On Modeling and Control of a Holonomic Tricopter

Most holonomic Unmanned Aerial Vehicles (HUAVs) (usually small-scale), employ at least four high-power thrusting actuators, resulting in increased mass, inertia, and energy consumption. In this work, a novel design for a HUAV using only three high-power thrusting actuators is developed. The pointing dynamics of the high rpm motor-propeller assemblies are included in the analysis, resulting in the exposure of oscillatory gyroscopic dynamics. These are studied analytically to yield vectoring oscillation frequency estimates, useful in selecting actuators. A geometric, singularity free, control framework comprised of a new control-allocation scheme and a new vectoring controller is developed. Stability proofs are included and controller robustness is addressed. Simulations (MATLAB/GAZEBO) demonstrating the effectiveness of the developed design and control framework are provided; a HUAV with independent position/attitude regulation (full pose control) using only three thrusting actuators is showcased.