Dummy Positioning

Position a dummy model using the Dummy Browser.

Dummy Browser

Overview of the Dummy Browser.

From the menu bar, click Safety > Dummy Positioner.

Restriction: Only available in the LS-DYNA and Radioss solvers.

This browser is compatible with all LS-DYNA and Radioss Humanetics dummies (encrypted or not encrypted) and also with LSTC dummies.

You can undo and redo actions made in the browser using the Undo and Redo commands on the Restore toolbar.

The Dummy Browser consists of two panes. The first pane displays the dummy structure which consists of the different bodies defining the dummy model. The second pane displays the Entity Editor in which positioning parameters for each dummy articulations can be defined.


Figure 1.
The following data is displayed in the Dummy Browser:
Column Description
Entity List of the dummies and dummy bodies.
ID Displays the dummies and bodies IDs.
Color Displays the body entity colors.

Body color is different from the component color defined in the Model Browser. The body color is activated when a body is in Review mode or when display mode is set on “By Body”.

Entity Editor

The Entity Editor is used to assign, modify and quickly view the attributes defined inside Dummy Browser entities.

In the Entity Editor you can define the H-Point coordinates or apply Global rotations on the dummy to position the dummy in space. The H-Point coordinates can be directly specified in the fields, or by clicking on the blue arrow, which then enables you to select a target location by picking a node in the graphics area.


Figure 2.
Global rotations on the dummy can also be defined. The magnitude of the rotation can be modified, using the up and down arrow buttons. Moreover, you can control the increments of the operations by changing the Increment value.


Figure 3.

The Entity Editor is also used to modify the position of bodies. You can directly define the angle of rotation to apply in each axis of rotations in which the selected body is able to move.

The magnitude of the rotation can be also modified, using the up and down arrow buttons. Moreover, you can control the increments of the operations by changing the Increment value.


Figure 4.

Context Menu

Option Available for Description
Define Position Dummy Save the displayed position of the dummy by creating a New position or by overwriting an existing position.
Retrieve Position Dummy Position the dummy to its initial position or to another position by selecting this in the list of the saved positions.
Move Limbs Dummy Open the Entity Editor to define the position of the dummy using the automatic move to target functionality.
Positioning File Dummy Import or export a positioning file (*.daf) containing the position values of the dummy.
Pre-Simulation Dummy Export an input deck, for the appropriate solver, in order to simulate the deformation of the dummy.
Show Dummy and Bodies Displays the entity in the graphics area. The entities icon changes to bold indicating that the display state is on.
Hide Dummy and Bodies Turns off the entity in the graphics area. This selection affects each entities local display control, that is, will make the icon become ghosted indicating the display state is off.
Isolate Dummy and Bodies Displays only the selected entities, and turns off all other entities of the same type.
Review Dummy Display the dummy articulations and bodies in a simplified display mode.
Reset Review Dummy Resets the review of the previously selected entity.

Supported Entities

The Dummy () is the root of the hierarchy in the Dummy Browser. A dummy is defined by bodies () representing the different kinematic assemblies of the dummy.

Position Dummies

Position the Body Manually

  1. In the Dummy Browser, select a body.
  2. In the graphics area, click-and-drag the manipulator to interactively modify the position of the selected body.


    Figure 5.

Position the Body Automatically

  1. In the Dummy Browser, right-click on a body and select Move Limbs from the context menu.
    The Entity Editor opens.


    Figure 6.
  2. In the Multiple pairs field, select No (apply option to a single node) or Yes (apply option to a set of nodes and targets).
  3. If Multiple pairs is set to Yes, click Select pairs to open the Select multi nodes dialog and select nodes and target point pairs.
  4. Define a Node of a body.
  5. Define the Target location.
  6. Click Select Bodies to open the Dummy Bodies DOF dialog and select the bodies and degrees of freedom of the active bodies that will be able to move during automatic positioning.
    Select bodies by activating their corresponding checkbox, or picking them in the graphics area (right-click or left-click to activate/deactivate a body). Lock/unlock degrees of freedom by clicking the lock icon, or by picking the DOF arrows in the graphics area (right-click or left-click to activate/deactivate a DOF).


    Figure 7.
  7. Click Move to start the automatic positioning process.
  8. Click Save to save the achieved position.
    A name will be appended to the New position name field.

Contact Detection with Surrounding Components

Auto-contact detection allows you to automatically detect contact between dummy limbs and surrounding structural components during the positioning process. Limb motion is automatically stopped on contact detection.

  1. In the Dummy Browser, select the dummy body.
  2. In the Entity Editor, select either single contact or multiple contacts that need to be defined by setting Multiple contacts to Yes or No.
  3. For each contact, create and assign a set of components in the Contact set part field.
  4. In the Gap factor field, type in an appropriate scale factor.
  5. Click Close.
    The Contact checkbox is activated for the selected dummy body indicating the contact check is active.


    Figure 8.

Setup Pre-Simulation

Export an input deck to simulate the deformation of the dummy.

Before you begin, Position Dummies.


Figure 9.

The method used for the pre-simulation is known as the “cable” method, which uses 1D elements connected to dummy bodies, in order to pull them from their initial position to their final position.

All “cables” are automatically created on each dummy body and all boundary conditions needed for the pre-simulation.

The simulation result files can be imported to update the initial FE model and thus remove the intersections and penetrations between the dummy components.

There are two methods to perform the dummy pre-simulation:
  • Only Dummy: Export the solver files to perform the simulation of the dummy deformation only.
  • Dummy with Seat: Export the solver files to perform the simulation of the dummy and the seat deformation in one step.

