Calibration Methods for an Aerolab 375 Sting Balance to be used in Wind Tunnel Testing

The attached Thesis and undergraduate research are submitted to satisfy the Transcript Notation requirements for the Department of Physics.Internal force, or sting, balances are used in wind tunnel testing to measure the total force and moment imposed on an aerodynamic structure. A sting balance operates through strain gauges converting strain from externally applied loads to voltage signals. An accurate measuring device is of paramount importance in wind tunnel testing, and this thesis concerns itself with calibrating such measurement device for use with micro air vehicles in a wind tunnel. A calibration matrix was found to convert the voltage output of the balance to force and moment data. Known loads were applied to the different channels of the sting balance and a custom made program was used to read and post process the voltages produced by the strain gauges in the balance under load. A relationship between voltage and load was then found and used to produce the calibration matrix. The calibration matrix was then inputted into a different program to test the accuracy and resolution of the balance by applying known loads, as a reference, and comparing the measured forces to the reference