Abstract
Landing on a moving platform is an essential requirement to achieve high-performance autonomous flight with various vehicles, including quadrotors. We propose an efficient and reliable autonomous landing system, based on model predictive control, which can accurately land in the presence of external disturbances. To detect and track the landing marker, a fast two-stage algorithm is introduced in the gimbaled camera, while a model predictive controller with variable sampling time is used to predict and calculate the entire landing trajectory based on the estimated platform information. As the quadrotor approaches the target platform, the sampling time is gradually shortened to feed a re-planning process that perfects the landing trajectory continuously and rapidly, improving the overall accuracy and computing efficiency. At the same time, a cascade incremental nonlinear dynamic inversion control method is adopted to track the planned trajectory and improve robustness against external disturbances. We carried out both simulations and outdoor flight experiments to demonstrate the effectiveness of the proposed landing system. The results show that the quadrotor can land rapidly and accurately even under external disturbance and that the terminal position, speed and attitude satisfy the requirements of a smooth landing mission.
Highlights
Due to its simple mechanical structure, low cost and relatively high maneuverability, quadrotors are currently of widespread use in multiple commercial and military applications
When the quadrotor power is low or suffers a malfunction that prevents it from reaching a predefined landing area, it is advantageous to be able to land on a mobile platform for recharging or maintenance
When the quadrotor is far away from the moving platform, we identify the vehicle based on a theoretical minimum cost function that works well at a long-distance and with a large-flied-of-view
Summary
Due to its simple mechanical structure, low cost and relatively high maneuverability, quadrotors are currently of widespread use in multiple commercial and military applications. Incremental nonlinear dynamic inversion (INDI) uses the angular acceleration feedback to replace a part of model information with sensor measurements, to reduce the influence of such disturbances and the overall uncertainty of the system [29] This control method was proposed in [30] and has been widely employed in the design of quadrotors control systems [31,32,33]. At the same time, considering the influence of various disturbances in the landing process, a cascade incremental nonlinear dynamic inversion (INDI) control method [33] is adopted to track the planned trajectory and increase robustness. Compared with the previous research on MPC-based trajectory tracking control for quadrotors [16,23,28], the proposed method with variable sampling time reduces the requirements of the onboard computer while ensuring the landing accuracy.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
