ISEA Summer School – Prato 3 rd June 2005 # Marco Pierini Marco Pierini – Università di Firenze...
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Transcript of ISEA Summer School – Prato 3 rd June 2005 # Marco Pierini Marco Pierini – Università di Firenze...
ISEA Summer School – Prato 3rd June 2005 1
Marco Pierini Marco Pierini – Università di Firenze – Italy
FEM and Multibody Modelling of Luge Sled
ISEA Summer School – Prato 3rd June 2005 2
Cooperation UNIFI – FISI (Italian Federation for Cooperation UNIFI – FISI (Italian Federation for Winter Sports)Winter Sports)
• Started in 2000Started in 2000
• Aim: Make the Sled easier to driveAim: Make the Sled easier to drive
FASTERFASTER
ISEA Summer School – Prato 3rd June 2005 3
ObjectiveObjective
• Short period (Salt Lake City Olimpic games: 2002)Short period (Salt Lake City Olimpic games: 2002)
Small improvementSmall improvementSmall improvementSmall improvement
• Longer period (Torino Olimpic Games: 2006)Longer period (Torino Olimpic Games: 2006)
FEM and MB ModellingFEM and MB ModellingFEM and MB ModellingFEM and MB Modelling
ISEA Summer School – Prato 3rd June 2005 4
Open problemsOpen problems
•Very small know-how•Very small know-how
No publications on previous workNo publications on previous work
No previous experience in ItalyNo previous experience in Italy
•Translate in “engineering sense” the athlete sensation/feeling •Translate in “engineering sense” the athlete sensation/feeling
It has no sense to build a sled that the athlete dos not like!!!!It has no sense to build a sled that the athlete dos not like!!!!
ISEA Summer School – Prato 3rd June 2005 5
International Luge FederationInternational Luge Federation
natural tracknatural track artificial track artificial track
ISEA Summer School – Prato 3rd June 2005 6
DescentDescent
ISEA Summer School – Prato 3rd June 2005 7
Some rulesSome rules
• 21-25 kg for a single sled21-25 kg for a single sled
• ControlsControls– Temperature of the blades Temperature of the blades – Weight of the sled Weight of the sled – Overall weight of the athlete Overall weight of the athlete
• TrackTrack– Minimum length 1000 mMinimum length 1000 m– Maximum length 1300 mMaximum length 1300 m
ISEA Summer School – Prato 3rd June 2005 8
More Interesting FactsMore Interesting Facts
• Competitions may be held in extreme weather conditions Competitions may be held in extreme weather conditions with a temperature as low as – 25°Cwith a temperature as low as – 25°C
• If an athlete loses any item during a run he/she will be If an athlete loses any item during a run he/she will be disqualified disqualified
• The time is measured with an accuracy of 1000th of a The time is measured with an accuracy of 1000th of a second second
• In case of snowfall the track is swept after a certain number In case of snowfall the track is swept after a certain number of athletes of athletes
• The athlete has to pass the finish line in contact with The athlete has to pass the finish line in contact with his/her sled his/her sled
• In order to participate in a competition the athletes require In order to participate in a competition the athletes require a valid license (medical check-up, valid insurance) a valid license (medical check-up, valid insurance)
• The athlete must wear the FIL safety helmet The athlete must wear the FIL safety helmet
ISEA Summer School – Prato 3rd June 2005 9
The SledThe Sled
RuunersRuuners
SeatSeat
BridgesBridges
BladesBlades
ISEA Summer School – Prato 3rd June 2005 10
Seat (also called Pod Seat)Seat (also called Pod Seat)
ISEA Summer School – Prato 3rd June 2005 11
Front bridgeFront bridge
ISEA Summer School – Prato 3rd June 2005 12
M8M8
Ruuners and BladesRuuners and Blades
ISEA Summer School – Prato 3rd June 2005 13
Driving techniqueDriving technique
ISEA Summer School – Prato 3rd June 2005 14
Max Acceleration 6gMax Acceleration 6g
Driving techniqueDriving technique
Max Speed 140 km/hMax Speed 140 km/h
ISEA Summer School – Prato 3rd June 2005 15
Vertical & Transversal StiffnessVertical & Transversal Stiffness
Front ViewFront View
Vertical StiffnessVertical Stiffness
Rear ViewRear View
Transversal StiffnessTransversal Stiffness
ISEA Summer School – Prato 3rd June 2005 16
Short period improvementShort period improvement
• Possible variation Possible variation
in the sledin the sled
Keeping in mind the rules!!!!Keeping in mind the rules!!!!
