Control design oriented modeling of an on-ground aircraft

A simple and efficient control allocation scheme for on-ground aircraft runway centerline tracking

“…To go one step further and take into account the constraints set out in Section 2, a 3 degree-of-freedom (DOF) model was recently introduced in [18]. Both the longitudinal and lateral aerodynamic effects and the tireground interactions are included, as well as simple dependencies on the vertical load and the runway state.…”

“…An intensive validation process revealed that this model is usually very accurate, except when the anti-skid system is active, in which case the proposed pseudo-decoupling of the ground forces is arguable. To address this issue, this paper improves the work of [18] by introducing a better model of the coupled longitudinal and lateral ground forces, at the price of a very reasonable increase in complexity.…”

A detailed comparison of control allocation techniques on a realistic on-ground aircraft benchmark

“…1. It is based on the aircraft model described in [1]. In practice, a dynamic inversion based high level controller computes a virtual input v =ṙ actc corresponding to the commanded yaw acceleration to be produced by the actuators.…”

“…and R e denote the number of tires, the longitudinal friction fraction [1], the normal load and the main landing gear wheel rolling radius respectively. In the same way as before, F z M G is obtained by a moment balance at the nose landing gear around the lateral axis of the aircraft:…”

“…[8], [3]), to apply them to the aforementioned allocation problem, and to perform a thorough comparison on a realistic worst-case scenario. Using an accurate yet tractable on-ground aircraft model developed in [1], the proposed benchmark takes into account all existing actuators (rudder, NWS system and brakes), including their dynamics and limitations. It also considers changes in the actuators efficiencies due to the variations of normal load and aircraft velocity during the roll-out phase.…”