TEG th May th Flex-TEG Meeting JAMA/JARI

Transcription

1 TEG th May 29 8th Flex-TEG Meeting JAMA/JARI Development of a FE model and Analysis of the Correlation between the Flex- GTR-prototype and Human Lower Limb Outputs using Computer Simulation Models

2 Back Grounds was developed in Nov. 28. and its previous version, Flex-GT, are not exactly the same (e.g. knee joint construction). It is therefore required to reanalyze the correlation between the Flex-GTRprototype and Human lower limb. JAMA/JARI therefore developed a FE model, and then analyzed the correlation between the and Human Lower Limb outputs using computer simulation models.

3 Development of a model

4 and Developed FE model (Overview) FE Model Femur (Flexible) Femur (Flexible) Knee (Ligament restraint system) Knee (Ligament restraint system) Tibia (Flexible) Tibia (Flexible) Main body Flesh Main body Flesh

5 Femur bone core 3-point bending validation Test setup for Femur bone core 3-point bending validation F c : Force Center (N), D c : Deflection Center (mm) M c : Moment Center (Nm) = F C /2 (N) x.165 (m) Knee side of Femur bone core (fixed) Ram F c (Surface shape: r = 25 mm) 12 mm 12 mm Femur-1B Femur-2B Femur-3B Fc/2 65 mm Load transducer (type: KYOWA LU-1TE) Femur-1A Femur-2A Femur-3A 145 mm 165 mm 165 mm 15 mm Quasi static V = 8 mm/min Fc/2 (fixed) Length: 33 mm Model setup for Femur bone core 3-point bending validation Ram (rigid) 35 3 Femur bone core (rigid) (rigid) Moment center Mc (Nm) Corridor center Corridor U Corridor L model Deflection center D c (mm)

6 Tibia bone core 3-point bending validation Test setup for Tibia bone core 3-point bending validation F c : Force Center (N), D c : Deflection Center (mm) M c : Moment Center (Nm) = F C /2 (N) x.25 (m) Knee side of tibia bone core (fixed) Ram F c (Surface shape: r = 25 mm) 12 mm 12 mm Tibia-1B Tibia-2B Tibia-3B Tibia-4B Fc/2 Load transducer (type: KYOWA LU-1TE) Tibia-1A Tibia-2A Tibia-3A Tibia-4A 65 mm 15 mm 145 mm 185 mm 25 mm 25 mm Length: 41 mm Quasi static V = 8 mm/min Fc/2 (fixed) Model setup for Tibia bone core 3-point bending validation Ram (rigid) 35 3 Tibia bone core (rigid) (rigid) Moment center Mc (Nm) Corridor center Corridor U Corridor L model Deflection center D c (mm)

7 Femur 3-point bending validation Test setup for Femur 3-point bending validation F c : Force Center (N) M c : Moment Center (Nm) = F C /2 (N) x.165 (m) D c : Deflection Center (mm) Neoprene Load transducer (type: KYOWA LU-1TE) F c Ram (flat surface, φ = 4 mm) 5 mm Quasi static V = 8 mm/min Knee side of femur Femur-1B Femur-2B Femur-3B Femur-1A Femur-2A Femur-3A (rotate) (rotate) Rigid base Fc/2 165 mm 165 mm Fc/2 Length: 33 mm Model setup for Femur 3-point bending validation Ram (rigid) 35 3 Femur (rigid) (rigid) Moment center Mc (Nm) Corridor center Corridor U Corridor L model Deflection center D c (mm)

8 Tibia 3-point bending validation Test setup for Tibia 3-point bending validation F c : Force Center (N) M c : Moment Center (Nm) = F C /2 (N) x.25 (m) D c : Deflection Center (mm) Neoprene Load transducer (type: KYOWA LU-1TE) F c Ram (flat surface, φ = 4 mm) 5 mm Quasi static V = 8 mm/min Knee side of tibia Tibia-1B Tibia-2B Tibia-3B Tibia-4B Tibia-1A Tibia-2A Tibia-3A Tibia-4A (rotate) (rotate) Rigid base Fc/2 25 mm 25 mm Length: 41 mm Fc/2 Model setup for Tibia 3-point bending validation Ram (rigid) 35 3 Tibia (rigid) (rigid) Moment center Mc (Nm) Corridor center Corridor U Corridor L model Deflection center D c (mm)

9 Knee 3-point bending validation Test setup for Knee 3-point bending validation F c : Force Center - at Knee joint surface (N) = F 1 (N) + F 2 (N) M c : Moment Center - at Knee joint surface (Nm) = F 1 (N) x.2 (m) D c : Deflection Center (mm) Ram (r = 5 mm) F c Quasi static V = 5 mm/min Proximal end of knee Moment center Mc (Nm) MCL (rotate) (fixed) Load transducer (F 2 ) (type: KYOWA M4AL2-2TP-P) 5 mm 2 mm ACL PCL LCL PCL ACL MCL Length: 4 mm Model setup for Knee 3-point bending validation Ram (rigid) Neoprene (fixed) 2 mm Load transducer (F 1 ) (type: KYOWA M4AL2-2TP-P) (rotate) Rigid base ACL elongation (mm) MCL elongation (mm) ACL Force center Fc (N) (rigid) (rigid) PCL Corridor center Corridor U Corridor L model PCL elongation (mm) Force center Fc (N)

