Zephyr: A High Altitude Long Endurance Unmanned Air Vehicle ...

The magnetic sensor seemed much more feasible as it did not have any delicate parts(figure 12). The magnetic sensor uses the Hall Effect by having a vane attached to onemagnet and as it is moved by the wind it causes the magnet to move and thus the HallVoltage to change. Although this had clear advantages as it did not have any criticalparts that had to be in contact (unlike the potentiometer), it was not compatible withthe electronics onboard Zephyr. It was decided that although a magnetic sensor was agood idea in the long run, it was not feasible to change the electronics on the aircraftat the present time.Figure 12. Diagram to show the magnetic sensor. The wind vane would be attached tothe brown magnet which would be placed inside the silver pod [12]Other magnetic sensors were investigated, but they were all too big and too heavy forZephyr. A sensor has to be small so it can be placed on the aircraft without affectingthe aerodynamics, and light not to add significant weight onto Zephyr.There was another possible solution which involved using the original sensor butheating it in order to keep it within its certified temperatures. It was decided however48