Integrated modeling and robust control for full-envelope flight of robotic helicopters

To accomplish successfully the complex future mission in civilian and military scenarios, robotic helicopters need to have controllers that exploit their full dynamic capabilities. The absence of high-fidelity simulation models has prevented the use of well established multivariable control techniques for the design of high-bandwidth full-flight-envelope control systems. Existing model-based controllers are of low bandwidth and cover only small portions of the vehicle´s flight envelope. In this paper we present the results of the synergistic use of high-fidelity integrated modeling strategies, robust multivariable control techniques, and classical gain scheduling for the rapid and reliable design of high-bandwidth full-flight envelope controllers for robotic helicopters. We implemented and flight tested a gain-scheduled H_∞ loop-shaping controller on the Carnegie Mellon University (CMU) Yamaha R-50 robotic helicopter. During the flight tests, the CMU R-50 flew several high-speed maneuvers. We believe that our modeling/control approach quickly delivers controllers that exploit the full dynamic capabilities of the airframe and thus are ready to be used by higher level navigation systems for complex autonomous missions.