Modify the stiffness to fulfill the requirement of different tracks
Modify the stiffness to fulfill the requirement of different tracks
• Screw torqueScrew torque• Silent-BlockSilent-Block
• Steel pullSteel pull
Reduction of vibration transmitted to the athlete
Reduction of vibration transmitted to the athlete
Increase transversal stiffnessIncrease transversal stiffness
ISEA Summer School – Prato 3rd June 2005 17
Position of the BridgesPosition of the Bridges
Different tickness of the bridgesDifferent tickness of the bridges
AimAim Change of the stiffness due to:Change of the stiffness due to:
Different Sled configuration (FEM)Different Sled configuration (FEM)
ForceForceWeightWeight
ISEA Summer School – Prato 3rd June 2005 18
Different Sled configuration (results)Different Sled configuration (results)
ISEA Summer School – Prato 3rd June 2005 19
Force Weigth
Original 9 405 11,1 0 0,60 0
Optimal 10 305 11,7 -5% 0,30 +52%
Modified 1 9 305
Distance between bridges [mm]
Bridges Tickness
0,63 +5%
UXmax
14,4 -30%
UY
Different Sled configuration (results)Different Sled configuration (results)
ISEA Summer School – Prato 3rd June 2005 20
Steel PullSteel Pull
AimAim Increase transversal StiffnessIncrease transversal Stiffness
ISEA Summer School – Prato 3rd June 2005 21
Traction testTraction test
Ultimate force 8000 N
Calculate (FEM) max Force 800 N
ISEA Summer School – Prato 3rd June 2005 22
Force Weigth
UY UXmax
Original 9 40511,1
00,600
0
With pull 9 4059.13
+18%0,114
+420%
Bridges Tickness
Distance between Bridges
[mm] [mm]
MOD3FILO1 7 40514,8 -33%
0,130 +360%
DIST305f 9 30512,4 -12%
0,131 +360%
Steel pullSteel pull
ISEA Summer School – Prato 3rd June 2005 23
Control of the torqueControl of the torque
M1=14 NmM1=14 Nm
M2=19 NmM2=19 Nm
M3=24 NmM3=24 Nm
ISEA Summer School – Prato 3rd June 2005 24
Control of the torque (results)Control of the torque (results)
Torque M2
Torque M1
ISEA Summer School – Prato 3rd June 2005 25
Silent-blockSilent-block
ISEA Summer School – Prato 3rd June 2005 26
Silent-blockSilent-block
ISEA Summer School – Prato 3rd June 2005 27
Silent-blockSilent-block
MassMass
Max AccelerationMax Acceleration
FEMFEM
Force acting on the Silent-blockForce acting on the Silent-block
N1470
4smg6kg100
F2
ISEA Summer School – Prato 3rd June 2005 28
Silent-block (results)Silent-block (results)
Configurationdeformation
[mm]difference
%Original 0,230 0
Buttonhole 0,357 55
5 holes 0,337 47
ISEA Summer School – Prato 3rd June 2005 29
Short period improvement Short period improvement
• Reverse engineering of the SledReverse engineering of the Sled
• Development of the MB-FEMDevelopment of the MB-FEM
Aim: development of MB-FEM model able to simulate the descentAim: development of MB-FEM model able to simulate the descent
StepsSteps
ISEA Summer School – Prato 3rd June 2005 30
CAD ModelCAD
Model
Reverse EngineeringReverse Engineering
Phisical Model
Phisical Model
ISEA Summer School – Prato 3rd June 2005 31
Reverse EngineeringReverse Engineering
InstrumentsInstruments
“FARO Arm”“FARO Arm”
CADCAD
Software “Anthrocam”Software “Anthrocam”
ISEA Summer School – Prato 3rd June 2005 32
Reverse EngineeringReverse Engineering
Very important to use the same reference systemVery important to use the same reference system
