Dynamic Analysis and Control Design for a Tiltable Quadrotor

This paper presents a tiltable quadrotor that can independently control position and attitude. Firstly, the dynamic modeling of the system is carried out. We adopted a nonlinear separation strategy for the nonlinear strong input problem existing in the system. We separated the nonlinear system into a linear dynamic link and a nonlinear static link by constructing an intermediate control quantity. Then, linear quadratic regulator with small calculation and easy hardware implementation was designed only for a linear dynamic link while real control, including tilting angle and motor speed, was mapped from intermediate control by calculating the input nonlinear static link. The simulation shows that the designed nonlinear controller based on nonlinear separation and LQR can stably control the tilting quadrotor and can independently track the position and attitude expectations.