Air Force Research Laboratory, Air Vehicles Directorate
Principal Investigator and Technical Lead
3 February 2017 – 3 May 2018
Total award $85,389
The development of control architectures for hypersonic vehicles presents a significant challenge due to widely varying flight conditions in which these vehicles operate and certain aspects unique to hypersonic flight. One particular safety and operational concern in hypersonic flight is inlet unstart, which not only produce a significant decrease in the thrust but also can lead to loss of control and possibly the loss of the vehicle. One potential flight condition that can cause an inlet unstart is flying at a large angle-of-attack or sideslip angle. In Phase I, a nonlinear dynamic inversion (NDI) adaptive controller was developed with the ability to enforce state constraints in order to restrict the vehicle from approaching these large aerodynamic angles. In addition, due to the challenges associated with equipping hypersonic vehicles with traditional external sensor equipment, an observer-based feedback controller for the longitudinal axis of a generic hypersonic vehicle was developed.
Phase II will investigate a single control framework that consists of an observer-based feedback controller capable of achieving tracking for a full 6 degree-of-freedom hypersonic vehicle model, and an NDI adaptive controller capable of enforcing state constraints without full-state measurements. Additionally, a sampled-data NDI control framework is being developed to not only achieve tracking but also include enforcing state constraints as well. The effect of slower sampling times on the ability to control the aircraft and enforce state constraints will be investigated.
- Develop theory for an observer based feedback controller capable of tracking commands that account for the full coupling dynamics, i.e. along both the longitudinal and lateral/directional axes of the aircraft.
- Develop theory for enforcing state constraints in the observer-feedback adaptive dynamic inversion architecture.
- Develop, implement and analyze a sampled-data control framework based on the continuous time controller previously developed.
Working with me on this program are Research Assistants:
- Douglas Famularo, Ph.D student
- Sean Whitney, B.S. student