FUNDING ($K) TRANSITIONS “Stability region analysis using sum-of-squares programming,”

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FUNDING ($K) TRANSITIONS “Stability region analysis using sum-of-squares programming,” 2006 American Control Conference, pp. 2297- 2302. “Local gain analysis of nonlinear systems,” 2006 American Control Conference, pp. 92-96 STUDENTS, POST-DOCS Ufuk Topcu, Tim Wheeler, Weehong Tan LABORATORY POINT OF CONTACT Development of Analysis Tools for Certification of Flight Control Laws UC Berkeley, Andrew Packard, Honeywell, Pete Seiler, U Minnesota, Gary Balas APPROACH/TECHNICAL CHALLENGES Analysis based on Lyapunov/storage fcn method Non-convex sum-of-squares (SOS) optimization Merge info from conventional simulation-based assessment methods to aid in the nonconvex opt Unfavorable growth in computation: state order, vector field degree and # of uncertainties. Reliance on SDP and BMI solvers, which remain under development, unstable and unreliable Long-Term PAYOFF Direct model-based analysis of nonlinear systems OBJECTIVES Develop robustness analysis tools applicable to certification of flight control laws: quantitative analysis of locally stable, uncertain systems Complement simulation with Lyapunov- based proof techniques, actively using simulation Connect Lyapunov-type questions to MilSpec-type measures of robustness and performance Region-of-attraction Disturbance-to-error gain Verify set containments in state-space with SOS proof certificates. V 1 p 2 p 3 p x 0 f dx dV 1 V x . FY04 FY05 FY06 FY07 FY08 AFOSR Funds 97 141 Other 0 0 Aid nonconvex proof search (Lyapunov fcn coeffs) with constraints from simulation Convex outer bound

description

Development of Analysis Tools for Certification of Flight Control Laws UC Berkeley, Andrew Packard, Honeywell, Pete Seiler, U Minnesota, Gary Balas. Region-of-attraction Disturbance-to-error gain Verify set containments in state-space with SOS proof certificates. Long-Term PAYOFF - PowerPoint PPT Presentation

Transcript of FUNDING ($K) TRANSITIONS “Stability region analysis using sum-of-squares programming,”

Page 1: FUNDING ($K) TRANSITIONS “Stability region analysis using sum-of-squares programming,”

FUNDING ($K)

TRANSITIONS“Stability region analysis using sum-of-squares programming,”2006 American Control Conference, pp. 2297-2302.“Local gain analysis of nonlinear systems,” 2006 American Control Conference, pp. 92-96STUDENTS, POST-DOCSUfuk Topcu, Tim Wheeler, Weehong Tan

LABORATORY POINT OF CONTACT Dr. Siva Banda, Dr. David Doman

Development of Analysis Tools for Certification of Flight Control Laws

UC Berkeley, Andrew Packard, Honeywell, Pete Seiler, U Minnesota, Gary Balas

APPROACH/TECHNICAL CHALLENGES• Analysis based on Lyapunov/storage fcn method• Non-convex sum-of-squares (SOS) optimization• Merge info from conventional simulation-based

assessment methods to aid in the nonconvex opt• Unfavorable growth in computation: state order,

vector field degree and # of uncertainties.• Reliance on SDP and BMI solvers, which remain

under development, unstable and unreliable

ACCOMPLISHMENTS/RESULTS Pointwise-max storage functions Parameter-dependent storage functions Benefits of employing simulations

Long-Term PAYOFFDirect model-based analysis of nonlinear systemsOBJECTIVES• Develop robustness analysis tools applicable to

certification of flight control laws: quantitative analysis of locally stable, uncertain systems

• Complement simulation with Lyapunov-based proof techniques, actively using simulation

• Connect Lyapunov-type questions to MilSpec-type measures of robustness and performance

Region-of-attractionDisturbance-to-error gainVerify set containments in state-space with SOS proof certificates.

1V

1p

2p

3p

x

0fdx

dV

1V

x .

FY04 FY05 FY06 FY07 FY08

AFOSR Funds 97 141

Other 0 0

Aid nonconvex proof search (Lyapunov fcn coeffs) with constraints from simulation

Convex outer bound

Page 2: FUNDING ($K) TRANSITIONS “Stability region analysis using sum-of-squares programming,”

•Unseeded PENBMI solutions (red)•500 simulations•50 samples of Lyapunov outer bound set

•PENBMI solutions seeded with samples. Improved estimate, consistent and reliable execution

Region of attraction estimate for 2211221 1, xxxxxx

Constraints from simulation effectively aid nonconvex search for Lyapunov function proving

region-of-attraction “radius”

A. Packard/ UC Berkeley, P. Seiler/Honeywell, G. Balas / University of Minnesota

Convex outer bound

Convex Constraints on Lyapunov coefficients, obtained from simulation. Initialize nonconvex

search within this set

0 0.2 0.4 0.6 0.8 10

2

4

6

8

4th order V, LP

0 0.2 0.4 0.6 0.8 10

10

20

30

40

4th order V, BMI

0 0.2 0.4 0.6 0.8 10

5

10

6th order V, LP

0 0.2 0.4 0.6 0.8 10

10

20

30

40

50

6th order V, BMI

samples

PENBMI results, seeded with samples