Correlation of Simulation Models using Concept Modeling

Correlation of Simulation Models
using Concept Modeling
Dr. Jörgen Hilmann, Joe Abramczyk
Dr. Salvatore Scalera
Andreas Arlt
Ford Motor Company
RLE International
SFE GmbH Berlin
Correlation of Simulation Models using Concept Modeling
Dr. Jörgen Hilmann, Joe Abramczyk, Ford Motor Company
Dr. Salvatore Scalera, RLE International; Andreas Arlt, SFE GmbH Berlin
Keywords: RADIOSS, HyperMesh, MotionView, SFE Concept, Correlation, Front Impact, Side Impact
ABSTRACT
Pre-requisite for efficient vehicle programs is the CAE driven development process as described in [1], [2] "Up Front CAE". Both CAD and CAE models
based on special Concept Software as SFE CONCEPT are used to analyze the attribute performance as safety, NVH or durability and commodity studies
concerning the weight, manufacturing, or package. A database of concept models is used to minimize the modeling effort and to maximize the re-usability of
components [3]. The accuracy of the models increases over time and leads to an increasing amount of available Concept models in databases. Due to the
increased acceleration of the development process, these models are critical in providing direction on vehicle architecture in the early stages of a program.
Due to the high importance of these decisions it is mandatory to trust the results of this early CAE models. Correlation of this Concept models to test or
reference mainstream CAE models creates the confidence in this approach. The correlation focuses on two aspects: 1. the level of detail required to capture
the detailed folding characteristic of the structure (e.g. siderail or B-Pillar) and 2. the process chain used to process the raw output from SFE Concept into
RADIOSS Include files (e.g. gap, contacts, spot-welding, adhesives, bolts). This process chain is implemented using HyperMesh in batch mode, details may
be found in [4]. This process chain is tuned to latest program modeling approaches and to meet the desired correlation status.
In this presentation RADIOSS safety concept models are correlated to different impact modes. Tools and methods are explained focusing on both the
automated evaluation of simulation output and the judgment of the correlation quality. The main criteria defining the correlation fitness are video overlay of
vehicle and dummies kinematics, curve comparison of vehicles acceleration, velocity, and intrusion. Furthermore the dummy sensors have been evaluated.
The combination of the above mentioned steps enable an accelerated and more confident concept phase allowing for more alternatives being analyzed in a
more holistic and detailed manner as described in [5], [3]. This is a pre-requisite for the creation of efficient designs under the constraints of an increasingly
accelerated development process.
BIBLIOGRAPHY
[1] E. Schelkle and H. Elsenhans,
"Virtual Vehicle Development in the Concept Stage – Current Status of CAE and Outlook on the Future", 3rd MSC Worldwide Aerospace
Conference & Technology Showcase in Toulouse 2001
[2] Jörgen Hilmann (Ford) und Uwe Wagner (Ford),
„CAE driven development process for the early vehicle development phase.“ IABC Confernce 2007 in Berlin
[3] Michael Keimes, Dr. Jörgen Hilmann, Martin Lichter, Dr. Uwe Wagner,
"Optimierungsstrategien für Leichtbauprojekte" VDI Leichtbaukonfernz Ludwigsburg, 2011.
[4] Jörgen Hilmann (Ford) und Hans Zimmer (SFE GmbH)
„Development and application of an automated model built process chain for the Preprogram and Concept phase using SFE CONCEPT and the Altair
Hyperworks package.“ EHTC Konferenz in Strassbourg 2008
[5] K.H. Volz and H.Zimmer,
"Optimizing Topology and Shape for Crashworthiness in Vehicle Product Development", IABC Confernce 2007 in Berlin
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation of Simulation Models using Concept Modeling
Contents
•
•
•
•
Introduction
Motivation for Concept Modeling
Concept Models & Libraries
Model built and Include Files
•
•
•
Correlation quality: Procedure and Criteria
Vehicle Samples
Q&A
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Introduction
Basic Design
… is a Mini Product Development Department
Project Lead
B-Car
Project Lead
C-Car
Project Lead
CD-Car
Body Exterior
Body
Body Interior &
Attributes
Electrical
Chassis
Veh. Dyn.
…
Electrical
Chassis & Veh.Dyn.