Only Dummy

  1. In the Dummy Browser, right-click on the dummy and select Pre-Simulation > Only Dummy from the context menu.
  2. In the PreSimulation Tool dialog, define settings accordingly.
    1. In the PreSimulation type field, select a unit system.

      The unity system will automatically set the default simulation parameters to the correct unit. In any case, you can still modify these values manually.

    2. In the Reference Position field, select the Position that will define the starting position of the dummy in the pre-simulation.
      Per default, the Initial Position of the dummy is selected.
    3. Select the Simulation Method.
      Single File: Creates the solver deck for the pre-simulation by exporting a single file with the dummy and the load case.
      Pre-defined Include Files: Select the original Dummy include file in its reference position. An include file for the simulation load case and a master file is created, combining the selected dummy include and the load case include.
    4. In the Export File field, enter the pre-simulation deck name and directory.
      Per default, a deck with the name "result" is exported into the ~…/Local/Temp directory.
  3. Define PreSimulation Tool Options accordingly.
  4. Click Export.
The pre-simulation deck is exported to the specified location.

Dummy With Seat

  1. In the Dummy Browser, right-click on the dummy and select Pre-Simulation > Dummy with Seat from the context menu.
  2. In the PreSimulation Tool dialog, define settings accordingly.
    1. In the PreSimulation type field, select a unit system.
      The unity system will automatically set the default simulation parameters to the correct unit. In any case, you can still modify these values manually.
    2. In the Reference Position field, select the Position that will define the starting position of the dummy in the pre-simulation.
      Per default, the Initial Position of the dummy is selected.
    3. Select the Simulation Method.
      Displacement Based: Creates the needed cable and load case with a control displacement of the cable. This method ensures that the cable displacements are reached at the end of the simulation.
      Force Based: Creates the needed cable and load case with an imposed pre-load in the cables. This method cannot ensure that the final cable displacements are reached at the end of the simulation.
    4. Select the Seat components which are needed to check the intersections with the dummy and create the contacts for the simulation.
    5. Select Fixed nodes on the seat.
    6. Select the dummy direction in which the dummy will be pulled on the seat.
    7. Select the Simulation Method.
      Single File: Create the solver deck for the pre-simulation by exporting a single file with the dummy and the load case.
      Pre-defined Include Files: Select the original Dummy include file in its reference position. An include file for the simulation load case and a master file is created, combining the selected dummy include and the load case include.
    8. If the Pre-defined Include Files method is selected, select:
      The original dummy include file in its reference position.
      The original Seat include file.
    9. In the Export File field, enter the pre-simulation deck name and directory.
      Per default, a deck with the name "result" is exported into the ~…/Local/Temp directory.
  3. Define PreSimulation Tool Options accordingly.
  4. Click Export.
    To update the model with simulation results, import the simulation result file, which allows the dummy node's coordinates to be updated and element initial stress state to be defined.
    • For LS-DYNA, click Import dynain File to find the .dynain file.
    • For Radioss, click Import h3d File to find the .h3d file.

PreSimulation Tool Options

Overview of supported options in the PreSimulation Tool.

LS-DYNA

Simulation Parameter
Simulation Time
Define the total simulation time in *CONTROL_TERMINATION for the pre-simulation.
Default value = 250ms.
First Step Simulation Time: Defines the duration time for the dummy deformation simulation step (valid for the Dummy with Seat option only). Default value = 150ms
Second Step Simulation Time: Defines the duration for the seat deformation simulation step (valid for the Dummy with Seat option only). Default value = 100ms
Time Step
Define the control time step value in *CONTROL_TIMESTEP for the pre-simulation.
Default value = 0.001ms.
Force in cables (valid for the Forced Based option only)
Define the pre-tension force to be applied on the cable elements in *MAT_CABLE_DISCRETE_BEAM.
Default value = 1.0 kN.
Force ramp up time (valid for the Forced Based option only)
Define the ramp-up time for the pre-tension force in *MAT_CABLE_DISCRETE_BEAM.
Default value = 10.0ms.
Damping on cables (valid for the Forced Based option only)
Define the damping value on the discrete elements in *MAT_DAMPER_VISCOUD.
Default value = 0.5.
Cable Stiffness (valid for the Displacement Based option only)
Define the stiffness in the cable for the displacement-based simulation method.
Default value = 0.1kN/mm
Global damping value
Define the system damping constant in *DAMPING_GLOBAL.
Default value = 0.05.
Initial Stress Results
Import *INITIAL_STRESS_SOLID
Import the initial stresses for solid elements from the .dynain file.
Import *INITIAL_STRESS_SHELL
Import the initial stresses for shell elements from the .dynain file.
Import *INITIAL_STRESS_BEAM
Import the initial stresses for beam elements from the .dynain file.

Radioss

Simulation Parameters
Generate XREF for initial stresses
Create /XREF cards for the dummy components which are compatible with this RADIOSS feature in terms of material type and element formulation. The XREF cards are generated within the original session during the export of the pre-simulation deck, and not during import of .h3d file.
Simulation time
Define the total simulation time in /RUN card for the pre-simulation.
Default value = 250ms
Time Step
Define the control time step value in /DT/NODA/CST card for the pre-simulation.
Default value = 0.001ms.
Global damping value
Define the system damping constant in /DAMP card.
Default value = 0.05
Create rigids for end bodies
Automatically rigidify the end bodies (feet, hands, head) of the dummy during the pre-simulation.

Read Positioning Files

In the Dummy Browser, right-click on the dummy root name and select Positioning File > Import from the context menu.
Once the positioning file (*.daf) is read, the dummy will automatically be positioned according to the imported position data.