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Sensitivity analysis for relaxed optimal control problems with - - PowerPoint PPT Presentation

Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control Sensitivity analysis for relaxed optimal control problems with final-state constraints eric Bonnans , Laurent Pfeiffer , and Oana


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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Sensitivity analysis for relaxed optimal control problems with final-state constraints

  • J. Fr´

ed´ eric Bonnans∗, Laurent Pfeiffer∗, and Oana Serea†

∗INRIA Saclay and CMAP, Ecole Polytechnique (France), †University of Perpignan (France)

May 2012

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Introduction

We consider... a family of optimal control problems (OCP), parametrized by a nonnegative variable θ close to 0, its value functionV (θ), a strong solution (u, y) for the value θ = 0. Our goal: computing a second-order expansion of V (θ) near 0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Introduction

The main difficulty: large perturbations in uniform norm for the control variable may occur. Our tools: the abstract methodology of sensitivity analysis, relaxation with Young measures.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

1 Relaxation of optimal control problems

Strong solutions Relaxation

2 Methodology for sensitivity analysis

Upper estimate Lower estimate

3 Application to optimal control

Multipliers Linearizations of the problem Decomposition principle

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

1 Relaxation of optimal control problems

Strong solutions Relaxation

2 Methodology for sensitivity analysis

Upper estimate Lower estimate

3 Application to optimal control

Multipliers Linearizations of the problem Decomposition principle

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Strong solutions

For a control u in L∞([0, T], Rm) and θ ≥ 0, consider the trajectory y[u, θ] solution of the following differential system:

  • ˙

yt = f (ut, yt, θ), for a. a. t in [0, T], y0 = y0. Set K = {0nE } × RnI

+. Our family of OCP’s is

Min

u∈L∞ φ(yT[u, θ]),

s.t. Φ(yT[u], θ) ∈ K. Reference problem: θ = 0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Strong solutions

For a control u in L∞([0, T], Rm) and θ ≥ 0, consider the trajectory y[u, θ] solution of the following differential system:

  • ˙

yt = f (ut, yt, θ), for a. a. t in [0, T], y0 = y0. Set K = {0nE } × RnI

+. Our family of OCP’s is

Min

u∈L∞ φ(yT[u, θ]),

s.t. Φ(yT[u], θ) ∈ K. Reference problem: θ = 0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Strong solutions

A control u is a R−strong solution for the reference problem if there exists η > 0 such that u is solution to the localized problem:    Min

||u||∞≤R φ(yT[u, 0]),

s.t. Φ(yT[u], 0) ∈ K, ||y[u, 0] − y||∞ ≤ η. Now, we fix u, R, and η.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Relaxation

Set: BR, the ball of Rm of radius R PR, the set of probabilities on BR, MR, the set of Young measures on [0, T] × BR, defined by L∞([0, T], PR). For µ ∈ MR, denote by y[µ, θ] the solution to

  • ˙

yt =

  • BR f (u, yt, θ) dµt(u),

y0 = y0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Relaxation

Set: BR, the ball of Rm of radius R PR, the set of probabilities on BR, MR, the set of Young measures on [0, T] × BR, defined by L∞([0, T], PR). For µ ∈ MR, denote by y[µ, θ] the solution to

  • ˙

yt =

  • BR f (u, yt, θ) dµt(u),

y0 = y0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Relaxation

Example: for µt = 1

2δu1

t + 1

2δu2

t , the dynamic is:

˙ yt[µ, θ] = 1 2f (u1

t , y[µ, θ], θ) + 1

2f (u2

t , y[µ, θ], θ).

and can be approximated by this control:

T

() with probability 1/2 () with probability 1/2

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Relaxation

Example: for µt = 1

2δu1

t + 1

2δu2

t , the dynamic is:

˙ yt[µ, θ] = 1 2f (u1

t , y[µ, θ], θ) + 1

2f (u2

t , y[µ, θ], θ).

and can be approximated by this control:

T

() with probability 1/2 () with probability 1/2 v()

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Relaxation

We relax the OCP’s as follows    V (θ) = Min

µ∈MRφ(yT[µ, θ]),

s.t. Φ(yT[µ], θ) ∈ K, ||y[µ, θ] − y||∞ ≤ η. Theorem Under some qualification assumptions, the relaxed and the classical OCP’s have the same value. Therefore, µt = δut is a relaxed solution for θ = 0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

