Hybrid Controller for Improved Position Control of Quadrotors in Urban Wind Conditions

Abstract

A hybrid control technique combining both proportional derivative (PD) and adaptive integral backstepping (AIB) control strategies is proposed for position control within a building-generated wind wake. Position hold performance for a quadrotor (, ) within windfields obtained from large-eddy simulations are used to compare control strategies. Simulated results show that both the PD and AIB control approaches can outperform each other depending on position within the wake. Over multiple positions within a wake, simulations show the hybrid approach reduces the average volume within which the vehicle remains by approximately 50% over both an exclusively PD or AIB control approach. Simulations also show the hybrid approach can hold the quadrotor to within an average of approximately one body length of the desired position compared to one to two body lengths using a PD control and two body lengths using an AIB control. Flight tests performed using PD and hybrid approaches confirm the improved position hold ability of the hybrid controller in building wake environments. Flight data show the hybrid controller reduces the average volume within which the vehicle remains bounded by approximately 50% compared to the volume obtained using the PD controller.