optimising full electric vehicle body in white architecture from a styling envelope
DESCRIPTION
This paper proposes an engineering process for optimising new Full Electrical Vehicle (FEV) lightweight vehicle architecture based upon OptiStruct topology optimisation, extracting the idealised load paths for a given set of load cases. Subsequently, shape and size optimisations (HyperStudy) are conducted in order to obtain detailed information of localised vehicle geometry, including automated 2D mesh generation from 1D beam models. The research discusses each individual step of the overall process including successes, limitations, and further engineering challenges and complications which will need to be resolved in order to automate the vehicle architecture design to include durability and (dynamic) crashworthiness performance.TRANSCRIPT
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 [email protected]
Christophe BastienPrincipal Lecturer Automotive EngineeringPrincipal Lecturer Automotive [email protected]
Mike V BlundellProfessor of Vehicle Dynamics & [email protected]