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. Introduction (continued)
Driver Interface Sub-System
Microcontroller Sub-System
Rack-and-Pinion Sub-System
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
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
Gear Train
Pinion 1
Pinion 2

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 20.8 Nm at 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 = 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,
David G. Ullman, “The mechanical design process”, Third edition, McGrawHill, 2003, USA.
“Delphi Non-Contact Multi-Turn Rotary Position Sensor”, Delphi,
“Electric Power Assisted Steering”, Visteon, 2005.
Matweb, 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, April 2007.
Roy Mech,
“Sensors for Position Measurement: Single-turn/Multi-turn Steering-angle Sensor”, Hella International,