1. E- 579 Mechatronics Modeling and Simulation Term Project - “ Steer By Wire” Instructor Dr. Shuvra Das
Divesh Mittal

2. E-579 - Steer By Wire system
Contents
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
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3. Introduction and Significance
By wire system is getting popular because of its efficient and accurate operations.
There are still few concerns and issues.
Idea here is to model simple steer by wire system and see if we can replicate the results from existing hydraulic steering system.
This is simple model to understand, idea needs to be extended in order to get more close to real world.
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4. E-579 - Steer By Wire system
Problem Definition
Understand and prepare system level model of Steer By Wire (SBW) system.
Making the suitable assumptions to break down whole system into simple energy storage or dissipating elements.
Convert above information into bond graph model and simulate it on 20-SimTM.
Plot wheel angle and validate it with similar results from other references.
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5. E-579 - Steer By Wire system
[“Embedded Steer-by-Wire System Development”, Embedded World, February 2004, Nuremberg, Germany]
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6. Reference: http://www.Howstuffworks.com
Steer by Wire
Reference:
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7. E-579 - Steer By Wire system
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
April 17, 2006
E Steer By Wire system

8. E-579 - Steer By Wire system
System Level Model
SBW
Steering Wheel Subsystem
Controller Subsystem
Front Wheel Subsystem
Steering Wheel Motor
Steering Actuator (Motor)
Control Unit
Reactive torque
Control Path
Torque Sensor
Rack / Pinion Gear
Steering Angle Sensor
Tie rod
Steering Column
Tire-Wheel subsystem
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9. E-579 - Steer By Wire system
Modeling of SBW
SBW system is composed of steering subsystem, controller and tire subsystem.
Model subsystems with the help of major components.
Each component is a combination of capacitive/inertia/resistor elements and is connected to other components with either a transformer / gyrator elements or series / parallel junction.
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10. E-579 - Steer By Wire system
Block Diagram
Torque Input
Control Unit
DC Motor
Rack /pinion gear
Tire/wheel assembly
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11. E-579 - Steer By Wire system
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
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12. Manual Rack and pinion steering system
Steering wheel/ column
Rack and pinion / tire assembly
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13. Without feedback/No control
Front wheel actuator motor
Rack/Pinion, tie rod and tire asembly
Steering wheel
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14. E-579 - Steer By Wire system
Data[3]
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15. E-579 - Steer By Wire system
Front wheel angle
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16. E-579 - Steer By Wire system
Validation
Result from reference [1]
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17. Front wheel angle Vs steering wheel angle
1.70
400
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18. E-579 - Steer By Wire system
Steering subsystem
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19. E-579 - Steer By Wire system
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
April 17, 2006
E Steer By Wire system

20. E-579 - Steer By Wire system
SBW Controller
Steering wheel Motor Controller
Front wheel actuator motor controller
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21. E-579 - Steer By Wire system
Controller
SBW controller [3]
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22. Steering Motor Controller
Generates reactive torque.
Easy to drive at low speed and vice versa.
Reactive torque is function of velocity
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23. Gain factor for Steering control
Gain for steering motor actuator [3]
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24. Feed forward control Bicycle model for steering behavior [3]
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25. Steering Torque Controller
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26. Reaction Torque Control
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27. E-579 - Steer By Wire system
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
April 17, 2006
E Steer By Wire system

28. E-579 - Steer By Wire system
Results
Steer by wire was modeled using bond graph technology.
Controller for SBW improves maneuverability and handling.
Reactive torque can be controlled using torque control mechanism.
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29. Proposed Time line VS Achievement Mapping
Proposed date
Task
Status
March 13
Topic search
Achieved at time
March 20
Background research
March 27
Understanding the system
March 29
Proposal Presentation
April 02
Basic bond graph modeling
April 04
Decide on modeling complexity of sensors
April 09
Modeling of controller
Started at time but finished on April 15
April 11
Validation of results
April 17
Final presentation
April 21
Final report
Should be done in time.
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30. E-579 - Steer By Wire system
Introduction
System level modeling
Bond graph model
SBW control
Results and Discussion
Limitations and Future work
References
April 17, 2006
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31. Limitations and Future Work
Torque control mapping for steering motor.
Front wheel motor voltage control.
Importing Matlab file for lookup tables.
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32. E-579 - Steer By Wire system
References
Srihari Vijaykumar ,”Analysis of an electric power assisted steering system using bond graphs”, SAE paper
Srihari Vijaykumar ,” Application of bond graph technique to the design of passenger car steering system”, SAE paper
Se-Wook Oh,” The development of an advanced control method for the steer-by-wire system to improve the vehicle maneuverability and stability”, SAE paper
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33. E-579 - Steer By Wire system
Questions ??
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