Dynamic Testing of Brushless DC Motors for SAE Aero

                For the 6th year in a row Union college will be competing in the SAE Aero competition.  At the moment the regular class and micro class competitions both use electric motors as the propulsion systems of the RC plane. Brushless DC motors are typically the type of motor used to fly these RC planes. Unlike Brushed DC motors, Brushless DC motors do not have the same current-to-torque relationship which makes calculating torque very difficult. Torque measurements cannot be taken while in flight and without torque measurements the mechanical efficiency of the motor cannot be found; however if a relationship could be derived between torque and other known information- like speed or thrust for example- motor efficiency can be found. The goal of my project is use a system to determine motor efficiency without having to find the actual torque of the motor. This system will be invaluable for current and future teams due to its many forms of data collection. The current test setup uses a RC Benchmark dynamometer that allows for a wide array of testing simulations along with the large data acquisition. Being able to dynamically test a motor and gather physical data is better than using motor data sheets for plane design. Currently the advanced class uses a gas motor but due to future rule changes the competition will move to electric motors in the near future due to past rule changes made in the micro and regular classes.