Abstract: A comprehensive dynamic model of X-type quadrotor was established and simulated. Different from other widely used models that usually treated quadrotor as a single-rigid-body system, the rotors, propellers and the aircraft body were treated as a multi-rigid-body system in the proposed model. The 3D model wireframe was constructed using Solidworks and the important inertial parameters were extracted from the design data. Two types of multi-channel-double-loop vector PD flight controller were designed and fine tuned, one was based on quaternion feedback and the other was based on Euler angle feedback. The close-loop systems were simulated on Matlab/Simulink. The simulation results show that both systems achieve stable control of aircraft position and pose, however, quaternion feedback based controller shows shorter transition time, less computation and no singularity point compared to Euler angle feedback based controller.

Key words: X-type quadrotor, multi-rigid-body system, quaternion, PD