level. The calibration results of the electronic level are improved by 20 % by the novel setup.