Flight Control for a Tilt-Rotor Quadcopter with Linear Servo Motors

This paper presents the design and flight control system of a novel tilt-rotor quadcopter that employs two linear servo motors for tilting mechanisms. Each linear servo motor connects to two rotors on the same side of the fuselage via linkages. This configuration reduces the number of servos but introduces additional control constraints and complicates the control allocation process. To address this issue, an iterative control allocation algorithm is proposed. Initially, a set of tilt angles is specified, followed by the calculation of corresponding motor thrusts. The motor thrusts are then used to update the tilt angles iteratively, thereby converging towards the desired tilt angles and thrusts. Simulations encompassing attitude response, pose decoupling, and trajectory tracking demonstrate and validate the effectiveness of the proposed control strategy.