Modeling and Control Strategy of a Perching Quadrotor with Payload Retention and Re-flight Functions

To address the trade-off between endurance and payload capacity in unmanned aerial vehicles (UAVs), an energy-saving and mission-extending approach based on perching and re-flight was proposed. A quadrotor UAV equipped with an adhesion mechanism was designed to enable reliable perching on vertical surfaces and payload retention. For dynamics modeling, two distinct dynamic models were developed for the flight and perching states, respectively, revealing the variation in the system's degrees of freedom across phases and the thrust-attitude coupling relationship. Based on these models, a complete control strategy covering target guidance, pressing, stepwise throttle reduction for wall attachment, and re-flight separation was developed to realize a full perching-re-flight closed loop. Experimental results demonstrate that the proposed dynamics models and control strategy effectively support the transition from free flight to wall perching and re-flight, achieving stable attitude control and payload retention. This provides a novel technical solution for long-duration UAV operations in complex urban environments.