speed and safety: composite materials in motorsport - dallara automobili
DESCRIPTION
This presentation will give an insight of what safety criteria govern the design and the manufacturing of modern racing cars, such as Formula 1 and Indy cars, and will show how good engineering can be used to reduce the risk of fatalities for racing drivers. It will also explain the challenges which Dallara and Altair will face in the near future to develop new tools for the dynamic structural analysis of carbon composites structures.TRANSCRIPT
09/05/2012 1
SPEED AND SAFETY:
COMPOSITE MATERIALS IN MOTORSPORT
Altair Americas HTC – Detroit, May 16th 2012
Luca Pignacca
Chief Designer and EU Racing Business Leader
09/05/2012 2
“We wish to design and
manufacture the fastest and
the safest racing cars in the
world”
Giampaolo,
Aside from my true affection for you as a person, I love you for the passion you put
into your work of leading a truly remarkable company, which in my opinion,
builds the best and most safe race cars in the world.
We all have carried heavy hearts this week, as we lost a great man to a tragic
accident. A great man, a great husband and father, a true Champion in every
sense. In my estimation, he was in the best and safest car he could have been in
to have a chance of surviving an incident of that magnitude, as evidenced by the
fact that others were able to escape with little injury given similar
dynamics. The fact of the matter is that God had determined that it was Dan's
time to join Him in heaven, and it was simply out of our human hands. I know
Dan appreciated all of the love, passion and pride you put into doing what you do,
and was proud to be part of the development of the new car with you.
We will all miss him and we will all come together to support his family in their
time of need, as we carry on in his memory.
Regards, Tony George
09/05/2012 3
09/05/2012 4 4
DALLARA RACE CARS
IndyCar Renault World
Series 3.5 GP2
GP3 F3
Indylight
Grand-Am Formulino
09/05/2012 5 5
AUTOMOTIVE CONSULTANCIES
Bugatti Veyron 16.4 KTM X-Bow
Alfa 8C Maserati MC12
09/05/2012 6 6
COMPANY PRESENTATION
In a world of increasing competition and knowledge distribution, our company
strategy is focused on three areas of specialist knowledge:
1.Design and manufacturing
2.Aerodynamics
3.Vehicle Dynamics
09/05/2012 7
DESIGN OFFICE
09/05/2012 8
STRUCTURAL ANALYSIS
09/05/2012 9
AERODYNAMICS:
2 WIND TUNNELS and CFD
09/05/2012 10
VEHICLE DYNAMIC : MULTIBODY ANALYSIS
09/05/2012 11
INDOOR TESTING - SEVEN POSTER RIG
09/05/2012 12
OUTDOOR TESTING - TRACK SUPPORT
09/05/2012 13
R&D: DRIVING SIMULATOR
09/05/2012 14
TECHNOLOGY: THE CONNECTION BETWEEN SPEED
AND SAFETY
Low speed - High risk High speed - Low risk
"It is all about probabilities. You can never make it safe. F1 is not safe but you can do a lot of work to
reduce the probability of somebody getting hurt.”
Max Mosley
Former FIA President
09/05/2012 15
HISTORY - CHASSIS EVOLUTION
60s - Steel tubes
70s - aluminium
monocoque with
bonded and riveted
panels
80s - composite
monocoque
Continue
evolution…
INDYCAR 2012 SAFETY REQUIREMENTS AND
HOMOLOGATION TESTS
09/05/2012 16
09/05/2012 17
NOSE PUSH OFF TEST
4.000 kg – 8.810 lbs
@ midpoint between nose tip and chassis front bulkhead
After 30 seconds of application:
no failure of the structure
no failure of any attachment
between the structure and the
survival cell.
09/05/2012 18
FRONTAL CRASH TEST #1
Total trolley weight = 900 kg – 1982 lbs
Impact speed = 12 m/s
Impact energy = 65 kJ
Dummy weight = 75 kg
Fuel tank = full of water (18,5 US Gal – 154 lbs)
no damage to the monocoque
no failure of any attachment of
safety belts and fire ext.
Peak deceleration over the first
150 mm < 10 g
Average trolley deceleration < 80 g
Peak deceleration > 80 g for max
10 ms
09/05/2012 19
FRONTAL CRASH TEST #2 (on the same crash cone of #1)
Total trolley weight = 900 kg – 1982 lbs
Impact speed = 8,5 m/s
Impact energy = 33 kJ
Dummy weight = 75 kg
Fuel tank = full of water (18,5 US Gal – 154 lbs)
no damage to the monocoque
no failure of any attachment of
safety belts and fire ext.
