Contents
Preface ...... xi Preface to Second Edition ...... xiii Symbols...... xv
CHAPTER 1 Vehicle Dynamics and Control ...... 1 1.1 Definition of the Vehicle...... 1 1.2 Virtual Four-Wheel Vehicle Model ...... 1 1.3 Control of Motion...... 2
CHAPTER 2 Tire Mechanics ...... 5 2.1 Preface...... 5 2.2 Tires Producing Lateral Force ...... 5 2.2.1 Tire and Side-Slip Angle...... 5 2.2.2 Deformation of Tire with Side Slip and Lateral Force ...... 7 2.2.3 Tire Camber and Lateral Force...... 8 2.3 Tire Cornering Characteristics...... 9 2.3.1 Fiala’s Theory...... 9 2.3.2 Lateral Force...... 19 2.3.3 Self-Aligning Torque...... 25 2.3.4 Camber Thrust...... 26 2.4 Traction, Braking, and Cornering Characteristics...... 28 2.4.1 Mathematical Model ...... 28 2.4.2 Tire Lateral Force During Traction and Braking ...... 30 2.4.3 Self-Aligning Torque...... 35 2.5 Dynamic Characteristics...... 40 2.5.1 Lateral Force Dynamic Characteristics...... 40 2.5.2 Self-Aligning Torque Dynamic Characteristics...... 42 Problems ...... 43 References...... 44
CHAPTER 3 Fundamentals of Vehicle Dynamics ...... 45 3.1 Preface...... 45 3.2 Vehicle Equations of Motion...... 45 3.2.1 Equations of Motion with Fixed Coordinates on the Vehicle ...... 45 3.2.2 Equations of Motion with Fixed Coordinates on the Ground ...... 52
v vi CONTENTS
3.3 Vehicle Steady-State Cornering...... 56 3.3.1 Description of Steady-State Cornering ...... 56 3.3.2 Steady-State Cornering and Steer Characteristics ...... 61 3.3.3 Steady-State Cornering and Tire Nonlinear Characteristics ...... 73 3.4 Vehicle Dynamic Characteristics...... 79 3.4.1 Vehicle Transient Response to Steering Input...... 79 3.4.2 Steering Response Transfer Function and Response Time History...... 88 3.4.3 Vehicle Response to Periodic Steering Input...... 96 3.4.4 Effect of Nonlinear Tire Characteristics...... 103 Problems ...... 107 References...... 107
CHAPTER 4 Vehicle Motion by Disturbances ...... 109 4.1 Preface...... 109 4.2 Motion by Lateral Force Exerted on the Center of Gravity ...... 109 4.2.1 Vehicle Motion to a Step Change in Lateral Force...... 109 4.2.2 Vehicle Motion to Impulse Lateral Force...... 121 4.2.3 Vehicle Motion due to External Disturbances and Steer Characteristics ...... 123 4.3 Vehicle Motion due to a Lateral Wind Disturbance ...... 127 4.3.1 Lateral Wind Disturbance Force...... 127 4.3.2 Vehicle Motion to Lateral Wind with Constant Speed...... 128 4.3.3 Vehicle Motion due to a Lateral Wind Gust...... 131 4.4 Conclusion of Vehicle Motion by Disturbances ...... 136 Problems ...... 136 References...... 137
CHAPTER 5 Steering System and Vehicle Dynamics ...... 139 5.1 Preface...... 139 5.2 Steering System Model and Equations of Motion...... 139 5.3 Effects of Steering System Characteristics on Vehicle Motion.....142 5.3.1 Effects of Steering System Characteristics on Vehicle Motion with Fixed Steering Angle ...... 142 5.3.2 Effects of Steering System Characteristics on Vehicle Motion with Non-Fixed Steering Angle ...... 146 5.3.3 Effects of Driver’s Hands and Arms...... 149 Problems ...... 151 References...... 152 CONTENTS vii
CHAPTER 6 Vehicle Body Roll and Vehicle Dynamics...... 153 6.1 Preface...... 153 6.2 Roll Geometry...... 153 6.2.1 Roll Center and Roll Axis...... 153 6.2.2 Roll Stiffness and Load Transfer ...... 156 6.2.3 Camber Change and Roll Steer...... 158 6.3 Body Roll and Vehicle Steer Characteristics ...... 161 6.3.1 Load Transfer Effect ...... 161 6.3.2 Camber Change Effect ...... 163 6.3.3 Roll Steer Effect...... 164 6.3.4 Suspension Lateral Stiffness and Its Effect ...... 166 6.4 Equations of Motion Inclusive of Roll...... 167 6.4.1 Coordinate System and Dynamic Model...... 168 6.4.2 Inertias ...... 169 6.4.3 External Force ...... 174 6.4.4 Equations of Motion...... 176 6.5 Effect of Steady-State Body Roll on Vehicle Dynamics ...... 178 6.6 Effects of Body Roll on Vehicle Stability...... 182 Problems ...... 185 References...... 186