ISEA Summer School – Prato 3rd June 2005 33
• Scanning ModeScanning Mode
Reverse EngineeringReverse Engineering
• Point ModePoint Mode
Acquisition TechniquesAcquisition Techniques
CAD ModelCAD Model
ISEA Summer School – Prato 3rd June 2005 34
MB-FE ModelingMB-FE Modeling
• MSC Adams MSC Adams
Simplied modelSimplied model
Accurate modelAccurate model
ISEA Summer School – Prato 3rd June 2005 35
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied model
Made with rigid body elementMade with rigid body element
Ruuner + BladeRuuner + Blade
BridgesBridges
Center of gravity of athlete
Center of gravity of athlete
ISEA Summer School – Prato 3rd June 2005 36
MB-FE ModelingMB-FE Modeling
Interaction between solidInteraction between solid
Function “Contact”Function “Contact”
Simplied modelSimplied model
Simulation of contact and frictionSimulation of contact and friction
ISEA Summer School – Prato 3rd June 2005 37
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied model
Use of spheres for the contactUse of spheres for the contact
ISEA Summer School – Prato 3rd June 2005 38
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied model
FF
Seconda configurationSeconda configuration - No DOF
- No Friction
- Lateral Forces
- No DOF
- No Friction
- Lateral Forces
First configurationFirst configuration - 1 DOF
- Friction
- 1 DOF
- Friction
ISEA Summer School – Prato 3rd June 2005 39
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied model
)Fv1(LogkF CL
General Force: (Lateral Force)General Force: (Lateral Force)
ISEA Summer School – Prato 3rd June 2005 40
No lateral forcesNo lateral forces
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied model
ISEA Summer School – Prato 3rd June 2005 41
MB-FE ModelingMB-FE Modeling
Simplied modelSimplied modelWith lateral ForcesWith lateral Forces
ISEA Summer School – Prato 3rd June 2005 42
MB-FE ModelingMB-FE Modeling
Accurate modelAccurate model
Common characteristicsCommon characteristics
Inertial propertiesInertial properties
Silent-block are also modeledSilent-block are also modeled
All parts are geometrically correct and flexibleAll parts are geometrically correct and flexible
Spheres to simulate the contactSpheres to simulate the contact
Main differerencesMain differerences
Lateral ForcesLateral Forces
ISEA Summer School – Prato 3rd June 2005 43
MB-FE ModelingMB-FE Modeling
Accurate modelAccurate model
CAD ModelCAD Model
ParasolidParasolid
FEM modelFEM model
Flexible partsFlexible parts
ISEA Summer School – Prato 3rd June 2005 44
MB-FE ModelingMB-FE Modeling
Accurate modelAccurate model
Adams modelAdams model
ISEA Summer School – Prato 3rd June 2005 45
MB-FE ModelingMB-FE Modeling
Accurate modelAccurate modelFirst SimulationFirst Simulation
Entrance in the labyrinthEntrance in the labyrinth
ISEA Summer School – Prato 3rd June 2005 46
Second SimulationSecond Simulation
MB-FE ModelingMB-FE Modeling
Accurate modelAccurate model
Turn constant radiusTurn constant radius
ISEA Summer School – Prato 3rd June 2005 47
Salt Lake City Olympic Games 2002Salt Lake City Olympic Games 2002 Armin Zoeggeler. IV Run Armin Zoeggeler. IV Run
ISEA Summer School – Prato 3rd June 2005 48
Armin Zoeggeler
Gold Medal
Salt Lake City Olympic Games 2002
Armin Zoeggeler
Gold Medal
Salt Lake City Olympic Games 2002