The GGL variational principle for constrained mechanical systems

Abstract We present an extension of the Livens variational principle (sometimes also referred to as Hamilton-Pontryagin principle) mechanical systems subject holonomic constraints. The newly proposed embodies index reduction in spirit often-applied GGL stabilization and thus may be termed “GGL principle”. Euler-Lagrange equations assume form differential-algebraic (DAEs) with differentiation two. In contrast original GGL-DAEs, formulation fits into Hamiltonian framework mechanics. Therefore, facilitates design structure-preserving integrators. particular, it offers possibility construct This is illustrated development a new first-order scheme which symplectic by design. numerical properties devised are investigated for representative examples constrained systems.