Leland Decker James Truskin

Size: px

Start display at page:

Download "Leland Decker James Truskin"

Alaina Boyd
5 years ago
Views:

1 Leland Decker James Truskin Chrysler Group LLC 2013 Chrysler Group LLC

Overview 1. Introduction to the Aluminum X-Brace 2. 2013 SRT Viper Lightweight Body Technologies 3.

2 Overview 1. Introduction to the Aluminum X-Brace SRT Viper Lightweight Body Technologies 3. Concept Design and Development Process 4. Carbon Fiber X-Brace Attachment to the Body Frame 5. Conclusion 6. Questions

3 The Aluminum X-Brace Multi-Piece Aluminum Assembly (4) Feet Castings (1) Center Web Casting (4) Extrusion Pieces (Legs) Mass = 2.7 kg Torsional Stiffness Increase: ~40% 3

4 Viper Lightweight Body Technologies Carbon Fiber Carbon Fiber Hood, Roof and Lift Gate Aluminum RRIM Thermoplastic Aluminum Doors (with Superform Door Outers) Magnesium Dash Panel Casting RRIM Fascias and Rear Quarter Panels Aluminum Side Sills 4

5 Concept & Design Development 5

6 X-Brace Design Process Overview Topology Optimization Section Optimization Design Optimization Optimize the use of material for the specified load conditions BIW torsion loadcase Optimize the section profile Type of Section Size of Section Refine the structural topology Optimize the material layup, distribution & thickness Match baseline (Aluminum X-Brace) BIW torsion stiffness 6

7 Topology Optimization Process Topology Optimization was used to develop highly efficient structural concepts with the minimum use of material to meet the performance targets DESIGN VOLUME Attached to full BIW CAE model 7

$Volfrac 10% Objective: Min.$ $Volfrac Constraint: Displacement$ Objective: Min. [2] 8

8 Topology Optimization Example Outputs DESIGN VOLUME Objective: Min. Compliance Constraint: Volfrac 10% Objective: Min. Volfrac Constraint: Displacement [1] Objective: Min. Compliance Constraint: Volfrac 5% Objective: Min. Volfrac Constraint: Displacement [2] 8

9 Concept Genealogy Initial Concept Development Topology Optimization Concept Synthesis Concept Refinement Styling Input Section Optimization Geometry Sensitivity Studies Structural Efficiency Increases Design Optimization Refined Styling Input Material & Thickness Optimization 9

Section Development 3 Section profiles were initially considered - 1-Piece Open C-Channel - 2-Piece Closed C-Channel (w/ adhesive joint) - 2-Piece Closed Section

variables were adjusted ±50% from baseline - 380 Open C-Channel & >100 Closed-Section profiles were evaluated for I xx and I yy values - Optimum candidates were

10 Section Development 3 Section profiles were initially considered - 1-Piece Open C-Channel - 2-Piece Closed C-Channel (w/ adhesive joint) - 2-Piece Closed Section with foam core Section optimization of the open channel indicated bending stiffness targets of the legs could be reached with an Open C-Channel - Width & Height variables were adjusted ±50% from baseline Open C-Channel & >100 Closed-Section profiles were evaluated for I xx and I yy values - Optimum candidates were determined by identifying a section whose I values were equal to or better than the baseline values, but with a lower cross-section area to save weight +19% Stiffness Increase 10

control factors The study indicated that the Rear Leg, Material Overlaps and Front Leg design variables were most sensitive to stiffness

11 Geometry Sensitivity Studies The ANOVA (ANalysis Of VAriance) process, a valuable tool in Design for Six-Sigma (DFSS), was applied to the geometry to identify the most sensitive variables to stiffness and mass - L18 Matrix with (1) 2-Level control factor & (7) 3-level control factors The study indicated that the Rear Leg, Material Overlaps and Front Leg design variables were most sensitive to stiffness & mass - This lead to the improvement of the rear leg Hockey Stick topology to counteract the lateral bending load about the rear attachment 11

12 Design History 12

13 X-Brace Attachment to the Body Frame 13

14 Attaching to the Body Frame Click Bond bushings from the aerospace industry provide corrosion isolation & prevent compression loads from being applied directly to the carbon fiber Adhesive Bushings are a two-piece assembly of passivated stainless steel and adhesively bonded into place Carry-over frame attachment locations 14

Attaching to the Body Frame With the Click Bond

replacement for the production aluminum part The same

fiber X-Brace, and safely tightened to the same torque

15 Attaching to the Body Frame With the Click Bond solution, the carbon fiber X- Brace is a simple replacement for the production aluminum part The same (8) M8 threaded fasteners can be used on the new carbon fiber X-Brace, and safely tightened to the same torque specification Aluminum X-Brace Installed Carbon-Fiber X-Brace Installed 15

matches the BIW torsion stiffness of the aluminum X-Brace 36-week design, development,

16 Results and Conclusions A Carbon Fiber Design Process lead by virtual tools and topology optimization 50% mass savings over the aluminum X-Brace The CFRP X-Brace matches the BIW torsion stiffness of the aluminum X-Brace 36-week design, development, manufacturing and validation cycle time MOPAR-ready accessory for SRT Viper aftermarket customers 16

17 Thank you for your attention! 17

Value Through Solutions

Value Through Solutions 1 2 The information contained within this presentation is intended solely as a guide for the customers of Semblex Corporation. This information may not be copied or distributed beyond the initial audience