Complex motion design and control of aircraft model suspended with cable-driven parallel robot at high AoAs

Modern advanced fighters are characterized by the post-stall maneuverability with multi-degree-of-freedom (M-DOF) at high angles of attack (AoAs), which is generally difficult to simulate with the traditional sting suspension method in wind tunnel due to its limited M-DOF capability and dynamics. This paper studies the complex motion control of an aircraft model suspended with a novel cable-driven parallel robot (CDPR) to reappear some typical agile maneuvers with high AOAs and large amplitudes. The tasks include modeling the unsteady aerodynamics, designing the desired motion command, and developing the robust control law. Firstly, the kinematic and dynamic equations of CDPR are given, and the state-space representation of aerodynamic forces and moments for unsteady aircraft motion is established. Subsequently, an angular motion involving rolling around the velocity vector is proposed, and a typical M-DOF motion trajectory is also designed. To deal with modeling uncertainties and external disturbances, a robust feedback controller is constructed by integrating the computed-torque control law with extended state observer (ESO), and its stability is analyzed using the Lyapunov function. ADAMS simulations and numerical investigations conducted on the CDPR validate the effectiveness of the proposed methods and controller.