1 JLR Proprietary A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover 2015 UK Altair Technology Conference Andrew Blows Technical Specialist - BCAE Strength & Durability [email protected]
Aug 15, 2015
1 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing
Systems at Land Rover
2015 UK Altair Technology Conference
Andrew Blows Technical Specialist - BCAE Strength & Durability [email protected]
3 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
4 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
5 JLR Proprietary
Product Attribute Leadership Strategy (PALS)
Level 1 Attributes
A0: Product Efficiency A1: Safety A2: Perceived Quality A3: Accommodation & Usage A4: Vehicle HMI & Audio-Visual Performance A5: Vehicle Dynamics A6: Braking A7: Performance & Driveability A8: Vehicle NVH & Sound Quality A9: Durability & Reliability A10: Off Road & All Road Capability A11: Weight A12: Environment & Energy Management A13: Service & Ownership A14: All Weather Comfort & Vision A15: TASE A16: Security
A9: Durability & Reliability Durability vehicle life Corrosion vehicle life Retained Newness Robustness and Strength
Trailer Towing
• Trailer towing - brand DNA for Land Rover Products
• Vehicle Performance – Categories into attributes
• Product Attribute Leadership Strategy (PALS) targets are used to define and compare Land Rover’s capability against competitors
• PALS targets - maintain the high quality experience expected by our customers
A9: Durability & Reliability Durability vehicle life Corrosion vehicle life Retained Newness Robustness and Strength
Trailer Towing
6 JLR Proprietary
Product Attribute Leadership Strategy (PALS)
PALS
Customer Duty Cycle Targets
Requirements
Competitor Benchmarking
CAE
Physical Test Methods
Bolted Joint
Road Load Data (RLD)
Trailer Towing Optimisation
Virtual RLD
Loads & Duty Cycles
Capability Growth Projects (CGP) /
Correlation / Methods
Trailer Towing
Material Neuber
CAE / Test Correlation
2013-022 2014-204a 2014-204b
7 JLR Proprietary
Trailer Towing CGP – 204 b Loads Project Plan
Different Categories of Vehicles Different Trailers Different surfaces at MIRA Proving Ground
Tow bar Loads
Virtual tool set for TPJLR.00.008 Assess the existing TPJLR.00.008 Input to Body CAE for towing kit optimization project Vehicle Tow bar loads
Different trailers Different Vehicles Different road surfaces
8 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
9 JLR Proprietary
System
Trailer Towing CAE
Inputs Signal
Force
Ideal Function Output
Force – Deflection - Life Plastic strain < X%
Permanent deformation < Ymm Fatigue > N Repeats of Test Residual Bolt Torque > T Nm
Control Factors •Towing Capacity & Nose Load. •Loading - magnitudes & directions •Loading - Duty Cycle •Materials - Monotonic •Materials - Cyclic/Fatigue •Bolt Torque Methods •Targets - Bolt slip capacities •CAE Modelling procedure's
Noise 1 Piece-to-Piece
•Bolt Torque Tolerance •Coefficient of Friction •Material Yield Stress •Thickness variation •Welding Distortion •Residual Clamp •Assembly tolerance
Noise 2 Change Over Time
•Mig Weld size •Change to Material Yield •Residual Torque •Assembly tolerance
Noise 4 External Environment •Pre-strain •Pre-stress
Noise 5 System Interaction
Error States/Failure Modes • Excessive deformation • Fatigue • Bolt Torque Relaxation • Mass over target • Complex assembly
Noise Factors
Inner Noise (Capacity) Outer Noise (Demand)
Trailer Towing Parameter-Diagram
Noise 3 Customer Usage
•Loading magnitude •Loading directions •Loading Duty Cycle •CAE Process issues •CAE Capability Rating
10 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
11 JLR Proprietary
Non-Linear Material in Linear Analysis
Neuber equivalent Plastic Strains = f (Stress)
Neuber equivalent
Plastic Strains
Stre
ss
Strain
Neuber Hyperbola
Neuber
Linear Elastic FEA Stress
12 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
13 JLR Proprietary
Systematic Flow
Topology Opt
Targets-Displacement Stress Plastic strain Slip Capacity
Package Space
Yield Stress
Material Grade Bolt :- No / Size / Position Neuber
Linear Model
Solid Load Paths
Initial Concept Design
Critical characteristics Loads
‘Key fact holders’
Not everything can be linearized
14 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
15 JLR Proprietary
Topology
Concept Strategy • Optimise a bad concept Or • Optimising a good concept • Identify features that are critical to success • Explore package conflicts • Resolve to lightest design solution
16 JLR Proprietary
Topology
Package Design Space
Topology Optimised design
Explored Design Space find optimised designed for different Ball Joint Offset to Longitudinal • Z - Ball height • X - Offset
Z
X
17 JLR Proprietary
Packing Design Tool – Mass change with Ball Joint Offset
Offset from CL of Longit.
Mass
Bas
elin
e
Pro
pose
d
Provide tools to enable fundamental dimension of system to be influenced in the early design process. Offset to Longitudinal • Z - Ball height • X - Offset
% change in Mass
• Provide critical characteristics to key fact holder • More informed decision making in concept phase
18 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
19 JLR Proprietary
Systematic Flow
Topology Opt
Targets-Displacement Stress Plastic strain Slip Capacity Fatigue
Bolt Joint Stiffness
Design Interpretation
Package Space
Yield Stress Material Grade Bolt :- No / Size / Position
Neuber
Linear Model
Solid
Shell
Load Paths
Initial Concept Design
Critical characteristics Loads
Not everything can be linearized
20 JLR Proprietary
Torque relaxation when the bolt is first tightened
There are many potential failure modes for bolted joint.
