Assembly CreateSimulation

Assembly CreateSimulation
Menu location
Assembly → Create Simulation
Workbenches
Assembly
Default shortcut
S
Introduced in version
1.1
See also
None

Description

The Assembly CreateSimulation tool creates a simulation of the current assembly.

Usage

1. Make sure that an assembly is active.
2. There are several ways to invoke the tool:
   • Press the Create Simulation button.
   • Select the Assembly → Create Simulation option from the menu.
   • Use the keyboard shortcut: S.
3. If no Simulations object pre-exists: A Simulations container is added to the active assembly.
4. A Simulation object is added to the Simulations container.
5. The Create Simulation Task panel opens.
6. Add a Motion object:
   • Press the green plus button to open a dialog window.
   • Select one joint from the list.
   • If necessary select a Motion Type.
   • Optionally edit the Formula.
   • Press the OK button to close the dialog.
   • A new motion is added to the list.
   • Optionally repeat to create another Motion.
7. Optionally adjust the Simulation settings.
8. Press the Generate button.
9. An Animation Player section is added to the Task panel.
   • Use the player widgets to animate the assembly.
10. Press the OK button to finish the tool and close the Task panel.

Task panel

When the Create Simulation task panel is opened for the first time Motions list is empty and the Animation player is hidden.

Double-click an existing Simulation object in the Tree view to re-open the task panel and edit the parameters.

• Motions: Lists the content of the Group property, that is the Motion objects in the Simulations container.
  • button: Opens a (nameless) dialog window to add a Motion object to the Group property and updates the list.
  • button: Removes a Motion object from the Group property and updates the list.
• Simulation settings: Set the properties of the Simulation object.
  • Start: Sets the a Time Start property.
  • End: Sets the b Time End property.
  • Step: Sets the c Time Step Output property.
  • Tolerance: Sets the f Global Error Tolerance property.
• Generate button: Calculates the listed motions and adds the Animation player section to the Task panel.
• Animation player: Controls the positions of the assembled items according to the current frame.
  • Frame slider: Sets the current frame, doesn't set any property.
  • Frames Per Second: Sets the j Frames Per Second property, that is the speed of the animation.
  • Player buttons: Control the way to change the current frame, from left to right:

    Step backward, Play backward, Stop, Play forward, Step forward

Motion dialog

This dialog window creates a Motion object that acts as an actuator for a single degree of freedom (DOF) of a certain joint and sets its properties.

The extra help text appears if the Help button is pressed.
(Don't mind the appearance of the OK button, it is active and useable)

• Joint: Displays a list of all joints in the active Assembly to set the Joint property.
• Motion Type: Displays a list of available DOFs in the selected Joint to set the Motion Type property.

  (For example, we can choose between Angular, and Linear for a cylindrical joint)

• Formula: Sets the Formula property.
• Help / Hide help buttons: Toggle the visibility of the help text regarding the formulas.

Notes

• The number of frames is the difference of Start and End value divided by the Step value. (all entered in seconds giving a unitless integer number) For the default values it is: (1.0 s - 0.0 s) / 0.01 s = 100
• To achieve a complete revolution for an angular motion we can do either:
  • Enter 2 * pi * time in the Formula field and set a duration (End value - Start value) of one second under Simulation settings in the Task panel.
  • Enter 1 * time in the Formula field and set a duration (End value - Start value) of (2 * pi =) 6.283 seconds under Simulation settings in the Task panel.

Properties

See also: Property editor.

Simulations

A Simulations container is an Assembly::SimulationGroup object which is derived from an App DocumentObjectGroup object and inherits all its properties. It has no additional properties.

Simulation

A Simulation object is derived from an App FeaturePython object and inherits all its properties. It also has the following additional properties:

Data

Base

• DataGroup (LinkList): The Motion objects of the object.
• Data (hidden)_ Group Touched (Bool):

Simulation

• Dataa Time Start (Time): Default is 0.0 s. Simulation start time.
• Datab Time End (Time): Default is 4.0 s. Simulation end time.
• Datac Time Step Output (Time): Default is 0.01 s. Simulation time step for output.
• Dataf Global Error Tolerance (Float): Default is 1e-06. Integration global error tolerance.
• Dataj Frames Per Second (Integer): Default is 30. Frames Per Second.

View

Space

• ViewDecimals (Integer): Default is 9. The number of decimals to use for calculated texts.

Motion

A Motion object is derived from an App FeaturePython object and inherits all its properties. It also has the following additional properties:

Data

Motion

• DataFormula (String): The formula of the motion. For example 1.0*time.
• DataJoint (XLinkSubHidden): The joint that is moved by the motion.
• DataMotion Type (Enumeration): The type of the motion. The options are: Angular and Linear.