1 Relaxation of optimal control problems

Strong solutions Relaxation

2 Methodology for sensitivity analysis

Upper estimate Lower estimate

3 Application to optimal control

Multipliers Linearizations of the problem Decomposition principle

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

Consider the family of optimization problems: V (θ) = Min

x∈H f (x, θ)

s.t. g(x, θ) ∈ K, where K stands for inequalities and equalities. The Lagrangian is L(x, λ, θ) = f (x, θ) + λ, g(x, θ). Consider x an optimal solution for θ = 0, Λ the set of Lagrange multipliers associated with x.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

Consider the family of optimization problems: V (θ) = Min

x∈H f (x, θ)

s.t. g(x, θ) ∈ K, where K stands for inequalities and equalities. The Lagrangian is L(x, λ, θ) = f (x, θ) + λ, g(x, θ). Consider x an optimal solution for θ = 0, Λ the set of Lagrange multipliers associated with x.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

Let d and h be in H, set yθ = x + dθ + hθ2, then, f (yθ, θ) = f (x, 0) + Df (x, 0)(d, 1) θ +

  • Dxf (x, 0)h + 1

2D2f (x, 0)(d, 1)2 θ2 + o(θ2), g(yθ, θ) = g(x, 0) + Dg(x, 0)(d, 1) θ +

  • Dxg(x, 0)h + 1

2D2g(x, 0)(d, 1)2 θ2 + o(θ2).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

By a regularity metric theorem, if Dg(x, 0)(d, 1) ∈ TK(g(x, 0)), and Dxg(x, 0)h + 1 2D2g(x, 0)(d, 1) ∈ T 2

K

  • g(x, 0), Dg(x, 0)(d, 1)
  • ,

then, there exists ˜ xθ = x + dθ + hθ2 + o(θ2) such that g(˜ xθ, θ) = 0.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

By a regularity metric theorem, if Dg(x, 0)(d, 1) ∈ TK(g(x, 0)), and Dxg(x, 0)h + 1 2D2g(x, 0)(d, 1) ∈ T 2

K

  • g(x, 0), Dg(x, 0)(d, 1)
  • ,

then, there exists ˜ xθ = x + dθ + hθ2 + o(θ2) such that g(˜ xθ, θ) = 0.

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Upper estimate

This justifies the two linearized problems: at the first order, Min

d∈H Df (x, 0)(d, 1)

s.t. Dg(x, 0)(d, 1) ∈ TK(...). (LP) Its dual is: Max

λ∈Λ DθL(x, λ, 0).

(LD)

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

at the second order, for d in S(LP),    Min

h∈H

Dxf (x, 0)h + 1

2D2f (x, 0)(d, 1)2

s.t. Dxg(x, 0)h + 1

2D2g(x, 0)(d, 1)2 ∈ T 2 K(...).

(QP(d)) Its dual is: Max

λ∈S(LD)D2L(x, λ, 0)(d, 1)2.

(QD(d)) Finally, V (θ) ≤ V (0) + Val(LP)θ + Min

d∈S(LP)

  • Val(QP(d))
  • θ2 + o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Upper estimate

at the second order, for d in S(LP),    Min

h∈H

Dxf (x, 0)h + 1

2D2f (x, 0)(d, 1)2

s.t. Dxg(x, 0)h + 1

2D2g(x, 0)(d, 1)2 ∈ T 2 K(...).

(QP(d)) Its dual is: Max

λ∈S(LD)D2L(x, λ, 0)(d, 1)2.

(QD(d)) Finally, V (θ) ≤ V (0) + Val(LP)θ + Min

d∈S(LP)

  • Val(QP(d))
  • θ2 + o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Lower estimate

Denote by C(x) the critical cone: C(x) =

  • d, Dxf (x, 0)d = 0 & Dxg(x, 0)d ∈ TK(g(x, 0))
  • and the sufficient second order condition:

   for some α > 0, for all d in C(x), Max

λ∈S(LD)

  • D2

x L(x, λ, 0)d2

≥ α|d|2. (SC2) Then, up to a subsequence, with a proof by contradiction, the solutions xθ satisfy: xθ − x θ − →

θ↓0 d ∈ S(LP).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Lower estimate

Denote by C(x) the critical cone: C(x) =

  • d, Dxf (x, 0)d = 0 & Dxg(x, 0)d ∈ TK(g(x, 0))
  • and the sufficient second order condition:

   for some α > 0, for all d in C(x), Max

λ∈S(LD)

  • D2

x L(x, λ, 0)d2

≥ α|d|2. (SC2) Then, up to a subsequence, with a proof by contradiction, the solutions xθ satisfy: xθ − x θ − →

θ↓0 d ∈ S(LP).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Lower estimate

With a Taylor expansion, for all λ in S(LD), V (θ) − V (0) = f (xθ, θ) − f (x, 0) ≥ L(xθ, λ, θ) − L(x, λ, 0) = θDθL(x, λ, 0) + θ2 2

