ANSYS Rigid Dynamics Module

• Extremely fast solution, often measured in seconds for even complex assembly dynamics
• Configuration option that allows interactive kinematic manipulation of assembly and uncovers incorrect constraints immediately
• Iterative “what if” simulations possible; realistic manual optimization opportunity due to the very low CPU requirements of an all rigid dynamics solution
• Converting an all-rigid model to a combined rigid-flexible model takes just a few mouse clicks making model ready to run in minutes

Often measured in seconds for even complex, many part, assembly dynamics, the purpose built ANSYS Rigid Dynamics product contains an explicit solver tuned to rigid assembly mechanism simulations. With a choice of Runge Kutta 4 or Runge Kutta 5 iterative solver options, the solver chosen can be tuned for all out speed or extreme robustness, as the simulation complexity warrants. Complex time/histories, single or multiple inputs are also efficiently fitted and solved.

Multiple channel joint driver input loading for agricultural equipment simulation

The ultimate tool to determine if a model is set up correctly, the configure option is available at any time at a user’s request. Activating the configure option essentially starts the ANSYS Rigid Dynamic explicit solver up in real time mode and allows active part manipulation, and often the discovery of unexpected behavior that results from an incorrectly constrained assembly. Additional tools are available to help a user discover and troubleshoot an over-constrained model, which is a fairly commonly encountered situation, particularly with new models.

Interactive configure option allowing real time model manipulation

Running a large, multi-part model that encounters large rotations isn’t something that comes to mind immediately as a small job. However, with a model constrained to rigid only behavior and parts connected via joints, the number of degrees of freedom are often a fraction of what an equivalent FEA model would be. With solution times measured in seconds rather than hours, doing multiple simulations with various model configurations is not only possible, but prudent. The ANSYS Rigid Dynamics product, because of its inherent speed, is a realistic up front design tool in that it can not only keep pace with rapid digital prototype models, but can in fact drive changes to those prototypes based on engineering insights gained. Insights gained with a rigid model will directly benefit a flexible dynamics model as well.

Project schematic for rigid/flexible dynamics model simulation showing data sharing

While much can be learned from a rigid dynamic simulation with the ANSYS Rigid Dynamics product, the holy grail of simulation has always been flexible dynamics because of the complete results set that can answer the questions “How will this model behave in the real world”, and “Should we spend the money to make a physical prototype of this model?” Designed from the ground up to work with the flexible dynamics capabilities found in ANSYS Structural, ANSYS Mechanical and ANSYS Multiphysics, models developed and troubleshoot using ANSYS Rigid Dynamics are easily converted to selectively or completely flexible model that can be solved with implicit solvers.

Combined rigid and flexible (meshed) model of NASCAR suspension components