u_A: the aircraft input signal; u_s: the simulator motion input signal; e: pilot sensation error; Fr_I: the inertial reference frame; Fr_S: the simulator reference frame; Fr_PS: the pilot’s head reference frame; R_I: radius vector from the inertial reference frame to the simulator reference frame; R_S: radius vector from the simulator reference frame to the pilot’s head reference frame; x_I, z_I represent the inertial reference frame coordinate directions; x_S, z_S represent the simulator reference frame coordinate directions; x_PS, z_PS represent the pilot’s head reference frame coordinate directions