CHAPTER 7 Vehicle Motion with Traction and Braking ...... 187 7.1 Preface...... 187 7.2 Equations of Motion Inclusive of Longitudinal Motion...... 187 7.3 Vehicle Quasi-Steady-State Cornering ...... 188 7.3.1 Expansion of the Stability Factor for Traction/Braking...... 188 7.3.2 Effect of Traction and Braking on Cornering...... 194 7.4 Vehicle Transient Steering Response ...... 195 7.4.1 Equations of Motion...... 195 7.4.2 Transient Response to Steering Input ...... 197 References...... 200
CHAPTER 8 Vehicle Active Motion Controls...... 201 8.1 Preface...... 201 8.2 Vehicle Motion with Additional Rear-Wheel Steering...... 201 8.2.1 Rear-Wheel Steering Proportional to Front-Wheel Steering...... 202 8.2.2 Rear-Wheel Steering Proportional to Front-Wheel Steering Force...... 204 8.2.3 Rear-Wheel Steering Proportional to Yaw Rate...... 206 viii CONTENTS
8.3 Rear-Wheel Steering Control for Zero Side-Slip Angle...... 208 8.3.1 Rear-Wheel Steering in Response to Front-Wheel Steering Angle...... 208 8.3.2 Rear-Wheel Steering Proportional to Front-Wheel Steering and Yaw Rate...... 209 8.4 Model Following Control by Rear-Wheel Steering...... 210 8.4.1 Feed-Forward Yaw Rate Model Following Control ...... 210 8.4.2 Feed-Forward and Yaw Rate Feed-Back Model Following Control ...... 211 8.4.3 Feed-Forward Lateral Acceleration Model Following Control...... 212 8.5 Model Following Front-Wheel Active Steering Control ...... 213 8.5.1 Feed-Forward Yaw Rate Model Following Control ...... 213 8.5.2 Feed-Forward and Yaw Rate Feed-Back Model Following Control ...... 213 8.5.3 Feed-Forward Lateral Acceleration Model Following Control...... 214 8.6 Front- and Rear-Wheel Active Steering Control ...... 214 8.7 Direct Yaw-Moment Control...... 218 8.7.1 Passive-Type Yaw-Moment Control ...... 218 8.7.2 DYC for Zero Side-Slip Angle ...... 222 8.7.3 Model Following DYC...... 225 8.7.4 Advantage of DYC ...... 228 References...... 229
CHAPTER 9 Vehicle Motion with All-Wheel Control ...... 231 9.1 Preface...... 231 9.2 Tire Force Distribution ...... 231 9.2.1 Constraints to Have an Intended Vehicle Response ...... 232 9.2.2 Distribution Norm ...... 233 9.2.3 Distribution Control ...... 235 9.3 Effects of Distribution Control...... 237 9.3.1 Effect of Distribution Control Minimizing Tire Workload...... 237 9.3.2 Effect of Distribution Control Minimizing Tire Slip Energy Dissipation ...... 239 9.4 Roll Control Integrated with Tire Force Distribution Control...... 243 9.4.1 Additional Constraint to Control Vehicle Body Roll ...... 243 9.4.2 Distribution Control ...... 244 9.4.3 Effects of Roll Control...... 245 9.5 Further Development of All-Wheel Control ...... 247 References...... 248 CONTENTS ix
CHAPTER 10 Vehicle Motion with Human Driver ...... 249 10.1 Preface ...... 249 10.2 Human Control Action ...... 249 10.3 Vehicle Motion Under Driver Control ...... 251 10.3.1 Driver Model ...... 251 10.3.2 Vehicle Motion Following a Course ...... 252 10.3.3 Motion Stability...... 254 10.4 Human Adaptation to Vehicle Characteristics and Lane Change Behavior ...... 260 Problems ...... 266 References...... 266
CHAPTER 11 Vehicle Handling Quality...... 267 11.1 Preface ...... 267 11.2 Vehicle Controllability...... 267 11.3 Vehicle Motion Characteristics and Controllability...... 268 11.3.1 Steer Characteristics and Controllability ...... 268 11.3.2 Dynamic Characteristics and Controllability...... 270 References...... 279
CHAPTER 12 Driver Model-Based Handling Quality Evaluation ..... 281 12.1 Preface ...... 281 12.2 Driver Model and Parameter Identification ...... 281 12.2.1 Driver Model ...... 282 12.2.2 Parameter Identification ...... 282 12.3 Driver Parameters Reflecting Driver Characteristics...... 283 12.4 Driver Parameters Reflecting Vehicle Handling Characteristics...... 284 12.4.1 Driver Parameters to Vehicle Speed ...... 285 12.4.2 Driver Parameters to Tire Characteristics...... 287 12.5 Handling Quality Evaluation Based on Driver Parameter...... 291 12.5.1 Handling Quality to Natural Frequency and Damping Ratio...... 291 12.5.2 Handling Quality to Steering Torque...... 292 12.5.3 Handling Quality to Disturbance Sensitivity...... 297 12.5.4 Effect of Stabilizing Vehicle Motion ...... 300 References...... 301
Index ...... 303