Smooth Spider

Smooth Spider connects a node to a set of nodes in a smooth fashion.

Related Topics
Smooth Body Motion Property
Attributes
Type spider element
Physical property Smooth Body Motion Property
Mesh connectivity SPIDER
Number of nodes 1 slave, n-1 masters
Degrees of freedom (per node) 6 (3 translations and 3 rotations)
Type of behavior kinematics



The displacement of the slave node (N1) is linked to the displacement of the center of gravity of the n-1 master nodes. This linkage does not introduce any additional stiffness between the master nodes.

The relations are obtained in the following way:

  • Compute the center of gravity of the master nodes using the same weight for all the nodes. The average displacement (translations and rotations) of the center of gravity of the master nodes is computed using the Mean Squares method.
  • The slave node is linked to the center of gravity of the n-1 master nodes according to the rigid-body equations.

The master nodes should not be aligned, otherwise the rotation along the axis of alignment can not be transmitted.