Damaged Drone System Identification
The aim of this research project is to fundamentally improve the safety of drones by developing a new safe envelope predictive (SENCE) flight control system. The goal of the SENCE controller will be to prevent loss-of-control after failures, and allow the drone to conduct a controlled landing, or complete a critical mission such as search and rescue. SENCE will complement existing autopilot or artificial intelligence systems, and will add a new layer of safety to any system it is applied to.
SENCE is not only fault tolerant to system failures, but is also capable of using predictions of the remaining maneuvering envelope and acting intelligently on this information. A new insight has been that using stochastic formulations of Hamilton-Jacobi (HJ) type partial differential equations, we can obtain a probabilistic interpretation of the maneuvering envelope resulting in a ‘landscape’ of safety levels. This in turn will allow for a much more precise balancing of safety and performance to meet specific mission needs.
In order to reach this aim and develop the FENCE controller, new stochastic formulations of the stochastic HJ equations will be researched. After this, research will be done to determine the stochastic maneuvering envelopes of damaged drones based on flight test data. To obtain this data, flight test experiments with damaged drones are conducted in the CyberZoo motion capturing facility operated by the Delft Robotics Institute and in the TU-Delft Open Jet wind tunnel Facility (OJF). This project will be conducted in collaboration with the TU-Delft MAVlab which is a world leader in the field of small autonomous drones.
Recently, we have been able to demonstrate loss-of-control with a damaged drone. In this case, the one rotor of the drone was reduced to 25% of its original area, after which flight tests were conducted in the OJF. While the Adaptive INDI fault tolerant controller is able to maintain position of the drone at 2m/s forward velocity, an aggressive altitude maneuver causes the drone to lose control and crash.