Wing-Flap Angle measurement

Abstract

This project is based around the need of calculating the angle difference between a wing and its movable flap in laboratory conditions. In this case there was already an existing wing without such capacity but with a movable flap, and thus it was chosen to serve as a model. Originally this wing had a servo that moved the flap up and down and the angle data was extrapolated from the output of the servo. Under test conditions however the servo couldn't move the flap against the wind, and the measure of the angle was lost. It was chosen then due to various constraints (size, placement,...) that a choice of electronic sensors would be advisable, all controlled by a PLC capable of feeding a final angular difference to the laboratory software. Three sensors were selected for the project: accelerometers/gyroscopes, an infrared sensor, and a hall effect sensor, with the hope that a combination of them may provide the best result for test conditions with high wind speeds and vibrations. The wing was elongated and fixed, and the sensors were programmed and calibrated. The conclusion was reached however that the hall effect sensor and the laser sensor would be difficult to implement since they were impossible to calibrate with precision. As such a pair of gyroscopes and accelerometers was placed on a wind tunnel to test if the results would be gravely affected by the air turbulence and vibrations. Luckily, while the accelerometers suffered under the test conditions, the gyroscopes had no significant changes or deviations with respect to their measures at rest, as such they were considered the best solution.