Analysing Head Injury of driver seat dummy using LS-Prepost.

1. SLED TEST 1
CRASHWORTHINESS AND OCCUPANT PROTECTION IN
TRANSPORTATION SYSTEM 1(ME8020)
Aniket Dighe(ge4310)
Objective- To successfully run the sled crash test and plot HIC.

2. MODELS
USED
Coarse Dummy
Sled
Steering wheel with airbag
Seatbelt

3. SIMILAR UNITS, MATERIALS
• Checked all models for units and material in LS-PrePost.
• Using conversion factors units of models are converted which has different
units.
• All models are converted to MKS units and materials found to be good.
• Length of dummy was in mm, converted to meters.
• Mass and length of steering converted to MKS system.
• Limb operation tree is copied from original coarse dummy to converted
dummy.

4. ERROR CHECK FOR ALL MODELS
• All models were checked in LS-PrePost individually for any errors in model
checking.
• If there are no errors all models were checked on grid to confirm normal
termination.
• For error termination I went through outputfile.txt, tracked and I tried to
understand errors.
• By deleting massless nodes, filtering elements, etc tried to remove errors
by trial error method.

5. COARSE
DUMMY
• Coarse dummy in MKS
unit was imported.
• Node set was created to
assign initial value.
• Part set was created to
define contacts between
dummy and other models.

6. *SET NODE &
*SET PART
• *SET NODE AND *SET
PART for dummy created
in SetD as shown in
pictures.

7. SLED
• Sled was imported using
import>ls dyna keyword
file>import offset
• Import offset is used to
avoid merging of elements
and nodes number

8. DUMMY &
SLED
CONTACTS
• *Automatic Surface to
Surface contact is used to
define contacts between
sled and dummy to avoid
negative volume error and
penetrating of body into
each other

9. STEERING
• Steering imported and
positioned as per needed.
• *SET PART created to
define contacts between
dummy and steering.

10. LIMB OPERATION
• In DmyPos>Limb operations
Selected particular body parts to
rotate.

11. STEERING
POSITIONED
• After steering positioned
by using limb operation
hands of the dummy
rotated to show the hands
on driving wheel.

12. DUMMY AND STEERING CONTACTS
• As contacts between dummy and sled, same way automatic surface to
surface contact is used to define contact between dummy and steering
• Contact between sled and steering was not required as they were not
coming in contact any time during crash.

13. SEAT BELT
• Constrained the seatbelt
• *boundry>SPC_SET>New
ID
• And particualt nodeset
was selected.

14. SEAT BELT
• Seat belt was imported
the same way as other
models
• Contacts between seatbelt
&dummy, seatbelt &
steering , seatbelt& sled
was defined as previous.

15. INITIAL VELOCITY
• Initial velocity of 5 m/s was applied to node set of dummy
• Also checked for velocity generation card if it exist deleted that card.
As it cant take both velocity cards at same time.
• IniVel>create>velocity direction and put value>apply>done.

16. D3PLOT
• To get d3plot *Dbase>Binary_D3plot>DT appropriate value entered
according to required number of plots.
• Termination time was given.
• *Control>*Termination>EndTime.
• D3Dump value checked to make sure restart of plot.

17. BINOUT
• To obtain BINOUT file go
to
• *Dbase>Ascii_option>
Binary and choose 2

18. RUN
• Finally whole file was saved in .k format and then it was compile on grid.
• After normal termination D3plot was opened in LS-PrePost.

19. D3PLOT

20. HIC PLOT
• Hic Plot was checked by
following the procedure as
shown in image.

21. HIC15 PLOT
WITH
SEATBELT
• Plot shows
• Hic=68.57
• HIC(d)=218.1

22. HIC15 PLOT
WITHOUT
SEATBELT
• Plot shows
• Hic = 66.56
• HIC(d)=216.6

23. RESULT AND CONCLUSION
• All files were terminated normally.
• HIC number without seatbelt is less than HIC number with seatbelt.