Body Structure & Chassis Optimization

Body Structure & Chassis Optimization

For Improving Driving Maneuvers

2011 European Hyperworks Technology Conference – Bonn

Dipl.-Ing. Elmar Teipen Dr.-Ing. Michel Paas R&A – Global Vehicle Dynamics Ford of Europe – Body Engineering

Dipl.-Ing. Hessel van Dijk Dr.-Ing. Axel Hänschke Ford of Europe – Body Engineering Ford of Europe – Analytical Prototype

Dipl.-Ing. Elmar Teipen – Global Vehicle Dynamics

Dipl.-Ing. Hessel van Dijk – Body Engineering Europe

2011 European Hyperworks Technology Conference - Bonn

Nov 8th, 2011 Page 2

• Why Body Structure Is Important To Vehicle Dynamics

• What Is The Body Doing During Driving ?

• How To Investigate Structural Performance For VD ?

• Customized Hyperstudy Approach

• MDO Application Examples

• Summary & Next Steps

Page 2

Agenda





Why Body Structure Is Important To Vehicle Dynamics

Steering

– Straight Ahead Controllability (On-Center) Compliance

Response: Amount, Linearity, Delay

Steering Wheel Torque Feedback

Modulation (Torque vs. Response)

Ride

– Primary Ride Control / Comfort

– Secondary Ride Shake

Rolling Feel / Plushness

– Impacts

Solidity / Rigidity / Quality Impression

Vehicle Dynamics Performance Influenced By Structural Stiffness & Weight





What Is The Body Doing During Driving ?

– Front End Lateral Bending

On-Center Compliance

Steering Precision

Response Delay, Non-Linearity

– Torsion

Front-to-Rear Balance

Compliance

Body Shake, S&R, Rigidity Feel

– Vertical Bending

Impact Harshness

Front End Shake, (S&R)

Trade-Off : Body / Chassis Lightweight Vehicle Dynamics Performance

Front End Lateral Bending.avi

Rear End Torsion.avi

Subframe.avi




Nov 8th, 2011 Page 5 Page 5

How To Investigate Structural Performance For VD ?

Hypermesh

Preprocessing

Competitor SW

MNF-Creation

Hyperworks

Postprocessing

Time-Consuming – Manual Interactions – Limited Variations – Not Efficient

- ADAMS/Chassis: MBS Pre-Processing (With Vehicle Templates) & Solving

- Embedded FE-Structures Of Body, Subframes, etc.

» Manual Hypermesh Preparation (Superelements, Interface Nodes, ...)

» Modal Reduction With Competitor Software On HPC Supercomputer

» Sequential MNF-Creation: Up To 3 h Per Run / Up To 16 GB mnf To Transfer

» Implementation With Python-Templates (Manually Edited)

- Hyperworks: VD Postprocessing (Based On Maneuver-Dependent Reports)

- Body & Chassis Structural Modifications Based On Individual Results

ADAMS/Chassis

Solving

HPC Local EWS Local EWS





Customized Hyperstudy Approach

TCL-Templates

Preprocessing

Radioss

MNF-Creation

ADAMS/Chassis

Solving

TCL-Templates

Postprocessing

- Hyperstudy Customized Integration:

» Selection Of Design Variables (In FE And MBS Templates) User Friendly

» In-The-Loop Generation / Calculation Of Combined Models Automated Pre+Post

» Fully Automated DOE Control From Local EWS No Manual Interaction

» Data-Intensive Work Completely On HPC Supercomputer Reduced File Transfer

» Semi-Parallel Runs Possible Reduced Run Time

» Collection Of Final Results (Some kB Per Run) On EWS Reduced Data

» Optimized License Application Reduced Cost

HPC

Customized Hyperstudy = Key Enabler For Statistical FE + MBS Analysis on HPC

Customized

Hyperstudy

Control & PP





– BIP content within a Trimmed Body + Subframes

– Design Variables: Sheet Thicknesses + ADAMS Bushings

– Generic Responses » Wheel Loads (nominal, min, max)

» Full Vehicle properties

» Frt Axle Load, Total Weight

– Stepsteer Responses (Time Domain): » Peak Yaw Rate, Peak LatAcc

» Steady-State LatAcc, Sideslip Angle, ...

– 4-Poster Responses (Frequency Domain): » 50 PSDs (each 1 – 30 Hz)

(Tpmnts, Seatrails, FrtBending, FulTors, Engine,...)

– Total Time To Complete: 2 Days (1000 Runs)

Customized HS : Complete In-/Output Matrix

Application Examples: Stepsteer & Ride 4-Poster

Vehicle Dynamics Attribute Requirements In Body / Chassis Lightweight MDO

Vehicle Dynamics Metrics vs. Sheets - Steering (Sinesteer, Stepsteer, On-Center)

- Ride (4-Poster, Road 10 Old Part, Blauwe Kei)

- Handling

- Braking

ride_labeled.avi





Data Mining

Optimization

Meta

Modelling

Validation

Correlations Clustering Analysis CART HyperStudy DOE

MDO Approach




Optimization


Data Mining

Meta

Modelling

Validation

HyperStudy DOE

MDO Approach

sampleMM_labeled.avi




Optimization


Data Mining

Meta

Modelling

Validation

HyperStudy DOE

MDO Approach

samplePF_labeled.avi





Data Mining

Meta

Modelling

Validation

HyperStudy DOE

HyperStudy

MDO Approach

Optimization





Application Example: Body Impact @ Full Vehicle Ride F

V F

req

ue

nc

y R

es

po

ns

es

: R

ide

Body DVs

Zo

om

: F

ull

To

rsio

n (

1 –

30

Hz)

Design Variables

Data-Mining





MDO Toolkit Example: Frequency-Dependent Correlations

MDO Toolkit Available To Visualize Structural Effects Against Full Vehicle Metrics

Body DVs

FV Response Data-Mining

Significant_Parts_11_labeled.avi





1. Total Mass

2. Stat. Stiffness

3. Dyn. Stiffness

4. Modes /Tors. Stiffn.

5. EUNCAP ODB

6. Rear Impact

7. LINCAP

Meta Models incl. constraint eqs. DVs RVs

Meta

Modelling &

Optimization

MDO Subcase Extension

Additional VD Loadcases To MDO Process = X-Attribute Trade-Off Studies

+

8. Vehicle Dynamics / Steering

9. Vehicle Dynamics / Ride

+





Summary

Page 15

• Vehicle Dynamics Attribute Significantly Influenced By Structural Stiffness & Weight

• Lightweight Trend: Potentials & Risks For Vehicle Dynamics

• Standard Process Inefficient To Systematically Investigate Trade-Offs

• Customized Hyperstudy Enables X-Attribute MDO Including Vehicle Dynamics

– From Manual Iterations To Automatic Process

– From Local EWS To Supercomputer

– From Competitor Software To Radioss

– From Single Attribute Optimization To X-Attribute MDO

Next Steps

• Process Refinements

• Implementation Of Structural Concepts





Contacts

Elmar Teipen Dr. Michel Paas

+49 (0)221 9034526 +49 (0)221 9037755

[email protected] [email protected]

Hessel van Dijk Dr. Axel Hänschke

+49 (0)221 9036333 +49 (0)221 9033441

[email protected] [email protected]

Special Thanks …

• Axel Flick, Altair Office Cologne

• Alexander Koch, Altair Office Cologne

• Thomas Kowalewski, Altair Office Cologne

• Arno Klein, P+Z Engineering

• Matthias Stenkamp, P+Z Engineering

mailto:[email protected]




Thank you for your attention !


