Fundamentals of Vehicle Dynamics

by Gillespie, Thomas D.

• ISBN13: 9781560911999
• ISBN10: 1560911999
• Format: Hardcover
• Copyright: 1992-03-01
• Publisher: Society of Automotive Engineers

Table of Contents

Introduction	1	(20)
Dawn of the Motor Vehicle Age	1	(4)
Introduction to Vehicle Dynamics	5	(2)
Fundamental Approach to Modeling	7	(4)
Lumped Mass	7	(1)
Vehicle Fixed Coordinate System	8	(1)
Motion Variables	8	(1)
Earth Fixed Coordinate System	9	(1)
Euler Angles	10	(1)
Forces	10	(1)
Newton's Second Law	10	(1)
Dynamic Axle Loads	11	(3)
Static Loads on Level Ground	13	(1)
Low-Speed Acceleration	13	(1)
Loads on Grades	13	(1)
Example Problems	14	(5)
References	19	(2)
Acceleration Performance	21	(24)
Power-Limited Acceleration	21	(11)
Engines	21	(2)
Power Train	23	(5)
Automatic Transmissions	28	(4)
Example Problems	32	(3)
Traction-Limited Acceleration	35	(5)
Transverse Weight Shift due to Drive Torque	35	(4)
Traction Limits	39	(1)
Example Problems	40	(2)
References	42	(3)
Braking Performance	45	(34)
Basic Equations	45	(3)
Constant Deceleration	46	(1)
Deceleration with Wind Resistance	47	(1)
Energy/Power	48	(1)
Braking Forces	48	(2)
Rolling Resistance	48	(1)
Aerodynamic Drag	49	(1)
Driveline Drag	49	(1)
Grade	50	(1)
Brakes	50	(4)
Brake Factor	51	(3)
Tire-Road Friction	54	(3)
Velocity	56	(1)
Inflation Pressure	57	(1)
Vertical Load	57	(1)
Example Problems	57	(2)
Federal Requirements for Braking Performance	59	(1)
Brake Proportioning	60	(7)
Anti-Lock Brake Systems	67	(2)
Braking Efficiency	69	(2)
Rear Wheel Lockup	71	(3)
Pedal Force Gain	74	(1)
Example Problem	75	(1)
References	76	(3)
Road Loads	79	(46)
Aerodynamics	79	(31)
Mechanics of Air Flow Around a Vehicle	79	(5)
Pressure Distribution on a Vehicle	84	(3)
Aerodynamic Forces	87	(1)
Drag Components	88	(5)
Aerodynamics Aids	93	(1)
Bumper Spoilers	93	(1)
Air Dams	94	(1)
Deck Lid Spoilers	94	(1)
Window and Pillar Treatments	95	(1)
Optimization	95	(2)
Drag	97	(1)
Air Density	97	(1)
Drag Coefficient	98	(3)
Side Force	101	(2)
Lift Force	103	(1)
Pitching Moment	103	(1)
Yawing Moment	104	(1)
Rolling Moment	105	(1)
Crosswind Sensitivity	106	(4)
Rolling Resistance	110	(8)
Factors Affecting Rolling Resistance	111	(1)
Tire Temperature	111	(1)
Tire Inflation Pressure/Load	112	(1)
Velocity	113	(1)
Tire Material and Design	114	(2)
Tire Slip	116	(1)
Typical Coefficients	116	(2)
Total Road Loads	118	(3)
Fuel Economy Effects	120	(1)
Example Problems	121	(2)
References	123	(2)
Ride	125	(70)
Excitation Sources	126	(20)
Road Roughness	126	(6)
Tire/Wheel Assembly	132	(6)
Driveline Excitation	138	(5)
Engine/Transmission	143	(3)
Vehicle Response Properties	146	(35)
Suspension Isolation	147	(7)
Example Problem	154	(1)
Suspension Stiffness	154	(2)
Suspension Damping	156	(3)
Active Control	159	(5)
Wheel Hop Resonances	164	(2)
Suspension Nonlinearities	166	(2)
Rigid Body Bounce/Pitch Motions	168	(4)
Bounce/Pitch Frequencies	172	(6)
Special Cases	178	(1)
Example Problem	178	(3)
Perception of Ride	181	(8)
Tolerance to Seat Vibrations	181	(6)
Other Vibration Forms	187	(2)
Conclusion	189	(1)
References	189	(6)
Steady-State Cornering	195	(42)
Introduction	195	(1)
Low-Speed Turning	196	(2)
High-Speed Cornering	198	(11)
Tire Cornering Forces	198	(1)
Cornering Equations	199	(3)
Understeer Gradient	202	(2)
Characteristic Speed	204	(1)
Critical Speed	204	(1)
Lateral Acceleration Gain	205	(1)
Yaw Velocity Gain	205	(1)
Sideslip Angle	206	(2)
Static Margin	208	(1)
Suspension Effects on Cornering	209	(17)
Roll Moment Distribution	210	(7)
Camber Change	217	(3)
Roll Steer	220	(1)
Lateral Force Compliance Steer	221	(2)
Aligning Torque	223	(1)
Effect of Tractive Forces on Cornering	223	(3)
Summary of Understeer Effects	226	(1)