SQ & V (NVH)
Concepts
Vehicle Integration
Link
to “LHS“
Powertrain Integration
Mechanical Package
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Total Basic Design Team
with Matrix Organization
- Technical Specialists
- Supervisors
- Base heads
- Contractors
Project Lead
Commercial
Separate CAE Attribute Workstreams – OLD State
Model Quality
Update Effort for each attribute & Risk for misaligned program assumptions
Dev. Time
Safety
Upda
te1
Pre
decessor
Update
2
Update 3
Update n
NVH
Pre-decessor
Update
b
Update
c
Update
x
Durability
Predece
ssor
Update
I
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Update
II
Concept Modeling in CAE driven development process
Usage of Concept Module Libraries & Standardized Pre-Processing Procedure & Include Assembly Process
• Concept libraries are populated during
the concept modeling work
Concept module library
• Re-use of concept modules increases over time
driven through best practice initiatives
e.g. for joint execution or Pillar designs
• A process chain is implemented using
Altair Hypermesh processing re-occurring
pre-processing tasks in automated batch mode
• The full vehicle models are assembled from different
sources using the RADIOSS Include files:
- Correlated CAE models / modules from the
mainstream development teams
- Parts / Modules developed in the concept modeling
department using e.g. SFE Concept
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Process Chain
meshing, using
HyperWorks package
in batch mode
RADIOSS
Include
Assembly
Process
Integrated CAE Attribute Workstreams – Current State
Model Quality
Update Effort shared among the team & No risk for misaligned program assumptions
Dev. Time
Baseline study
Component studies
Pre
decessor
Virtual design verification
Concept development
& Iterations
New model
VCS 1 Level
Safety NVH
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
model update
VCS 2 level
Safety
NVH
model update
VCS 3 Level
Durability
Safety NVH Durability
Price of the new process: Demand for Correlation
Starting the work from correlated reference models does not require up front preparation
• In order to built CAE concept model
confidence it is mandatory to verify the
predictive power of CAE Concept models
using correlation studies.
Concept module
• Herein the full vehicle models (including the
concept modules) reflect the <Job #1>
design intent of the pre-decessor model.
• The Correlation-Phase is used to familiarize
the team with the new program and to
ensure the processes used are capable.
• Two Objectives for Correlation:
1. Geometry and Mesh level of detail
2. Process to built the full vehicle model
Modules from the reference model
Correlated reference CAE Model
Substitution of concept modules
Correlation of the new model
Analysis of concept alternatives
using the same processes
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation types
Starting the work from correlated reference models does not require up front preparation
Difficult to standardize the correlation approach,
due to differentiation through:
• Application to geometry or the model built process chain; or both.
• Applied Car Line: B-CAR / C-CAR / CD-CAR / Light Commercial Vehicles
• Availability of reference data: Mainstream CAE and/or real test results
• Different Impact Modes: Front, Side, Rear, …
• Different Requirements / Markets
As a consequence the correlation task is challenging and
the required timing difficult to predict.
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Required accuracy of the model
The Level of detail is a function of the impact mode and
FORD FOCUS
SFE Concept Geometry
SFE Concept FE Mesh
Within Ford concept models
using the same numerical code,
e.g. RADIOSS for Safety analysis.
Mainstream CAE
The level of detail ranges between both:
- A rough box section to represent an inertia effect of structure, which
is not considered to deform
- A detailed geometry with all holes and depressions if considered
being important e.g. under axial compression in a frontal impact.
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation Sample: Frontal Offset
Key take aways of this presentation
ODB – EuroNCAP Frontal Offset / IIHS
Model correlation status is satisfactory for:
• Siderail behavior
• Overall intrusion values
(although slight under-prediction of Toeboard intrusion)
• Crash pulse
This CAE model is w.r.t. the offset impact
well suited to support A to B comparisons
of architecture studies
Reference model
--
--
--
Concept model
-14mm -1mm 2mm
delta to reference
-3mm
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
--
--
-6mm 2mm
ridedown area
CC_Beam
A_Point
Upper_Cowl
Cowl
Dashboard
Offset
Deformable
Barrier
64kph
ToeBoard
Displacement delta values
--3mm
Conventional
CAE model
Concept
model
Correlation Sample: Full Frontal Rigid Barrier
Key take aways of this presentation
Straight Front – US-NCAP, SDG
Model correlation status is overall satisfactory
but there is a minor difference in the siderail bending.
As a consequence the pulse shape show
a slight deviation.
Upper_Cowl
A_Point
CC_Beam
ridedown area
Concept model
Cowl
Reference model
Dashboard
Full Frontal
Rigid Barrier
56kph
ToeBoard
For A to B Comparisons may be used.
