To Define Preferences for Dynamic Analysis
For this procedure you must be on the Preferences tab of the Analysis Definition dialog box and have selected Dynamic under Type.
1. Under Graphical display, select one of the following:
Length and rate
Length and frame count
Rate and frame count
2. Enter the relevant information in the Duration, Frame count, Frame rate, and Minimum interval fields.
3. Select one of the following options in the Locked entities area:
Click and select a rigid body as the lead body, then a set of follower bodies to be locked to the lead body. The follower bodies stay fixed relative to the lead body during the analysis.
Click and select a connection to be locked. The connection's allowed movements are locked during the analysis.
Click and select a connection to be disabled.
The name of the locked or disabled connection appears in the Locked entities list.
* 
Click to delete unwanted locking/disabling constraints from the list.
4. To set the model's starting conditions, select an option under Initial configuration:
a. Click Current to use the current screen configuration.
b. Click I.C.State (or Snapshot) and choose a previously saved initial condition or snapshot.
5. If you selected I.C.State, click to preview the configuration associated with that state.