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Extendidng Hamilton's Principle to Non-Holonomic sytems

  1. Jul 18, 2008 #1
    Can someone explain me how to extend Hamilton's principle to non-holonomic system's thru the lagrange undetermined multipliers?
    PS:Assume the system is Semi-Holonomic that is [tex]f_{\alpha}(q_{i},q_{2} \cdots q_{n} ,\dot{q_{1}}, \dot{q_{2}}, \cdots \dot{q_{n}})=0[/tex] such a equation exists for [tex]\alpha=1,2,3 \cdots m[/tex]
    Last edited: Jul 18, 2008
  2. jcsd
  3. Jul 19, 2008 #2


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    If by "Hamilton's Principle," you mean "the Variational Principle that Hamilton's Action is Extremized," strictly speaking, no such "Nonholonomic Constrained Action Principle" exists, except in the special case that the "nonholonomic constraints" are "integrable" --- i.e., that they are really just "disguised" holonomic constraints that have been written in an apparently non-holonomic form. (One will find a few contrary claims in a few textbooks and papers, but on careful examination, these so-called "nonholonomic variational principles" are all either ill-posed or not self-consistent unless the constraints are integrable.)

    IIRC, a mathematically rigorous treatment of constrained variational problems may be found in Rund and Lovelock's https://www.amazon.com/Tensors-Differential-Forms-Variational-Principles/dp/0486658406" but it's fairly heavy going. (Or perhaps I may be thinking of Rund's "Hamilton-Jacobi Theory of the Calculus of Variations," which is sadly now out of print...)

    There is a modification of Hamilton's Principle called the "Hamilton-Jacobi-Bellman Principle" (or just the "Bellman Principle" for short), that is used to formulate "Optimal Control Problems" --- including problems with non-holonomic constraints. However, the Bellman Principle is not in general equivalent to Hamilton Principle, and it does in general lead to equations of motion that are "mathematically degenerate" --- i.e., they have a nontrivial "nullspace," implying that their solutions are non-unique.

    There is also Dirac's Theory of Constrained Hamilitonian Systems, but Dirac's formalism cannot be derived from a variational principle except in the special case that the constraints are integrable --- i.e., the constraints are equivalent to holonomic constraints.
    Last edited by a moderator: May 3, 2017
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