Slip (vehicle dynamics)

About: Slip (vehicle dynamics) is a research topic. Over the lifetime, 10166 publications have been published within this topic receiving 90779 citations. The topic is also known as: tire slip & vehicle slip.

Theory of Ground Vehicles

Abstract: Preface. Preface to the Third Edition. Preface to the Second Edition. Preface to the First Edition. Conversion Factors. Nomenclature. Introduction. 1. MECHANICS OF PNEUMATIC TIRES. 1.1 Tire Forces and Moments. 1.2 Rolling Resistance of Tires. 1.3 Tractive (Braking) Effort and Longitudinal Slip (Skid). 1.4 Cornering Properties of Tires. 1.4.1 Slip Angle and Cornering Force. 1.4.2 Slip Angle and Aligning Torque. 1.4.3 Camber and Camber Thrust. 1.4.4 Characterization of Cornering Behavior of. Tires. 1.5 Performance of Tires on Wet Surfaces. 1.6 Ride Properties of Tires. References. Problems. 2. MECHANICS OF VEHICLE-TERRAIN INTERACTION--TERRAMECHANICS. 2.1 Distribution of Stresses in the Terrain Under Vehicular Loads. 2.2 Applications of the Theory of Plastic Equilibrium to the Mechanics of Vehicle--Terrain Interaction. 2.3 Empirical Methods for Predicting Off-Road Vehicle Performance. 2.3.1 Empirical Methods Based on the Cone Index. 2.3.2 Empirical Methods Based on the Mean Maximum Pressure. 2.4 Measurement and Characterization of Terrain Response. 2.4.1 Characterization of Pressure-Sinkage Relationship. 2.4.2 Characterization of the Response to Repetitive Loading. 2.4.3 Characterization of the Shear Stress-Shear Displacement Relationship. 2.5 A Simplified Method for Analysis of Tracked Vehicle Performance. 2.5.1 Motion Resistance of a Track. 2.5.2 Tractive Effort and Slip of a Track. 2.6 A Computer-Aided Method for Evaluating the Performance of Vehicles with Flexible Tracks. 2.6.1 Approach to the Prediction of Normal Pressure Distribution under a Track. 2.6.2 Approach to the Prediction of Shear Stress Distribution under a Track. 2.6.3 Prediction of Motion Resistance and Drawbar Pull as Functions of Track Slip. 2.6.4 Experimental Substantiation. 2.6.5 Applications to Parametric Analysis and Design Optimization. 2.7 A Computer-Aided Method for Evaluating the Performance of Vehicles with Long-Pitch Link Tracks. 2.7.1 Basic Approach. 2.7.2 Experimental Substantiation. 2.7.3 Applications to Parametric Analysis and Design Optimization. 2.8 Methods for Parametric Analysis of Wheeled Vehicle Performance. 2.8.1 Motion Resistance of a Rigid Wheel. 2.8.2 Motion Resistance of a Pneumatic Tire. 2.8.3 Tractive Effort and Slip of a Wheel. 2.9 A Computer-Aided Method for Evaluating the Performance of Off-Road Wheeled Vehicles. 2.9.1 Basic Approach. 2.9.2 Experimental Substantiation. 2.9.3 Applications to Parametric Analysis. 2.10 Finite Element and Discrete Element Methods for the Study of Vehicle-Terrain Interaction. 2.10.1 The Finite Element Method. 2.10.2 The Discrete (Distinct) Element Method. References. Problems. 3. PERFORMANCE CHARACTERISTICS OF ROAD VEHICLES. 3.1 Equation of Motion and Maximum Tractive Effort. 3.2 Aerodynamic Forces and Moments. 3.3 Vehicle Power Plant and Transmission Characteristics. 3.3.1 Internal Combustion Engines. 3.3.2 Electric Drives. 3.3.3 Hybrid Drives. 3.3.4 Fuel Cells. 3.3.5 Transmission Characteristics. 3.4 Vehicle Power Plant and Transmission Characteristics. 3.4.1 Power Plant Characteristics. 3.4.2 Transmission Characteristics. 3.5 Prediction of Vehicle Performance. 3.5.1 Acceleration Time and Distance. 3.5.2 Gradability. 3.6 Operating Fuel Economy. 3.7 Engine and Transmission Matching. 3.8 Braking Performance. 3.8.1 Braking Characteristics of a Two-Axle. Vehicle. 3.8.2 Braking Efficiency and Stopping Distance. 3.8.3 Braking Characteristics of a Tractor-Semitrailer. 3.8.4 Antilock Brake Systems. 3.8.5 Traction Control Systems. References. Problems. 4. PERFORMANCE CHARACTERISTICS OF OFF-ROAD VEHICLES. 4.1 Drawbar Performance. 4.1.1 Drawbar Pull and Drawbar Power. 4.1.2 Tractive Efficiency. 4.1.3 Four Wheel Drive. 4.1.5 Coefficient of Traction. 4.1.4 Weight-to-Power Ratio for Off-Road Vehicles. 4.2 Fuel Economy of Cross-Country Operations. 4.3 Transport Productivity and Transport Efficiency. 4.4 Mobility Map and Mobility Profile. 4.5 Selection of Vehicle Configurations for Off-Road Operations. References. Problems. 5. HANDLING CHARACTERISTICS OF ROAD VEHICLES. 5.1 Steering Geometry. 5.2 Steady-State Handling Characteristics of a Two-Axle Vehicle. 5.2.1 Neutral Steer. 5.2.2 Understeer. 5.2.3 Oversteer. 5.3 Steady-State Response to Steering Input. 5.3.1 Yaw Velocity Response. 5.3.2 Lateral Acceleration Response. 5.3.3 Curvature Response. 5.4 Testing of Handling Characteristics. 5.4.1 Constant Radius Test. 5.4.2 Constant Speed Test. 5.4.3 Constant Steer Angle Test. 5.5 Transient Response Characteristics. 5.6 Directional Stability. 5.6.1 Criteria for Directional Stability. 5.6.2 Vehicle Stability Control. 5.7 Steady-State Handling Characteristics of a Tractor-Semitrailer. 5.8 Simulation Models for the Directional Behavior of Articulated Road Vehicles. References. Problems. 6. STEERING OF TRACKED VEHICLES. 6.1 Simplified Analysis of the Kinetics of Skid-Steering. 6.2 Kinematics of Skid-Steering. 6.3 Skid-Steering at High Speeds. 6.4 A General Theory for Skid-Steering on Firm Ground. 6.4.1 Shear Displacement on the Track-Ground Interface. 6.4.2 Kinetics in a Steady-State Turning Maneuver. 6.4.3 Experimental Substantiation. 6.4.4 Coefficient of Lateral Resistance. 6.5 Power Consumption of Skid-Steering. 6.6 Steering Mechanisms for Tracked Vehicles. 6.6.1 Clutch/Brake Steering System. 6.6.2 Controlled Differential Steering System. 6.6.3 Planetary Gear Steering System. 6.7 Articulated Steering. References. Problems. 7. VEHICLE RIDE CHARACTERISTICS. 7.1 Human Response to Vibration. 7.1.1 International Standard ISO 2631-1:1985. 7.1.2 International Standard ISO 2631-1:1997. 7.2 Vehicle Ride Models. 7.2.1 Two-Degree-of-Freedom Vehicle Model for Sprung and Unsprung Mass. 7.2.2 Numerical Methods for Determining the Response of a Quarter-Car Model to Irregular Surface Profile Excitation. 7.2.3 Two-Degree-of-Freedom Vehicle Model for Pitch and Bounce. 7.3 Introduction to Random Vibration. 7.3.1 Surface Elevation Profile as a Random Function. 7.3.2 Frequency Response Function. 7.3.3 Evaluation of Vehicle Vibration in Relation to the Ride Comfort Criterion. 7.4 Active and Semi-Active Suspensions. References. Problems. 8. INTRODUCTION TO AIR-CUSHION VEHICLES. 8.1 Air-Cushion Systems and Their Performance. 8.1.1 Plenum Chamber. 8.1.2 Peripheral Jet. 8.2 Resistance of Air-Cushion Vehicles. 8.3 Suspension Characteristics of Air-Cushion Systems. 8.3.1 Heave (or Bounce) Stiffness. 8.3.2 Roll Stiffness. 8.4 Directional Control of Air-Cushion Vehicles. References. Problems. Index.

