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:
Riske.Meijer@tno.nl
(Carmen.Rodarius@tno.nl)
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: riske.meijer@tno.nl
14
ORGANISATION TNO
| Carmen Rodarius
| WP N°2
| 12-13-14/04/2010