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Systems Research in the Aerospace Engineering and Mechanics at the University of Minnesota. Gary J. Balas Aerospace Engineering and Mechanics University of Minnesota Minneapolis, MN balas@aem.umn.edu. SAE Aerospace Controls and Guidance Meeting 19 October 2005.
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Systems Research in theAerospace Engineering and Mechanicsat the University of Minnesota Gary J. Balas Aerospace Engineering and Mechanics University of Minnesota Minneapolis, MN balas@aem.umn.edu SAE Aerospace Controls and Guidance Meeting 19 October 2005
University of MinnesotaAerospace Engineering and Mechanics Systems Faculty • William Garrard, Department Head • Modeling, flight control, parachutes • Yiyuan Zhao • Optimization, air traffic control, rotorcraft • Demoz Gebre-Egziabher • Navigation, GPS, sensor fusion • Gary Balas • Robust control, real-time embedded systems, flight control • Bernard Mettler (starts Jan 2006) • Real-time control, planning, rc helicopters and planes
Current Research • “Control Reconfiguration and Fault Detection and Isolation Using Linear, Parameter Varying Techniques,” NASA Langley Research Center, NASA Aviation Safety Program, Dr. Christine Belcastro Technical Monitor • “Stability and Control of Supercavitating Vehicles,” ONR, Dr. Kam Ng Program Manager • Special Session planned for the 2006 American Control Conference entitled “Modeling and Control of High-Speed Underwater Vehicles” • Local Arrangements Chair, 2006 American Control Conference, 14-16 June 2006, Minneapolis, MN
Control of Projectiles Using control thruster firings, the projectile maneuvers to the optimum angle of attack • Tradeoff between many small maneuvers and wider spaced, large maneuvers • Controllability of projectile given a finite number of impulses • Optimal control of a number of thrusters. • Effect of • Burn time • Impulse size and number • Achievable performance
Development of Analysis Tools for Certification of Flight Control Laws - AFOSR Andy Packard (UC Berkeley), Pete Seiler (Honeywell) Initial focus is on nonlinear robustness analysis • Region-of-attraction • Disturbance-to-error gains • Inner and Outer Bounds Connection to MilSpecs
Quantitative Nonlinear Analysis Initial focus • Region of attraction estimation • induced norms • induced norms for • finite-dimensional nonlinear systems, with • polynomial vector fields • parameter uncertainty (also polynomial) Main Tools: • Lyapunov/HJI formulation • Sum-of-squares proofs to ensure nonnegativity • Semidefinite programming (SDP), Bilinear Matrix Inequalities • Optimization interface: YALMIP and SOSTOOLS • SDP solvers: Sedumi • BMIs: using PENBMI (academic license from www.penopt.com)
Estimating Region of Attraction Dynamics, equilibrium point User-defined function whose sub-level sets are to be in region-of-attraction By choice of positive-definite V, maximize so that