Signal processing in LVDT for automatic calibration

In this paper, a new automatic calibration method for a displacement sensor is proposed. This new method is proficient of defining the linearity error. The new-fangled measurement scheme contains a stepper motor plunger system with an LVDT. The LVDT is used to regulate the required displacement swing amount in voltages for the motor's linear motion. Using this identified displacement swing amount, displacement sensor's mean sensitivity and the linearity error can be determined. The precision of the projected process depends only on the consistency the calibrated displacement sensor. For doing this calibration, a system in which a stepper motor's rotatory motion is translated into linear motion using the plunger arrangement is proposed. The linear displacement is measured using an LVDT and the data is read through NI DAQ. From this the calibrated table can be prepared by the aid of labVIEW software and simulations are done using MATLAB software; and from this the sensitivity characteristic plot, the linearity characteristics etc. can be prepared.