Adaptive Artificial Time Delay Control for Quadrotors under State-dependent Unknown Dynamics

Swati Dantu1    Rishabh Dev Yadav1    Spandan Roy1    Jinoh Lee2    Simone Baldi3   

1 IIIT Hyderabad, India    2 Institute of Robotics and Mechatronics, German Aerospace Center (DLR)    3 School of Mathematics and School of CyberScience and Engineering, Southeast University, Nanjing, China   

Quadrotors are becoming more and more essential for applications such as payload delivery, inspection and search-and-rescue. Such operations pose considerable control challenges, especially when various (a priori unbounded) statedependent unknown dynamics arises from payload variations, aerodynamic effects and from reaction forces while operating close to the ground or in a confined space. However, existing adaptive control strategies for quadrotors cannot handle unknown state-dependent uncertainties. We address such unsolved control challenge in this work via a novel adaptive method for artificial time delay control, where unknown dynamics is robustly compensated by using input and state measurements collected at immediate past time instant (i.e., artificially delayed). Closed-loop stability is established via Lyapunov theory. The effectiveness of this controller is validated using experimental results.