  • D(x,θ)2L(x, λ, 0)

xθ − x θ , 1 2 + o(θ2) ≥ θDθL(x, λ, 0) + θ2 2

  • Min

d∈S(LP)D(x,θ)2L(x, λ, 0)(d, 1)2

+ o(θ2). Finally, V (θ) ≥ V (0) + Val(LP)θ + Min

d∈S(LP)

  • Val(QP(d))
  • θ2 + o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Lower estimate

With a Taylor expansion, for all λ in S(LD), V (θ) − V (0) = f (xθ, θ) − f (x, 0) ≥ L(xθ, λ, θ) − L(x, λ, 0) = θDθL(x, λ, 0) + θ2 2

  • D(x,θ)2L(x, λ, 0)

xθ − x θ , 1 2 + o(θ2) ≥ θDθL(x, λ, 0) + θ2 2

  • Min

d∈S(LP)D(x,θ)2L(x, λ, 0)(d, 1)2

+ o(θ2). Finally, V (θ) ≥ V (0) + Val(LP)θ + Min

d∈S(LP)

  • Val(QP(d))
  • θ2 + o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

1 Relaxation of optimal control problems

Strong solutions Relaxation

2 Methodology for sensitivity analysis

Upper estimate Lower estimate

3 Application to optimal control

Multipliers Linearizations of the problem Decomposition principle

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Multipliers

Let us define: the end-point Lagrangian Φ[λ], Φ[λ](y, θ) = φ(y, θ) + λ, Φ(y, θ), the Hamiltonian H, H[p](u, y, θ) = p, f (u, y, θ), the costate pλ associated with λ in NK(Φ(yT, 0)), the solution to

  • ˙

pt = −Hy[pt](ut, yt, 0) pT = ΦyT [λ](yT, 0).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Let λ ∈ NK(Φ(yT, 0)), λ is said to be: a Lagrange multiplier if for a.a. t, DuH[pλ

t ](ut, yt, 0) = 0,

a Pontryagin multiplier if for a.a. t, for all u in BR, H[pλ

t ](ut, yt, 0) ≤ H[pλ t ](u, yt, 0).

The associated sets ΛL and ΛP satisfy ΛP ⊂ ΛL. Theorem (Pontryagin’s principle) Under a qualification condition, if u is an R-strong solution, then ΛP = ∅. In the sequel: “f [t] = f (ut, yt, 0)”.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Linearizations of the problem

Define ξθ, the solution to ˙ ξθ

t =

Dyf [t]ξθ

t + Dθf [t],

ξθ

0 =

0, z[v], the standard linearization

  • ˙

zt[v] = Dyf [t]zt[v] + Duf [t]vt, z0[v] = 0. ξ[µ], the Pontryagin linearization ˙ ξt[µ] = Dyf [t]ξt[µ] +

  • UR f (u, yt, 0) − f [t] dµt(u),

ξ0[µ] = 0,

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Linearizations of the problem

We consider two kinds of paths, the “standard” ones: uθ = u + vθ, for which φ(yT[uθ, θ], θ) − φ(yT, 0) = Dφ(yT, 0)(zT[v] + ξθ

T, 1)θ + o(θ),

the “Pontryagin” ones: µθ = (1 − θ)µ + θµ, for which φ(yT[µθ, θ], θ) − φ(yT, 0) = Dφ(yT, 0)(ξT[µ] + ξθ

T, 1)θ + o(θ),

Denote by:

  • CS =

cone

  • z[v], v ∈ L∞(0, T; Rm)
  • ,

CP = cone

  • ξ[µ], µ ∈ MR
  • .

Note that: CS ⊂ CP.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Linearizations of the problem

We consider two kinds of paths, the “standard” ones: uθ = u + vθ, for which φ(yT[uθ, θ], θ) − φ(yT, 0) = Dφ(yT, 0)(zT[v] + ξθ

T, 1)θ + o(θ),

the “Pontryagin” ones: µθ = (1 − θ)µ + θµ, for which φ(yT[µθ, θ], θ) − φ(yT, 0) = Dφ(yT, 0)(ξT[µ] + ξθ

T, 1)θ + o(θ),

Denote by:

  • CS =

cone

  • z[v], v ∈ L∞(0, T; Rm)
  • ,

CP = cone

  • ξ[µ], µ ∈ MR
  • .

Note that: CS ⊂ CP.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Linearizations of the problem

At the first-order, we can consider: the standard linearized problem and its dual    Min

ξ∈CS

Dφ(yT, 0)(ξ + ξθ

T, 1)

s.t. DΦ(yT, 0)(ξ + ξθ

T, 1) ∈ TK(Φ(yT, 0)).

