Dirac structures and geometry of nonholonomic constraints

Dirac structures and geometry of nonholonomic constraints Dirac structures and geometry of nonholonomic constraints

27.10.2013 Views

Example Lagrangian system with constraints: a sleigh on a horizontal plane Q = R 2 × S 1 ∋ (x, y, ϕ), ∆Q(x, y, ϕ) = {( ˙x, ˙y, ˙ϕ) : ˙x sin(ϕ) = ˙y cos(ϕ)}, ∆Q = 〈 ∂ ∂ , cos(ϕ) ∂ϕ ∂x + sin(ϕ) ∂ ∂y 〉 L(x, y, ϕ, ˙x, ˙y, ˙ϕ) = m 2 ( ˙x 2 + ˙y 2 ) + I 2 ˙ϕ2 KG (KMMF) Seminarium Geometryczne 13 X 2010 22 / 26

Example Equations for a curve t ↦−→ (x(t), y(t), ϕ(t), px(t), py (t), π(t)) ˙x = px/m, ˙px = µ(t) sin ϕ ˙y = py /m, ˙py = −µ(t) cos ϕ ˙ϕ = π/m, ˙π = 0 ˙x sin ϕ = ˙y cos ϕ Solution (momentum) π(t) = π0 px(t) = p0 cos( π0 t + ϕ0) I py (t) = p0 sin( π0 t + ϕ0) I KG (KMMF) Seminarium Geometryczne 13 X 2010 23 / 26

Example<br />

Lagrangian system with <strong>constraints</strong>: a sleigh on a horizontal plane<br />

Q = R 2 × S 1 ∋ (x, y, ϕ),<br />

∆Q(x, y, ϕ) = {( ˙x, ˙y, ˙ϕ) : ˙x sin(ϕ) = ˙y cos(ϕ)},<br />

∆Q = 〈 ∂ ∂<br />

, cos(ϕ)<br />

∂ϕ ∂x<br />

+ sin(ϕ) ∂<br />

∂y 〉<br />

L(x, y, ϕ, ˙x, ˙y, ˙ϕ) = m<br />

2 ( ˙x 2 + ˙y 2 ) + I<br />

2 ˙ϕ2<br />

KG (KMMF) Seminarium Geometryczne 13 X 2010 22 / 26

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!