Peak deceleration over the first
150 mm < 10 g
Average trolley deceleration < 40 g
Peak deceleration > 80 g for max
10 ms
09/05/2012 20
SAFETY STRUCTURES – NOSE BOX
Crash 2 Crash 1
09/05/2012 21
SAFETY STRUCTURES – NOSE BOX
Crash nose box 1
Crash nose box 2
09/05/2012 22
REAR IMPACT STRUCTURE PUSH OFF TEST
4.000 kg – 8.810 lbs
@ mid point of rear impact structure
After 30 seconds of application:
no failure of the structure
no failure of any attachment
between the structure and the
survival cell.
09/05/2012 23
REAR CRASH TEST
Total trolley weight = 900 kg – 1.982 lbs
Impact speed = 11,85 m/s
Impact energy = 63 kJ
no damage to the structures behind the
rear wheel axis
Average trolley deceleration < 40 g
Peak deceleration > 80 g for max 10 ms
09/05/2012 25
SAFETY STRUCTURES – REAR IMPACT STUCTURE
Video Billy Boat
09/05/2012 26
MAIN ROLL HOOP TEST
11.980 kg – 26.400 lbs
Through the main
roll hoop structure
No structural failure in a plane
100 mm – 4” below top of hoop
max deformation = 2” along the
loading axis
09/05/2012 28
SIDE STATIC TEST #1
3.000 kg – 6.610 lbs
Where “tethered”
front wheel would impact
No structural failure
max deflection = 15 mm
09/05/2012 29
SIDE STATIC TEST #2
3.000 kg – 6.610 lbs
No structural failure
max deflection = 15 mm
09/05/2012 30
COCKPIT RIM TEST
1.500 kg – 3.300 lbs
@ 250 mm from rear edge of cockpit opening
No structural failure
max deflection = 20 mm
09/05/2012 31
FUEL TANK SIDE TEST
1.500 kg – 3.300 lbs
Through the center of the fuel tank
No structural failure
09/05/2012 32
FUEL TANK BOTTOM TEST
Through the center of the fuel tank
1.250 kg
No structural failure
09/05/2012 33
SECONDARY ROLL HOOP TEST
7.500 kg – 16.520 lbs
On top of the dash bulkhead
(not requested by Indycar ,
specified by Dallara)
CALCULATION ONLY
No structural failure
max deformation = 2” along the
loading axis
09/05/2012 34
SAFETY STRUCTURES – SECONDARY ROLL HOOP
Front Roll Hoop
09/05/2012 35
SIDE CRASH LOADS TEST
1.500 kg x 4 – 3.300 lbs x 4
6.000 kg tot – 13.215 lbs tot
on the side of the cockpit area
(not requested by Indycar ,
specified by Dallara)
CALCULATION ONLY
No structural failure
09/05/2012 36
SAFETY STRUCTURES – SIDE CRASH PANEL
Video Hildebrand
09/05/2012 37
SIDE ZYLON PANELS
Red area : 12 plies of Zylon (approx 5 mm thick)
Green area : 7 plies of Zylon (approx 3 mm thick
bonded on the monocoque sides after all the static tests
09/05/2012 38
DALLARA INDYCAR 2012 SAFETY CELL (MONOCOQUE)
Carbon composite sandwich structure with aluminium honey-comb core with side
Zylon panels
Fabricated steel rool-hoop
2 x CNC machined aluminium bulkheads (dash and pedals)
Carbon composite seat back bulkhead
Complete monocoque weight = 81 kg – 178 lbs
09/05/2012 39
A LONG CFRP CALCULATION HISTORY
1985
First carbon chassis
1998
First analyses on carbon
chassis
2000
Crash box
2004
Specific tools
2008
Crash box with
FE approach
2005
Crash test of
full scale
vehicle with
carbon fiber
chassis
2011
Crash of
racing cars
09/05/2012 40
The designer can define shapes and materials which are new every time …
.. by using his creativity and a lot of material types (UD, clothes) fibers (T700,
T1000…) and “format” (GG200, GG630…)
Absorbed energy for different materials
0
10
20
30
40
50
60
70
80
90
0 50 100 150 200 250
Elastic modulus [GPa]
Sp
ecif
ic e
nerg
y a
bso
rpti
on
[J/g
]
Carbon woven
High strenght steel
Stainless steel
Aluminium alloy
Carbon UD
COMPOSITE MATERIALS : HIGH PERFORMANCE
09/05/2012 41
COMPOSITE MATERIALS : HIGH PERFORMANCE
FLWB in CFRP:
Displacement in cornering loadcase: 0.168 mm
Weight: 1.31 kg
FLWB in Steel:
Displacement in cornering loadcase: 0.165mm
Weight: 2.29 kg
Crash Cone in CFRP:
Energy absorption: 110000 J
Weight: 4.6 kg
Crash Cone in Aluminium:
Energy absorption: 110000 J
Weight: 7.8kg
09/05/2012 42
COMPOSITE MATERIALS : HIGH TECH
• Big experience and knowledge are required
• A lot of data necessary to do the analysis
• Physical phenomena very complex
KEY SYNERGIES WITH :
• The main raw material market suppliers, keeping us constantly informed about
CFRP new developments and solutions
• The main software developers to test and improve new calculation and
simulation tools
• The most reliable CFRP components suppliers including series manufacturing,
allowing us to adapt the component design to the proper manufacturing
technology.