(SLP) Max

λ∈ΛL

T DθH[pλ

t ][t] dt + DθΦ[λ](yT, 0)

  • .

(SLD) the Pontyragin linearized problem and its dual    Min

ξ∈CP

Dφ(yT, 0)(ξ + ξθ

T, 1)

s.t. DΦ(yT, 0)(ξ + ξθ

T, 1) ∈ TK(Φ(yT, 0)).

(PLP) Max

λ∈ΛP

T DθH[pλ

t ][t] dt + DθΦ[λ](yT, 0)

  • .

(PLD)

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Linearizations of the problem

At the first-order, we can consider: the standard linearized problem and its dual    Min

ξ∈CS

Dφ(yT, 0)(ξ + ξθ

T, 1)

s.t. DΦ(yT, 0)(ξ + ξθ

T, 1) ∈ TK(Φ(yT, 0)).

(SLP) Max

λ∈ΛL

T DθH[pλ

t ][t] dt + DθΦ[λ](yT, 0)

  • .

(SLD) the Pontyragin linearized problem and its dual    Min

ξ∈CP

Dφ(yT, 0)(ξ + ξθ

T, 1)

s.t. DΦ(yT, 0)(ξ + ξθ

T, 1) ∈ TK(Φ(yT, 0)).

(PLP) Max

λ∈ΛP

T DθH[pλ

t ][t] dt + DθΦ[λ](yT, 0)

  • .

(PLD)

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Linearizations of the problem

Note that: Val(PLP) ≤ Val(SLP). Theorem Under a qualification condition, the following estimate holds: V (θ) ≤ V (0) + Val(PLP)θ + o(θ). Two difficulties arise now: problem PLP does not have necessarily solutions impossible to compute second-order expansions with Pontryagin paths. Therefore, we suppose that Val(PLP) = Val(SLP).

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Linearizations of the problem

Note that: Val(PLP) ≤ Val(SLP). Theorem Under a qualification condition, the following estimate holds: V (θ) ≤ V (0) + Val(PLP)θ + o(θ). Two difficulties arise now: problem PLP does not have necessarily solutions impossible to compute second-order expansions with Pontryagin paths. Therefore, we suppose that Val(PLP) = Val(SLP).

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Linearizations of the problem

At the second order, we “mix” linearizations. For v ∈ S(SLP), set µθ = (1 − θ2) (u + vθ)

  • 1st-order term

+ θ2µ

  • 2nd-order term

, with µ ∈ MR to be optimized. The dual of the second-order linearized problem is: Max

λ∈S(LD)Ωθ[λ](v),

(QD(v)) where Ωθ is the “Hessian of the Lagrangian”: Ωθ[λ](v) = D2Φ[λ](yT, 0)(zT[v] + ξθ

t , 1)

+ T D2H[pλ

t ][t](vt, zt[v] + ξθ t , 1)2 dt.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Linearizations of the problem

At the second order, we “mix” linearizations. For v ∈ S(SLP), set µθ = (1 − θ2) (u + vθ)

  • 1st-order term

+ θ2µ

  • 2nd-order term

, with µ ∈ MR to be optimized. The dual of the second-order linearized problem is: Max

λ∈S(LD)Ωθ[λ](v),

(QD(v)) where Ωθ is the “Hessian of the Lagrangian”: Ωθ[λ](v) = D2Φ[λ](yT, 0)(zT[v] + ξθ

t , 1)

+ T D2H[pλ

t ][t](vt, zt[v] + ξθ t , 1)2 dt.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Theorem The following expansion is an upper estimate of V (θ): V (0) + θVal(SLP) + θ2 2

  • Min

v∈S(SLP)

Max

λ∈S(LD)Ωθ[λ](v)

  • + o(θ2).

We can extend: the first-order linearized problem, the Hessian Ωθ, the theorem, by replacing v by a Young measure ν on [0, T] × Rm with a generalized L2 − norm (in a space denoted by M2), V (θ) ≤ V (0)+θVal(SLP)+θ2 2

  • Min

ν∈S(SLP′)

Max

λ∈S(LD)Ωθ[λ](ν)

  • +o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Theorem The following expansion is an upper estimate of V (θ): V (0) + θVal(SLP) + θ2 2

  • Min

v∈S(SLP)

Max

λ∈S(LD)Ωθ[λ](v)

  • + o(θ2).

