Rotational ICs

Use the Rotational IC Sets tool to define rotational velocity for one or more parts.

Velocity initial conditions can be used to set parts into motion immediately with a prescribed velocity. In this way no "ramp up" time is required, unlike what you see when using a speed motor which has a profile function that begins from zero speed.

Location: Motion ribbon, Forces group, Velocity ICs

Click the satellite icon that appears when you hover over the Velocity ICs icon to view a list of all initial conditions in your model.

Add/Edit Rotational ICs Sets

  1. Select parts to add to the set.
    Note: You can also select rigid groups, or use box selection to select multiple parts.
  2. Click to finalize the set.
  • Press Ctrl as you select the Rotational ICs tool to edit the last IC set you created.
  • You can control the orientation of the IC depending on how you make part selections.
    • If a face is selected, the IC is perpendicular to selected face.
    • If a hole is selected, the IC is aligned with the hole axis.
    • If parts are box selected, the IC is perpendicular to the box selection window.
  • If Free is selected as the reference frame, the parts in a rotational IC set will rotate and also translate slightly. The direction of the translation is determined by the position of the graphical manipulator representing the initial conditions set.
  • Applying multiple ICs of the same type on the same part will cause an error. You can exclude ICs by using the Suppress option in the Model Browser context menu.
  • The counter above the Velocity ICs icon displays the number of visible and unsuppressed ICs.
  • One way to get an idea of the effect of velocity ICs on a given part in isolation would be to suppress connections on that part, turn gravity off, and run motion analysis.

Microdialog Options

Use the options in the microdialog to edit the behavior and appearance of the IC set.

Reverse Direction
Use the +/- button to reverse the direction of rotation.
Set Magnitude
Enter a magnitude for the angular velocity.
Set Reference Frame
Specify a reference system. Note that black glyphs appear upon creation and update live as you edit. They serve as a visual preview of where parts will begin to translate and rotate.
  • Positionable: You are free to position the IC using the Move tool.
  • Each CG: Each part will rotate around its own center of gravity.
  • System: The direction is dictated by the selected local system.
Switch to Component Mode
Click the icon to toggle between direction mode or component mode. Click the to orient the initial condition set by entering either a direction and magnitude (X, Y, and Z) or components (VX, VY, VZ).
Opens the Move tool so that you can move the location of the graphical manipulator representing the IC set. You might want to do this to make the manipulator easier to select.
Align to Global X/Y/Z Axis
Align the initial velocity direction so that it rotates along the X, Y, or Z axis. Using the X/Y/Z buttons when reference frame is set to System will align the direction with the local x/y/z system, not the global system.
Move to Center of Gravity
Resets the IC’s position to the center of gravity, which is the location where it was initially created. Not available if System is selected for the reference frame.