Creating a Velocity Law Excitation

A velocity law excitation drives a command in your mechanism by associating a speed value to each time step of the kinematics or dynamics simulation. The command is defined according to a Knowledge law, rule, formula, or design table.

Before you begin: Open a kinematics or a dynamics simulation referencing a mechanism in the Mechanical Systems Experience app.
See Also
About Writing Formulas for Law Excitations
About Using Design Tables for Law Excitations
  1. From the Scenario section of the action bar click Velocity Law Excitation .

    The Velocity Law Excitation dialog box appears.

  2. In the tree, select the command under the mechanism representation to drive with the excitation.
  3. Define the parameters of the position motor excitation.
  4. To modify the maximum force or torque the excitation can develop to reach its position or velocity:
    1. Click Edit Maximum Torque or Edit Maximum Force, depending on the command type.
    2. Click the arrows to increase or decrease the value.

      Tip: To modify the time step, right-click the value, and select Change Step.

    Note: During a dynamics simulation using the Symplectic Euler integrator, the maximum force or torque value is taken into account to prevent movement when joint limits are reached or when contacts occur.
    Important: The mechanism movement may be partial or may not reach the specified target when:
    • the internal torque or force required to move the mechanism exceeds the maximum value.
    • a joint limit is reached
    • a contact occurs.

  5. Click OK to save the excitation.
    The Velocity Law Excitation appears under the Scenario node.