Slip instability and state variable friction laws

Abstract: The dependence of the friction force on slip history is described by an experimentally motivated constitutive law where the friction force is dependent on slip rate and state variables The state variables are defined macroscopically by evolution equations for their rates of change in terms of their present values and slip rate Experiments may strongly suggest that one state variable is adequate or prove that one is inadequate Analysis of steady slip governed by a single state variable in a spring and (massless) slider predict oscillations at a critical spring stiffness k = kcrit The critical stiffness kcrit is given by a simple formula and steady slip is stable for k > kcrit and unstable for k < kcrit State variable friction laws may superficially appear as a simple slip rate dependence, slip distance dependence, or time dependent static friction, depending on experiment and testing machinery Truly complicated motion is possible in a spring-slider model if more than one state variable is used Further consequences of state variable friction laws can include creep waves and apparent rate independence for some phenomena

Tyre Modelling for Use in Vehicle Dynamics Studies

Abstract: A new way of representing tyre data obtained from measurements in pure cornering and pure braking conditions has been developed in order to further improve the Dynamic Safety of vehicles. The method makes use of a formula with coefficients which describe some of the typifying quantities of a tyre, such as slip stiffnesses at zero slip and force and torque peak values. The formula is capable of describing the characteristics of side force, brake force and self aligning torque with great accuracy. This mathematical representation is limited to steady-state conditions during either pure cornering or pure braking and forms the basis for a model describing tyre behaviour during combined braking and cornering.

The magic formula tyre model

Abstract: An account is given of the latest version 3 of the Magic Formula tyre model. The model provides a set of mathematical formulae from which the forces and moment acting from road to tyre can be calculated at longitudinal, lateral and camber slip conditions, which may occur simultaneously. The model aims at an accurate description of measured steady-state tyre behaviour. The coefficients of the basic formula represent typifying quantities of the tyre characteristic. By selecting proper values, the characteristics for either side force, aligning torque or fore and aft force can be obtained. The new version of the model contains physically based formulations to avoid the introduction of correction factors. Double-sided, possibly non-symmetric pure slip curves are employed as the basis for combined slip calculations. Suggestions are given to estimate the driving part of the longitudinal slip curve and to represent the characteristic at rolling backwards.