Experimental approach to calculate the moments of inertia of a hexacopter unmanned aerial vehicle

¹ Center for Robotics and Future Production, Manufacturing, CSIR, Pretoria, South Africa
² Aeronautic Systems, Defence and Security, CSIR, Pretoria, South Africa

^* Corresponding author: tsetati2@csir.co.za

Abstract

Moments of inertia define the amount of torque needed to rotate an object at a defined angular acceleration around a given axis. With the limited information available for multi-rotor unmanned aerial vehicles (UAVs), this paper sets out to experimentally determine the moments of inertia of a hexarotor UAV with a mounted payload. The moments of inertia are calculated in three rotational axes using pendulum and torsion tests. The pendulum test is performed to verify the test setup by experimentally determining a parameter which is already known: gravity. In pitch and yaw orientations gravity could be experimentally calculated to within 1.33% and 1.22% respectively. Unfortunately, this was not the case in the roll orientation, indicating that the test setup in that orientation needs to be adjusted. The torsion test is then performed to determine the period which is used to calculate the moments of inertia. Ultimately, these calculated moments of inertia will be used in simulation from which a flight controller can be designed.