Torque relaxation when the bolt is first tightened.
Why does this occur. ? • Compressive force in bolted joint are very large. • M14 Grade 10.9 116kN (11.6 Tonnes) • 3.5 x Fully Laden Discovery T5
3
1
Flanged Nut
1 2
3
Flanged Nut
Tension
Com
pres
sion
Com
pres
sion
Tension
Compression Compression
Compression Compression
Bolt
21 JLR Proprietary
Bolting Diagram Effect of External load on a Clamp Load
Load
Lev
el
E X t L E o R a N d A L
FA
Additional Bolt Load
FSA
Reduction In Joint
Load FPA
Bolt /Joint Clamp Load
Fv
Resultant Joint
Load FKR
Bolt
Joint Resultant
Bolt Load
Clamp Load Reduction from A to B
A
B
displacement
23 JLR Proprietary
Plate 2
Plate 1
Bolted Joint - Stiffness & Area Calculations
Plate 1
Plate 2
Washer
Washer
Flange head
B o l t Nut
Bolt dw
Nut dw
24 JLR Proprietary
Systematic Flow
Size / Gauge
Topology Opt
Shape / Topography
Non-Linear Model
Targets-Displacement Stress Plastic strain Slip Capacity Fatigue
Bolt Joint Stiffness
Design Interpretation
Package Space
Contact Bolt preload
Yield Stress
Non-Linear Matl
Material Grade Bolt :- No / Size / Position
Neuber
Linear Model
Solid
Shell
Shell
Mixed
Optimised Design
Design &/or
Linearization Issues
Update Linear Model
Load Paths
Initial Concept Design
Critical characteristics Loads
Strain-Life
d
esig
n fre
edom
redu
ced
Not everything can be linearized
Non-Linear Model
Linearization Check
Yes No
No
25 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
26 JLR Proprietary
Optimised Trailer Towing
For TPJLR.00.008
Optimised 22% Mass Reduction
Baseline
Improved EDT system has added a similar
weight saving
27 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS
• Systematic FLOW overview
• Problem Understanding P-diagram • Bolted Joints • Non-Linear Material in Linear Analysis
• Critical Characteristic – Topology
• Application of Systematic Approach
• Lessons Learnt
28 JLR Proprietary
Lessons Learnt
Improved CAE methods, Material model, Loads & Targets Increases the capability & confidence in CAE to predict:-
• Ever more challenging engineering problems with high degree of accuracy. • Explore design opportunities & Identify design issues • Identification critical characteristics
Need to Improve Dissemination of Important critical characteristics • Provide key fact holders information in manageable form
• ‘Ball Joint offset vs. Mass’ Spreadsheet
• Greater understanding Leads to more efficient designs • Empowers Key fact holders
• Improved Data Driven Design processes • Utilised earlier – where greater design freedom & opportunities exist.
• Greater Customer satisfaction
29 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
• PALS • Parameter Diagram
• Non-Linear Material in Linear Analysis
• Systematic Approach • Critical Characteristic – Topology
• Bolted Joints
• Application of Systematic Approach
• Lessons Learnt
30 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
Thank you very much for Listening
Do you have any Questions ?
Acknowledgements:
Load - Prashant Khapane – JLR
Load - Jagan Senapathy - JLR
Optimisation - Greg Nunn - Altair Engineering
Bolted - Tim Willment – Altair Engineering
31 JLR Proprietary
Land Rover Discovery 3.0 SDV6 XS Category: 1900 kg+ “Still the best all-round heavy weight tow car” The Land Rover Discovery has now won the heaviest weight class seven times in eight years, making it the most successful model in the history of the Tow car awards.
Jaguar XF Sportbrake 3.0 V6 Diesel S Portfolio Category: 1700 – 1899 kg “Superb to tow with and brilliant to drive every day” Winner of it’s class for the second year
Range Rover Sport 3.0 SDV6 Autobiography Dynamic Category: 1900 kg+ Money No Object Tow Car “Superb to tow with and brilliant to drive every day” “If you have the means, this is the ultimate tow car”
32 JLR Proprietary
Land Rover Discovery HSE Luxury 3.0 SDV6 Judges Comments: “Effortless smooth gear changes, very comfortable” “Always in the right gear and no hunting” “Brilliant electric handbrake so held well and released when pulled away”
2015 Awards
Jaguar XF Sportbrake 3.0D V6 Portfolio Judges Comments: “Pulled like a train, lovely engine” “Effortless” “Efficient, tactile, comfortable”
Category: Over £40K 2015 TOWCAR of the Year
33 JLR Proprietary
A Systematic Approach to Weight Saving of Trailer Towing Systems at Land Rover
Thank you very much for Listening
Do you have any Questions ?
Acknowledgements:
Load - Prashant Khapane – JLR
Load - Jagan Senapathy - JLR
Optimisation - Greg Nunn - Altair Engineering
Bolted - Tim Willment – Altair Engineering