inertia relief

A subset of static analysis, inertia relief is normally used to allow static solutions of models that are not stable. Typical modeling applications are aircraft in flight, cars in motion, and spacecraft in orbit. Each of these structures has one or more unconstrained, rigid body motions. Therefore, it is not possible to solve these problems using conventional static analysis. Inertia relief provides an approach that can solve problems containing mechanisms or rigid body modes.

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