Design and Prototype Build of the Interfaces of a Steer-By-Wire Assembly

1. Design and Prototype Build of the Interfaces of a Steer-By-Wire Assembly Javier Angulo Alan Benedict, Team Leader Amber Russell, Team Manager Kurush Savabi Dr. Sohel Anwar, Faculty Advisor & Sponsor Dr. Hazim El-Mounayri, Course Instructor

2. Overview • Purpose & Objective • Requirements & Targets • Concept Generation & Evaluation • Product Generation & Evaluation • Conclusions & Recommendations

3. Introduction Overall Purpose: Create a steer-by-wire system parallel to that of an automobile for use in laboratory

4. Driver Interface Sub-System Microcontroller Sub-System Rack-and-Pinion Sub-System Introduction(continued) Overall Steer-By-Wire System

5. Objectives of Design Objectives: • Design of an interface between a standard automotive rack-and-pinion steering assembly and electric motors. • Design of an interface between the same rack-and-pinion steering assembly and angle position sensors • Design of a stand to support the entire system and provide reaction forces to rack

6. Requirements and Targets • Functionality and safety • Benchmark Visteon-GM Sequel

7. Requirements and Targets(continued)

8. Concept Development & Evaluation Development Process • Functional Decomposition • Function Concept-Mapping Evaluation Process • Feasibility Testing • Go/No-Go Screening • Decision Matrices • Failure Mode Effects Analysis (FMEA)

9. Final Concept • Motor to Rack-and-Pinion Interface • Gear Train • Motor to Motor Interface • Gear Train • Sensor to Sensor Interface • Stackable Sensors / Shaft • Sensor to Rack and Pinion Interface • Direct Shaft • Metal Stand Motor Controllers Position Sensors Motor Motor Stacked / Shaft Rack Pinion 1 Pinion 2 Gear Train

10. Product Generation & Evaluation Motors Requirements • Torque of 52 Nm at 67 rpm • Torque of 20.8 Nm at 133 rpm • Input voltage of <60 VDC Selected Motor Specifications • Torque of 52 Nm at 67 rpm • Torque of 20.8 Nm at 127.4 rpm • Input voltage of 75 VDC

11. Product Generation & Evaluation Motor Interfaces • Enables redundancy • Allows for maintenance

12. Product Generation & Evaluation Stand Requirements Max deflection of 12.7mm Max stress of 450MPa Stand Analysis Results Max deflection of 1.83E-4mm Max stress of 89.1MPa (Dynamic) FOS 3 to 5 (267.3MPa to 445.5MPa)

13. Product Generation & Evaluation Springs • Spring Requirements of 102 kN/m • Selected Spring Specifications of 83 kN/m • Force of 6876 N (to simulate dynamic loading) • Maximum Stress = 104.6 MPa • Yield Strength of Plate = 250 MPa

14. Product Generation & Evaluation Sensors Hollow-angle sensors • Ease of interface • Zero backlash • Lack of availability • Lower accuracy • Requires less space Conventional Potentiometers • Meet accuracy requirement • Readily available • Cost efficient • Requires gear train interface (backlash)

15. Final Design

16. Final Design (continued)

17. Engineering Requirements

18. Questions For further questions, please feel free to ask the design team or refer to the project report. Thank you.

19. References • Cesiel, Daugherty, Gaunt, “Development of a Steer-by-Wire System for the GM Sequel”, SAE Technical Paper Series, 2006-01-1173. • David G. Ullman, “The mechanical design process”, Third edition, McGrawHill, 2003, USA. • “Delphi Non-Contact Multi-Turn Rotary Position Sensor”, Delphi, www.delphi.com. • “Electric Power Assisted Steering”, Visteon, 2005. • Matweb, www.matweb.com. March 2007. • Miller, Duane K., P.E., Use “Undermatching Weld Metal Where Advantageous: Practical Ideas for the Design Professional”, Welding Innovation, Vol. XIV, No. 1, 1997. • Parker Motion, www.parkermotion.com. April 2007. • Roy Mech, www.roymech.co.uk/useful_tables/form/weld_strength • “Sensors for Position Measurement: Single-turn/Multi-turn Steering-angle Sensor”, Hella International, www.hella.com.