7_MBS 6WO and 6MO
Transcription
7_MBS 6WO and 6MO
CASPER TNO 6w and 6m old child human body model COVER Workshop | 13-14-15 March 2012 TUB – Berlin - Germany Carmen Rodarius, Riske Meijer, Cees Huijskens, TNO CASPER CASPER TNO tasks within CASPER Within the CASPER project, TNO performed the following tasks: • Literature survey on child and dummy developments • Development of a 6 week and 6 month old child human body model • Development of a accident reconstruction methodology using full body models 2 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER TNO tasks within CASPER Within the CASPER project, TNO performed the following tasks: • Literature survey on child and dummy developments • Development of a 6 week and 6 month old child human body model • Development of a accident reconstruction methodology using full body models 3 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Development of a 6 w and 6 m old child human body model • Code: MAYDMO Multibody models • Anthropometry for both models based on Candat data (same database as used for Q-dummy development) Geometric measure 6 weeks 6 months weight 4.85 kg 7.60 kg Standing height 566 mm 668 mm Seated height 394 mm 443 mm Neck circumference 212 mm 216 mm Head length 136 mm 152 mm Head breadth 104 mm 116 mm Head to chin height 136 mm 145 mm 4 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Development of a 6 w and 6 m old child human body model • Step one: scaling down from standard 50th percentile male human body model First draft of 6 months old MB human body model Standard 50th percentile MB human body model 5 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Development of a 6 w and 6 m old child human body model • Step 2: Refinement of outer geometry from adult to improved baby-like proportions 6 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Development of a 6 w and 6 m old child human body model • Step 3: Improving robustness and checking feasibility of kinematics • Step 4: Model validation (not done due to lack of data and time) 7 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Step 3: Robustness of models • Two multi-body baby models developed in MADYMO: – • Robustness tested by frontal, side and rear impact simulation with triangular pulse with 27 G peak, 150 ms duration. Also, literature study on material properties and injury limits of head, neck and thorax, and on suitable validation data. 8 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Accident reconstruction methodology Objectives (main activities) •Simulation of an ECE/R.44 dynamic validation test with “best practice” CRS & Q-dummy model. •Simulation of the selected accident scenario with a CRS-human body-vehicle input model developed in accordance with the required reference data from CASPER WP2 & 3. •Comparison between different simulation results and physical tests. Important questions: •Do we not know child’s pose right before the impact? •What are the typical research variables and what are the typical constraints? •How are robustness and reliability assessments included? •What will happen with the performance of the CRS if certain parameters change (e.g. ageing of material, belt slack, position of the CRS) or other scenarios are tested? 9 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Accident reconstruction methodology General Approach Model Creation Selection of accident scenario and reference regulatory Physical tests of selected components -Ad I: Selection of P or Qdummy -Ad II: Seat chushion stiffness test -Ad III: ECE/R.44 performance test 2 Simulation of physical tests based on ECE/R.44 reference test (senssitivity analysis) 3 Vehicle - CRS model creation -Belt restraint model (type of retractor) -Seat model (front seat or rear seat bench) -Group 0 CRS model 1 -sub-assembly -component -parts -sampels ECE/R.44 - CRS model creation -Belt restraint model (standard) -Seatbench model (standard) -Group 0 CRS model Procedures Simulation of selected accident scenario based on WP3 reference data (predicting trends) 6 Outcome: Technology and guidelines for quality modelling and simulation 9 Comparison of simulation results to experiments 5 Definition of validation criteria sets 4 (adapted for each human baby model) ad I: Injury Reference Values ad II: Proposed EEVC Criteria Outcome: Procedure and criteria for product certification Reference Data Dummy Model Validation 7 Human Body Model Validation 8 Outcome: Procedure and criteria for accident model validation Simulation Methodology 10 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Accident reconstruction methodology Pro’s based on proposed VT method: •Virtual testing is a useful method to investigate the types of crash conditions/scenarios that may occur in the field today. •With simulation models available for different accident scenarios, it is possible to pose “what-if questions” related to relevant vehicle-child restraint integration issues. Con’s based on proposed method: •The input to the restraint system (acceleration pulse) is not exactly the one produced by body structure. •The input is imposed and fixed, regardless of restraint system changes, while body pulse is subjected to some variation if restraint equipment has different characteristics (Differences between the real accident and a virtual reconstruction) 11 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Accident reconstruction methodology Discussion on possible outcomes/results: •The proposed VT method is able to predict only trends in most cases where no CRS-airbag interactions were observed. •Input from accident reconstruction data is subject to many sources of uncertainty including errors of measurement, absence of information and poor or partial understanding of the driving forces and mechanisms during an accident •Good modeling practice requires that the researcher/engineer provides an evaluation of the confidence in the model (sensitivity analysis) 12 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER Thank you very much for your kind attention! Contact: [email protected] ([email protected]) 13 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010 CASPER CASPER WP2.3: 6 weeks and 6 month old baby models The MADYMO baby models can be provided: - To CASPER partners for internal research or research with one or more of the other CASPER partners. - When CASPER partner has MADYMO tokens or MADYMO solver, XMadgic and Human Occupant Models license in order to be able to run the models. The MADYMO baby models are not available for: - Others, because we think the models are not sufficiently biofidelic due to lack of data of babies. - For commercial research. No support on the use of the baby models. However, there is a possibility for a co-development contract to further develop the MADYMO baby models with our support and free MADYMO licences. Contact: [email protected] 14 ORGANISATION TNO | Carmen Rodarius | WP N°2 | 12-13-14/04/2010