09/05/2012 43
CASE STUDY: IR12 CHASSIS ANALYSIS Phase 1
cleanup&mesh
Hypermesh
Phase 2
materials&properties
Hyperview
HyperLaminate and
Laminate Tools Laminate Tools
Phase 3
post-processing
Phase 4
post-processing
09/05/2012 44
CASE STUDY:MODEL BUILD UP
09/05/2012 45
CASE STUDY: BOUNDARY CONDITIONS
Fixed at the engine
mountings
Load applied through
1D elements
09/05/2012 46
CASE STUDY: PLY-BY-PLY ANALYSIS
Lay-up
summary
Ply-by-ply stress tensors
Tsai-Wu
failure index
Tsai-Wu
reserve factor
09/05/2012 47
CASE STUDY:
DRAPING AND MANUFACTURING CONTROL
09/05/2012 48
PROVEN METHOD
• Fibre and resin definition (strength, stiffness, resin content)
• Experimental data from traction and compression tests on different
directions
• Creation of the FE model
• Definition of the composite material card
• Loadcases definition and analysis performing
• Analysis results validation by testing of complete or partial samples
09/05/2012 49
WHAT HAPPENS IN A DYNAMIC SCENARIO?
Dynamic Phenomena on CFRP
• Failure criteria
• Damages
• Failure propagation
• Inertial phenomena
• Instability
• Delamination
• Energy absorption
• Strain rate effect
09/05/2012 50
DYNAMIC SCENARIO: FIRST APPROACH
Dallara routine :
• Good correlation
• Simple geometry (i.e.: F1 crash box)
• No buckling
• No bending
09/05/2012 51
DYNAMIC SCENARIO: SECOND APPROACH
Material CARD
• 74 parameters
• Different failure theories
• Combination of different criteria
• Importance of the software house support
• Importance of being involved in the development
• Reliability of the software and of the testing laboratories
• Importance of the reasearch&development activities
09/05/2012 52
DALLARA AND ALTAIR
CRASH SIMULATION OF COMPOSITE STRUCTURES
• Altair and Dallara are working together to develop new tools for composite
structures crash simulation
• RADIOSS beta versions in use at Dallara
• Main focus = correlation between experimental data and simulation : broad Data
Base for both race cars and “super road cars”
• Design – simulate – make – test – correlate/validate : very fast “in house” process
Crash cone
09/05/2012 53
DALLARA AND ALTAIR
-
CASE STUDY: CRASH BOX STRUCTURE
09/05/2012 56
THE BEST SATISFACTION
“I've had a long and good relationship with Dallara. I
won the world's largest motor race, the Indianapolis
500 in one of their chassis. But performance is not
the only thing Dallara think about. They are also
extremely safetyconscious. I drove one of their
chassis when I had the biggest accident in my
career at Texas Motor Speedway, when my car was
launched into the barriers at 220 miles per hour
while battling for the podium in the latest stages of
the race. The g-force of the impact was measured
an incredible 214 g's, as the car virtually exploded
from the impact. It was highest the highest g-force to
be recorded in an impact, ever. But the safety cell
was intact. The sheer energy from the impact left me
severely injured and hospitalized for 3 months. It's
not in the nature of motorsports to be "bulletproof",
but I am convinced that it was thanks to Dallara's
innovation and safety thinking that I lived to race
another day”.
KENNY BRACK
Former Indianapolis 500 Champion
Kenny Brack