--
--
--
--
--
--
--
-12mm
-15mm
2mm
9mm
-3mm
2mm
-5mm
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Conventional
CAE model
Concept
model
Correlation Sample: Ford Mondeo Frontal Offset
Concept Upper Structure combined with mainstream residual modules
Dual Color Overlay: A to B comparison
Blue: Mondeo reference CAE model
Gold: Mondeo SFE CONCEPT Model
(with carry over parts e.g. Platform, PT,…)
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation Sample: Ford Mondeo Side Impact
Concept Upper Structure combined with mainstream residual modules
Blue: Mondeo reference CAE model
Gold: Mondeo SFE CONCEPT Model
(with carry over parts e.g. Platform, PT,…)
B-Pillar velocities
@
Striker
Door
velocities
@ Pelvis
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
B-Pillar velocities
@ B-Pillar-Mid
@ Thorax
Correlation Method: Film / CAE Overlay
Overlay of a physical Test Film with a RADIOSS Crash Simulation: High Speed barrier side impact
0 ms
50 ms
AVI
100 ms
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation Method: Curve comparison using channels
Overlay of a physical curve measurements with RADIOSS time history readings
Accelerometer readings
Black: CAE model
Gray: Test curves
Blue channel borders
B-pillar @
beltline
Black: CAE model
Gray: Test curves
Blue channel borders
A
B-pillar @
striker
A
B
B
C
Bpillar
@
rocker
Method:
Black: CAE model
Gray: Test curves
Blue channel borders
- Create the average curve of all test curves
- Add ±15% of the average peak of the curves to define a channel
Observation:
• The accelerations evaluated using CAE model are almost always
contained in the band fluctuation of real acceleration
C
• The peak of the B-pillar_@_rocker acceleration is slightly
underestimated
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Correlation Method: Peak curve comparison
Overlay of a physical curve measurements with RADIOSS time history readings
Normalization: The bar charts represent the max. injury criteria
divided by the arithmetic mean of available test max. injury criteria.
“1” being the average of the available test curve maxima for this criteria, e.g. HIC36
Test Variation: The CAE results (orange bar) are in the range of test values,
except the Pubic Load for the 1st row and Spine Acceleration in the 2nd row.
1,45
1st row
1,40
1,35
1,55
2nd row
1,50
1,45
1,30
1,40
1,25
1,35
1,30
1,20
1,25
1,15
1,20
1,10
1,15
1,05
1,10
1,00
1,05
0,95
1,00
0,90
0,95
0,85
0,90
0,80
0,85
0,75
0,80
0,75
0,70
0,70
0,65
0,65
0,60
0,60
0,55
0,55
0,50
0,50
0,45
0,45
0,40
0,40
0,35
0,35
0,30
0,30
0,25
0,25
0,20
0,20
0,15
0,15
0,10
0,10
0,05
0,05
0,00
0,00
Ave5RibDis [mm]
HIC36
MaxThoRib
Abdomen Force
Spine lowe
acceleration
Pelvis acceleration
Pubic Fy
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
HIC36
Shoulder deflection [mm]
T12 acceleration [g´s]
T1 acceleration [g´s]
Pelvis acceleration [g´s]
Iliac Fy
Acetabulum Fy
Conclusions
Key take aways of this presentation
•
•
•
•
•
Concept modeling significantly changed the vehicle development
towards a CAE driven Development Process,
however requires to built confidence in the used simulation models.
Demand for correlation!
Methods are presented using visual and statistical methods to determine
the correlation quality
These methods are objective and measurable; they help to be as
accurate as necessary to reflect the system behavior without capturing all
details of one single test result,
prevents the risk of overfitting / overpredicting to one test.
Having solutions for concept modeling, process chain and correlation
under control you can use this approach as a generic approach for
structure development.
Very helpful is the coupling with Topology Optimization e.g. Optistruct.
and the consideration of system noises Robustness.
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera, Andreas Arlt
Selecting the best Subsystems
A holistic Approach of Evolution & Revolution
SWOT
Architecture Study
Demands / Wishes
Topology Opt.
Altair Optistruct
• System xyz is not weight
efficient enough
• Demand to improve vehicle
Competitor
Evolution
“white Paper”
performance abc
Part F
Other
• Part t.b.d. is not package Reference
Predecessor Part D
Part B
Segment
model
efficient enough
Part E
Part A
Part C
Beam representation of
•…
the major Load Pathes
incl. Sensitivities
Concept development considering all available findings
?
Materialgaugeoptimization and
Materialgrade optimization
Safety
ODB/FF
NVH
Static / Dyn.
2011 European HyperWorks Technology Conference
Jörgen Hilmann, Joe Abramczyk, Salvatore Scalera Andreas Arlt
Weight
Thanks for your attention!
Correlation of Simulation Models using
Concept Modeling
Team of Authors:
Dr. Jörgen Hilmann, Joe Abramczyk
Dr. Salvatore Scalera
Andreas Arlt
Ford Motor Company
RLE International
SFE GmbH Berlin