The equivalent rigid body motion output variables are specified in the results (.fil) and data (.dat) files. They can only be requested when using the direct-integration implicit dynamic procedure. These variables are considered whole element set variables, meaning that the quantity requested is summed over the element set specified. If no element set is specified, the quantity is summed over the entire model. The element set specified may contain elements which do not have mass (SPRINGs, DASHPOTs, etc.), but these elements will be ignored during the summation process. Specifying an element set in which all elements have no mass will elicit a warning message from Abaqus.
All of the verification problems below impose a rigid body motion on single element models. Each input file contains separate and distinct single element meshes corresponding to the many specific elements within that element category. For instance, the xrbmcpes.inp input file tests all of the CPE type elements and contains single element meshes for the CPE3, CPE4, CPE4R, CPE6, CPE8, CPE8R elements (and hybrid versions of all these elements). Most of the problems impose a planar 90° rotation about the z-axis; the three-dimensional continuum problem imposes an oblique rotation. Separate output requests to the results file are given for each element set in the model.