Optimising FEV BIW Architecture from a Styling EnvelopeJesper ChristensenJesper Christensen

Coventry University, UK

Agenda

• Introduction

• Purpose & proposed methodology

• Topology optimisation

• Lessons learnt

• Crash structure and safety cell

• “Automation”

• Shape & size optimisation

• Crash structure development

• Safety cell development

• “Automation”

• Conclusion and future steps

• Low Carbon Vehicle Technology Project, ongoing TARF

• £29 million research project

• Project partners:

Introduction

Define a methodology for developing a

lightweight vehicle architecture (BIW)

Purpose & proposed methodology

• Define a methodology for developing a lightweight a rchitecture

• Requirements:

• Vehicle may be Fully Electric (FE) or Hybrid Electric (HE)

• How?

• “Conventional” BIW development

• Optimising “pre-existing” BIW 1.CAD model (design envelope)• Optimising “pre-existing” BIW

• Blank sheet � use optimisation1.CAD model (design envelope)

2.Topology optimisation

3.Shape- & size optimisation

4.BIW draft

Overall aims:

� Minimise BIW mass

� Meet safety requirements

Topology optimisation

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

Topology optimisation

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

15-20 minutes / model

GUI – “Automatic” topology optimisation setup - tcl

Barrier Creation

Wheel and suspension

Auxiliary components

Constraints

15-20 minutes / model

30 seconds / model

Topology ���� Shape- & size optimisation

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

Safety cell

Shape- & size optimisation

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

Shape- & size optimisation

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

Crash structure` Crash structure

BIW draft

1. CAD model (design envelope)

2. Topology optimisation

3. Shape- & size optimisation

4. BIW draft

Crash structure Safety cell

BIW draft

Conclusion and future steps

1.CAD model (design envelope)

2.Topology optimisation

3.Shape- & size optimisation

Conclusions:

� Good for (rapid) initial BIW load path estimations� Good for safety cell development� Inertia Relief� Limitations of linear elastic software� Interpretations of results are vital� HM tcl scripting enables rapid model setup

4.BIW draft� HM tcl scripting enables rapid model setup

Future steps:

� Non-linear topology optimisation (ESLM?)� Joint modelling (multiple materials)� Increased consideration of manufacturing constraints� Consideration of shape- and size opt. within topology opt.� Combined linear and non-linear topology optimisation

Conclusion and future steps

1.CAD model (design envelope)

2.Topology optimisation

3.Shape- & size optimisation

Conclusions:

� Interpretations of results are vital

4.BIW draftFuture steps:

� “Automatic” / mathematical extraction of results � CAD model

Conclusion and future steps

1.CAD model (design envelope)

2.Topology optimisation

3.Shape- & size optimisation

Conclusions:

� Excellent for lightweight crash structure development � Robust, stable and efficient response surfaces� Excellent coupling with Dynamic modelling� Excellent sampling point options

4.BIW draftFuture steps:

� “Automation” / template building (as topology setup)� “Direct link” with topology optimisation

Thank you for your attention – any questions?

Jesper Christensen Lecturer in Stress Analysisaa8867@coventry.ac.uk

Christophe BastienPrincipal Lecturer Automotive EngineeringPrincipal Lecturer Automotive Engineeringaa3425@coventry.ac.uk

Mike V BlundellProfessor of Vehicle Dynamics & Impactcex403@coventry.ac.uk