1. Race Car Steering Redesign Group 6: Joseph Haydu Joseph Haydu Brian Quinn Brian Quinn Noelle Bomberger Noelle Bomberger Assisted by Assisted by Jim Waterman Jim WatermanAdvisor: Jan Nazalewicz, P. E. Jan Nazalewicz, P. E.

2. Overview Objectives Objectives Optimized design Optimized design Give future group head start in competition Give future group head start in competition Deliverables Deliverables Reports and Presentations for ME 424 Reports and Presentations for ME 424 Final design and Analysis Final design and Analysis Fabricated steering system Fabricated steering system

3. Previous System

4. Analysis of Previous System Geometry did not comply to Ackermann Equations Geometry did not comply to Ackermann Equations System became mis-aligned regularly System became mis-aligned regularly Investigated quick release mechanism Investigated quick release mechanism

5. Ackermann Equations R = (B/2) + [L / tan(α in )] R = (B/2) + [L / tan(α in )] α out = ArcTan{ 1/ [(B/L)+(1/Tan(α in ))] } α out = ArcTan{ 1/ [(B/L)+(1/Tan(α in ))] } R - Radius of Turn B - Distance between front and rear axle L - Distance to convergent point of steering linkages α in - Angle of inside wheel turn α out - Angle of outside wheel turn

6. Ackermann Geometry

7. Steering System Steering Wheel Steering Wheel Quick Release Quick Release Steering Column Steering Column Rack and pinion Gearing Rack and pinion Gearing Steering Linkages Steering Linkages

8. Turning Performance Inputs Inputs Total car weight (W) = 815 lbf Total car weight (W) = 815 lbf Height of car Center of Gravity from road (h) = 1.5 ft Height of car Center of Gravity from road (h) = 1.5 ft Distance between wheels on axles (wb) = 3.92 ft Distance between wheels on axles (wb) = 3.92 ft Coefficient of friction for wheels is 1 Coefficient of friction for wheels is 1 Information from Ackerman Equations Information from Ackerman Equations Assumed weight distribution even between front and rear axles Assumed weight distribution even between front and rear axles Outputs Conditions Outputs Conditions Car tipping Car tipping Sliding sideways Sliding sideways

9. New Design Analysis Ackermann Analysis Old Design Analysis

10. Linkage Specifications Rack and pinion in front of axle Rack and pinion in front of axle Ackermann Steering Ackermann Steering Minimize fabrication for maximum benefit Minimize fabrication for maximum benefit Analyzed model through SolidWorks to minimize error from Ackermann Equations Analyzed model through SolidWorks to minimize error from Ackermann Equations Final Decision: Construct and test new linkages Final Decision: Construct and test new linkages

11. Linkage Redesign

13. Model of New Steering System

14. Quick Release Goals Minimize time for driver to exit vehicle Minimize time for driver to exit vehicle Difficult to false trigger Difficult to false trigger Ease of use Ease of use Ergonomics Ergonomics Final decision: not sufficient improvement over existing design to warrant construction Final decision: not sufficient improvement over existing design to warrant construction

15. Quick Release Designs

16. Still to come Final Report Final Report Testing Testing Cushion stoppages to prevent damage and mis- alignment due to mechanical shock Cushion stoppages to prevent damage and mis- alignment due to mechanical shock