Curve mesh parameters definition

@ETA_VALUE { η1, η2,... ηn}
@COMMENTS {CommentText}


  1. When creating a finite element discretization of the multibody system, structural components will be broken into several finite elements. Structural components can be defined along a curve, 1-D components such as beam and cables), or on a surface, 2-D components such as plates and shells. This section provides the parameters that will control the meshing process. For 1-D components, these parameters fully define the mesh. For 2-D components, the mesh is defined by the parameters associated with two adjacent curves of the surface.
  2. The mesh is defined by the number of elements along the curve and their order. The curve will be broken into Nel elements, each of order oel.
    • If oel = 1, the corresponding elements will use linear shape functions; i.e. the element has two nodes.
    • If oel = 2, parabolic shape functions are used; i.e. the element has three nodes.
    • If oel = 3, cubic shape functions are used; i.e. the element has four nodes.

    For example, the discretization of a beam with the following mesh parameters, Nel = 4 and oel = 3, will feature a total of 4 × 3 + 1 = 13 nodes. Since the beam has six degrees of freedom per node, the discretization involves 13 × 6 = 78 degrees of freedom.

  3. In general, the curve will be divided into Nel elements of equal size. However, if element of unequal size are desired, the size of each element can be specified with their optional @ETA_VALUE. Nel + 1 entries must appear, the first entry must be η1 = 0.0, the last ηn = 1.0, and the non-decreasing intermediate values determine the size of the various elements. The η values correspond to the parameterization of the curve inherent to its NURBS representation.
  4. It is possible to attach comments to the definition of the object; these comments have no effect on its definition.