Project Squeaky WheelTeam Autobots

Customer Continental AutomotiveDavid Agnew, Jeremy McClain

Fall 2011

Project Overview

• Steer-by-wire replaces the traditional steering system with an electronic one

• Motivation‒ To remove the mechanical system from the vehicle,

reducing power consumption‒ To provide more responsive steering‒ Car Design improvements‒ A possible future with complete autonomy

Domain Research

• Steer-by-wire is a very new technology• Most material available is from research

projects• Not used in personal transportation vehicles

yet• Primary use currently is in industrial

equipment (forklifts, some agricultural vehicles)

Overview of Features

• Basic look at steer by wire control• Simple control loop using PID to ensure proper

control

Requested Angle

Current Wheel Angle

PID Torque Request

New Wheel Angle

Project Constraints

• The system is only active in the speed range of -10 to 20 miles per hour

• System must recalculate values every 500µs• The assisted torque is always within the range

of +10 to -10 Nm.

Model-based View of System

• Contains the following diagrams

• Use Case• Class • Sequence• State

Use Case Diagram

Class Diagram

Sequence Diagram

State Diagram

Prototype Overview

Demonstration – Scenario 1

• Speed: -5 mph• Steering Wheel Adjustment : Left

Demonstration – Scenario 2

• Speed: 0 mph• Steering Wheel Adjustment : Left

Demonstration – Scenario 3

• Speed: 20 mph• Steering Wheel Adjustment : Right

Questions?