Integrator Command

This command is used to construct the Integrator object. The Integrator object determines the meaning of the terms in the system of equation object Ax=B.

The Integrator object is used for the following:

   * determine the predictive step for time t+dt
   * specify the tangent matrix and residual vector at any iteration
   * determine the corrective step based on the displacement increment dU

The system of nonlinear equations is of the form:

Static analysis:Insert non-formatted text here

Transient analysis:<math>Insert formula here</math>

The type of integrator used in the analysis is dependent on whether it is a static analysis or transient analysis.

Static Integrators:

• Load Control
• Displacement Control
• Minimum Unbalanced Displacement Norm
• Arc-Length Control

Transient Integrators:

• Newmark Method
• Hilbert-Hughes-Taylor Method