High Assurance Control

High assurance control strategies allow systems to operate robustly under a large range of varying conditions such as changing mass, actuator loss or malfunction, and changing environmnetal conditions like intermittent gusts of wind. Our work in high assurance control focuses on nonlinear Adaptive Robust Control (ARC), which as the name suggests is both adaptive (the system automatically responds to changes in parameters such as mass) and robust (the system maintains performance over a wide range of paramater and disturbance values). Such a control scheme eliminates the need for hand-tuning of PID controllers, and instead the ARC automatically determines appropriate values.

Our lab's work in this area has developed a novel nonlinear ARC, using as an example system a quadcopter delivering a package in an urban environment. The nonlinear ARC's abilities are demonstrated in two ways. First, the system automatically responds to the changing mass of the aircraft when the package is dropped. Second, the system is able to robustly operate when strong gusts of wind are present, such as those that would be common when flying near large buildings in an urban setting. This work also utilizes our unmanned systems testbed for rapid verification of the algorithms involved.