Setting Mechanism Preferences

You can define the settings of a mechanism to specify the options and initial states to consider during the computation of the mechanism, and improve the performance of the simulation.

Before you begin: Create a mechanism.
Note: The Mechanism Settings element is created automatically under the Globals node of each mechanism. You cannot delete or copy the Globals node under another mechanism.
  1. To edit the mechanism settings, in the tree, under the Globals node of the mechanism, do one of the following:
    • Double-click Mechanism Settings .
    • Right-click Mechanism Settings and, from context menu, select Definition.
  2. In the Limit and Contact Handling section of the Mechanism Setting dialog box, specify the behavior of the mechanism solve and initial state solve during the simulation.

    During the mechanism solve and initial state solve, the app updates and considers the states and initial conditions of the mechanism elements at the start of the simulation. For more information, see Solving Mechanisms and Solving the Initial State of Mechanisms.

    • Select the Consider Joint Limits during Mechanism Solve check box to consider the initial state of joints during the mechanism simulation (initial value, minimum value, maximum value).
      Note: Clear the check box to ignore the initial state of joints during the simulation.
    • Select the Consider Contact during Mechanism Solve check box to consider contact between bodies during the mechanism simulation.
      Note: Clear the check box to ignore contact between bodies during the simulation.
  3. To modify the time integration tolerance considered during a dynamic simulation, in the Dynamics section, under Tolerances, enter a tolerance value in the General box.

    The default tolerance value is 1e-05. It corresponds to the position tolerance, and is used to define automatically the relative and velocity tolerances.

    Tip: To obtain more accurate results during the computation of the simulation, you can increase the tolerance value.

    You can also enter a smaller step size in the result output settings of the computed analysis steps to generate a more precise interpolation between time steps and obtain more accurate results. For more information, see Creating Analysis Steps.

    Note: The computation time increases when you reduce the step size or increase the tolerance value for dynamics simulations.

  4. Click OK.