10 -2 Overall validation under the Simplified Car Impact Test setup for Simplified car validation Impact Speed: 11.1 m/s Experiment Experiment +1% Experiment -1% model 4 3 Tibia Femur Knee-ACL Simplified car Bending moment (Nm) Bending moment (Nm) ACL elongation (mm) Tibia Femur Knee-PCL Bending moment (Nm) 2 1 Bending moment (Nm) 2 1 PCL elongation (mm) 1 5 Model setup for Simplified car validation model Tibia Femur Knee-MCL Bending moment (Nm) 2 1 Bending moment (Nm) 2 1 MCL elongation (mm) Simplified car model 4 3 Tibia Knee-Acc Knee-LCL Bending moment (Nm) 2 1 Knee acceleration (m/s 2 ) LCL elongation (mm)

11 Analysis of Correlation between the and Human Lower Limb outputs using Computer Simulation Models

12 Computer simulation models Simplified car models: 18 cars (S1-S18, ESV 27, Paper Number 7-178) Lower Bumper Reference Height (LBRH): 215 mm mm 2 18 Impact Speed: 11.1 m/s Human model "extended rubber" model Vertical (mm) model Simplified car models (S1-S18) 6 4 BP (bumper) BLE (bonnet leading edge) 2 H I : base + 5 mm (75 mm) H I : base (25 mm) SP (spoiler) Horizontal (mm) H I : Impact height

13 models model "extended rubber" model Impact Side Impact Side model has similar constructions of an actual one. "extended rubber" model has improved structure of flesh. Rubber is extended to a Tibia bottom end. (Based on BASt/BGS proposal) Extended rubber Tibia bottom end

14 Flex-GTR prototype model 5 Tibia-Max. 5 Knee-MCL Model Tibia Bending Moment Max.-abs.- (Nm) Model Tibia Bending Moment Max.-abs.- (Nm) Human Model, Tibia Bending Moment, Max.-abs.- (Nm) y =.9835x (R tibia =.78) y = 1.259x (R tibia =.9) Model Knee MCL Elongation Max. (mm) Model Knee MCL Elongation Max. (mm) Human Model, Knee MCL Elongation, Max. (mm) Flex-GTR prototype "extended rubber" model Tibia-Max Knee-MCL y =.5751x (R MCL =.6) y =.5584x (R MCL =.55) Flex-GTR prototype model and Flex-GTR prototype "extended rubber" model show a high correlation with the human model. Correlation of Tibia- Max.(R tibia ): Flex-GTR prototype "extended rubber" model is higher than Flex-GTR prototype model. Correlation of Knee- MCL(R MCL ): Flex-GTR prototype "extended rubber" model and Flex- GTR prototype model is comparable Human Model, Tibia Bending Moment, Max.-abs.- (Nm) Human Model, Knee MCL Elongation, Max. (mm)

15 Flex-GTR prototype model Model Tibia Bending Moment Max.-abs.- (Nm) Tibia-Max. S12 S6 y =.9835x (R tibia =.78) LBRH: 215 mm LBRH: 235 mm LBRH: 315 mm S6 (LBRH: 215 mm) BLE BP SP S12 (LBRH: 215 mm) BLE BP SP Human Model, Tibia Bending Moment, Max.-abs.- (Nm) Flex-GTR prototype "extended rubber" model In case of that the Car spoiler height is low, discontinuous part of rubber Impact to the Car spoiler. Load to tibia become higher compare to the human one. Model Tibia Bending Moment Max.-abs.- (Nm) Tibia-Max. y = 1.259x (R tibia =.9) LBRH: 215 mm LBRH: 235 mm LBRH: 315 mm S6 (LBRH: 215 mm) BLE BP SP S12 (LBRH: 215 mm) BLE BP SP Human Model, Tibia Bending Moment, Max.-abs.- (Nm) Continuous part of rubber Load to tibia become comparable to the human one.

16 Conclusions Well validated FE model was developed in this study. When we analyzed the correlation between the and Human Lower Limb outputs, we obtained following findings,! Flex-GTR prototype model outputs show a high correlation with the human lower limb outputs.! Besides, in order to extend the rubber of the flesh to the tibia bottom shows higher correlation with human lower limb especially for the Tibia outputs. Correlation of Tibia (R tibia ): Flex-GTR prototype "extended rubber" model is higher than Flex-GTR prototype model. Correlation of Knee-MCL (R MCL ): Flex-GTR prototype "extended rubber" model and Flex-GTR prototype model is comparable. In order to obtain higher correlation between the Flex-GTRprototype and Human Lower Limb outputs, JAMA-JARI recommend to extend the Rubber sheets of the Flesh of Flex-PLI until to the bottom of Tibia.