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3 Geometric Constraint
ОглавлениеIn contrast with the implicit integration method the explicit method does not require a global stiffness matrix. The motion update is treated locally for each node. The nodal motion is only affected by the physical quantities around the node. As a result, DR is an ideal method to deal with local perturbations that are caused by physical contacts or geometric constraints, because the local instability will not cause the entire system to crash. The geometric constraint discussed in this paper is a curve or surface defined by the non-uniform rational basis spline (NURBS). If a structural node is constrained, its movement will be restricted within the constraint domain. The static state derived in this manner is a state that exhibits the lowest strain energy while satisfying all geometric constraints, which is crucial for combining material aspects with geometric design requirements.