Design and Construction of an Electronic Tiltmeter Calibrator and Estimation of Calibration Uncertainty

Electronic tiltmeter is used as a tool of setting the accurate angles in advanced equipment. The accuracy and precision of tiltmeter should be evaluated by means of precise calibration equipment. This study aimed to calibrate and evaluate the accuracy of a precise dual axis electronic tiltmeter. To this end, a calibration setup with accurate positioning capability was designed and constructed. Then the calibration setup was employed to investigate linear and nonlinear behavior of electronic tiltmeter and extract the corresponding equations. In order to assess the reliability of the tiltmeter sensor, nonlinearity error and repeatability of the tiltmeter at different angles were obtained. Afterwards in an analytic way, arithmetic and geometric means were compared and the factors which affect the calibrator output error were identified to obtain that how much the accuracy and measurement error of each of those factors affect the uncertainty of angle measurement in the calibration process. The results indicate that both introduced methods of averaging can be used to derive relationship of uncertainty propagation accurately. Uncertainty analysis of the constructed base and calibration process demonstrate that the employed equipment correspond with the evaluation of a precise electronic tiltmeter.