We can extend: the first-order linearized problem, the Hessian Ωθ, the theorem, by replacing v by a Young measure ν on [0, T] × Rm with a generalized L2 − norm (in a space denoted by M2), V (θ) ≤ V (0)+θVal(SLP)+θ2 2

  • Min

ν∈S(SLP′)

Max

λ∈S(LD)Ωθ[λ](ν)

  • +o(θ2).
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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Decomposition principle

The critical cone C∞ is the set of v in L∞(0, T; Rm) such that DyT φ(yT, 0)zT[v] ≤ 0, DyT Φ(yT, 0)zT[v] ∈ TK(Φ(yT, 0)). We also define the quadratic form Ω[λ](v) by Ω[λ](v) = D(yT )2Φ[λ](yT, 0)(zT[ν]) + T D(u,y)2H[pλ

t ](ut, yt, 0)(vt, zt[ν])2 dµt(u) dt.

Like previously, we can extend C∞ to a cone C2 ⊂ M2 and Ω to elements of M2.

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Decomposition principle

Let θk ↓ 0 and µk be feasible points of the perturbed problems with θ = θk, such that d2(µk, µ) → 0. We decompose µk as follows: µA,k, where the perturbations are small in L∞−norm, µB,k, where the perturbations are large on a subset Bk. Theorem Assume that: meas(Bk) → 0 and d∞(u, µA,k) → 0, then, a lower estimate of V (θk) − V (0) is

  • Bk

H[pλ

t ](u, yt) − H[pλ t ][t] dµB,k(u) dt

+ Ω[λ](µA,k − u) + o(d2(µ, µk)2).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Decomposition principle

Let θk ↓ 0 and µk be feasible points of the perturbed problems with θ = θk, such that d2(µk, µ) → 0. We decompose µk as follows: µA,k, where the perturbations are small in L∞−norm, µB,k, where the perturbations are large on a subset Bk. Theorem Assume that: meas(Bk) → 0 and d∞(u, µA,k) → 0, then, a lower estimate of V (θk) − V (0) is

  • Bk

H[pλ

t ](u, yt) − H[pλ t ][t] dµB,k(u) dt

+ Ω[λ](µA,k − u) + o(d2(µ, µk)2).

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Decomposition principle

The strong second-order sufficient condition (SC2) is: there exists α > 0 such that

1 for almost all t, for all u ∈ BR,

sup

λ∈S(LDθ)

  • H[pλ

t ](u, yt, 0) − H[pλ t ](ut, yt, 0)

  • ≥ α|u − ut|2,

2 for all ν in C2,

sup

λ∈S(LDθ)

Ω[λ](ν) ≥ α||ν||2

2.

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We consider solutions µθ to the perturbed problem. Theorem IF (SC2) holds, for all sequence θk ↓ 0, the sequence µθk −u

θk

has a limit point for the narrow topology in S(SLP′). Moreover, ≥ V (0) + θVal(LPθ) + θ2 2

  • Min

ν∈S(SLP)

Max

λ∈S(LDθ)Ωθ[λ](ν)

  • + o(θ2).

is a lower estimate of V (θ). Sketch of the proof: we neglect the large perturbations by contradiction, d2(µ, µθ

k) = O(θk)

conclusion with decomposition principle.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

We consider solutions µθ to the perturbed problem. Theorem IF (SC2) holds, for all sequence θk ↓ 0, the sequence µθk −u

θk

has a limit point for the narrow topology in S(SLP′). Moreover, ≥ V (0) + θVal(LPθ) + θ2 2

  • Min

ν∈S(SLP)

Max

λ∈S(LDθ)Ωθ[λ](ν)

  • + o(θ2).

is a lower estimate of V (θ). Sketch of the proof: we neglect the large perturbations by contradiction, d2(µ, µθ

k) = O(θk)

conclusion with decomposition principle.

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Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Bibliography I

J.F. Bonnans, A. Shapiro, Perturbation analysis of optimization problems, Springer-Verlag, New York, 2000.

  • M. Valadier,

Young measures. In Methods of nonconvex analysis, Lecture Notes in Math., 1446:152-188, 1990. L.C. Young, Lectures on the calculus of variations and optimal control theory. W.B. Saunders Co., 1969.

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SLIDE 48

Relaxation of optimal control problems Methodology for sensitivity analysis Application to optimal control

Bibliography II

J.F. Bonnans, N. Osmolovski˘ ı, Second-order analysis of optimal control problems with control and initial-final state constraints.

  • J. Convex Anal., 17(3-4):885-913, 2010.

J.F. Bonnans, L.P., O.S. Serea, Sensitivity analysis for relaxed OCP’s with final-state constraints, Inria Research Report 7977, submitted.

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