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Constrained Dynamics. f. x. A Bead on a Wire. f. x. A Bead on a Wire. Zero rate-of-change ensures constant C!. f. x. A Bead on a Wire. f. x. A Bead on a Wire. f. x. A Bead on a Wire. However, one equation cannot solve two unknowns of f-hat!?. f. A Bead on a Wire. x.
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f x A Bead on a Wire
f x A Bead on a Wire Zero rate-of-change ensures constant C!
f x A Bead on a Wire
f x A Bead on a Wire
f x A Bead on a Wire However, one equation cannot solve two unknowns of f-hat!?
f A Bead on a Wire x Constraint force does not produce work
Constrained Dynamics General Recipe
Q q About Constraint Force… Constraint force Q-hat induced by Q to move q along legal velocity q-dot
Q q About Constraint Force… Legal velocity q-dot is to the hyperplane spanned by the gradients of all constraints. Hence, constraint force is a linear combination of all gradients.
Numerical Concerns • To account for numerical drift, we often apply numerical damping as follows:
Q x Ex: Bead in Recipe
Example: Double Pendulum l1 p1 l2 p2