Experimental Measurement of Understeer Gradient	227	(4)
Constant Radius Method	227	(2)
Constant Speed Method	229	(2)
Example Problems	231	(4)
References	235	(2)
Suspensions	237	(38)
Solid Axles	238	(3)
Hotchkiss	238	(1)
Four Link	239	(1)
De Dion	240	(1)
Independent Suspensions	241	(7)
Trailing Arm Suspension	241	(1)
SLA Front Suspension	242	(1)
MacPherson Strut	243	(1)
Multi-Link Rear Suspension	244	(1)
Trailing-Arm Rear Suspension	245	(1)
Semi-Trailing Arm	245	(2)
Swing Axle	247	(1)
Anti-Squat and Anti-Pitch Suspension Geometry	248	(6)
Equivalent Trailing Arm Analysis	248	(2)
Rear Solid Drive Axle	250	(2)
Independent Rear Drive	252	(1)
Front Solid Drive Axle	253	(1)
Independent Front-Drive Axle	253	(1)
Four-Wheel Drive	254	(1)
Anti-Dive Suspension Geometry	254	(2)
Example Problems	256	(1)
Roll Center Analysis	257	(12)
Solid Axle Roll Centers	259	(1)
Four-Link Rear Suspension	259	(1)
Three-Link Rear Suspension	260	(1)
Four-Link with Parallel Arms	261	(1)
Hotchkiss Suspension	262	(1)
Independent Suspension Roll Centers	263	(1)
Positive Swing Arm Geometry	264	(1)
Negative Swing Arm Geometry	265	(1)
Parallel Horizontal Links	266	(1)
Inclined Parallel Links	267	(1)
MacPherson Strut	267	(1)
Swing Axle	268	(1)
Active Suspensions	269	(5)
Suspension Categories	269	(1)
Functions	270	(1)
Performance	271	(3)
References	274	(1)
The Steering System	275	(34)
Introduction	275	(1)
The Steering Linkages	275	(4)
Steering Geometry Error	279	(3)
Toe Change	280	(1)
Roll Steer	281	(1)
Front Wheel Geometry	282	(2)
Steering System Forces and Moments	284	(7)
Vertical Force	286	(3)
Lateral Force	289	(1)
Tractive Force	290	(1)
Aligning Torque	291	(1)
Rolling Resistance and Overturning Moments	291	(1)
Steering System Models	291	(2)
Examples of Steering System Effects	293	(4)
Steering Ratio	293	(1)
Understeer	294	(1)
Braking Stability	295	(2)
Influence of Front-Wheel Drive	297	(4)
Driveline Torque About the Steer Axis	297	(2)
Influence of Tractive Force on Tire Cornering Stiffness	299	(1)
Influence of Tractive Force on Aligning Moment	300	(1)
Fore/Aft Load Transfer	300	(1)
Summary of FWD Understeer Influences	300	(1)
Four-Wheel Steer	301	(4)
Low-Speed Turning	301	(2)
High-Speed Cornering	303	(2)
References	305	(4)
Rollover	309	(26)
Quasi-Static Rollover of a Rigid Vehicle	310	(4)
Quasi-Static Rollover of a Suspended Vehicle	314	(3)
Transient Rollover	317	(10)
Simple Roll Models	318	(4)
Yaw-Roll Models	322	(2)
Tripping	324	(3)
Accident Experience	327	(4)
References	331	(4)
Tires	335	(42)
Tire Construction	336	(1)
Size and Load Rating	337	(1)
Terminology and Axis System	338	(2)
Mechanics of Force Generation	340	(2)
Tractive Properties	342	(5)
Vertical Load	344	(1)
Inflation Pressure	345	(1)
Surface Friction	345	(1)
Speed	346	(1)
Relevance to Vehicle Performance	346	(1)
Cornering Properties	347	(8)
Slip Angle	348	(4)
Tire Type	352	(1)
Load	353	(1)
Inflation Pressure	354	(1)
Size and Width	354	(1)
Tread Design	354	(1)
Other Factors	355	(1)
Relevance to Vehicle Performance	355	(1)
Camber Thrust	355	(4)
Tire Type	356	(2)
Load	358	(1)
Inflation Pressure	358	(1)
Tread Design	359	(1)
Other Factors	359	(1)
Relevance to Vehicle Performance	359	(1)
Aligning Moment	359	(4)
Slip Angle	360	(1)
Path Curvature	361	(1)
Relevance to Vehicle Performance	362	(1)
Combined Braking and Cornering	363	(4)
Friction Circle	364	(2)
Variables	366	(1)
Relevance to Vehicle Performance	366	(1)
Conicity and Ply Steer	367	(2)
Relevance to Vehicle Performance	369	(1)
Durability Forces	369	(2)
Tire Vibrations	371	(4)
References	375	(2)
Appendix A - SAE J670e - Vehicle Dynamics Terminology	377	(36)
Appendix B - SAE J6a - Ride and Vibration Data Manual	413	(58)
Index	471