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The vehicle dynamics terminology presented herein pertains to passenger cars and light trucks with two axles and to those vehicles pulling single-axle trailers. The terminology presents symbols and definitions covering the following subjects: axis systems, vehicle bodies, suspension and steering systems, brakes, tires and wheels, operating states and modes, control and disturbance inputs, vehicle responses, and vehicle characterizing descriptors. The scope does not include terms relating to the human perception of vehicle response.

This SAE Recommended Practice describes a test method for measuring the forces and moments generated at a high frequency response spindle when a rolling tire impacts a cleat. The cleat is configured either with its crest perpendicular, 90 degrees, to the path of the tire or optionally with its crest inclined at an angle to the path of the tire. The carriage to which the spindle is attached is rigidly constrained in position during each test condition to provide a good approximation to fixed loaded radius operation. The method discussed in this document provides impact force and moment time histories essentially free from variations due to tire non-uniformities. The method applies to any size tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development.

This recommended practice defines methods for the measurement of periodic, random and transient whole-body vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will cause discomfort. Informative appendices indicate the current state of knowledge and provide guidance on the possible effects of motion and vibration on discomfort. The frequency range considered is 0.5 Hz to 80 Hz. This recommended practice also defines the principles of preferred methods of mounting transducers for determining human exposure. This recommended practice is applicable to light passenger vehicles (e.g., passenger cars and light trucks). This recommended practice is applicable to motions transmitted to the human body as a whole through the buttocks, back and feet of a seated occupant, as well as through the hands of a driver.

This recommended practice defines methods for the measurement of periodic, random and transient whole-body vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will cause discomfort. Informative appendices indicate the current state of knowledge and provide guidance on the possible effects of motion and vibration on discomfort. The frequency range considered is 0.5 Hz to 80 Hz. This recommended practice also defines the principles of preferred methods of mounting transducers for determining human exposure. This recommended practice is applicable to light passenger vehicles (e.g., passenger cars and light trucks). This recommended practice is applicable to motions transmitted to the human body as a whole through the buttocks, back and feet of a seated occupant, as well as through the hands of a driver.

This SAE Recommended Practice describes a test method for determining the vertical force and deflection properties of a non-rolling tire and the associated contact patch length and width. The method applies to any tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this Recommended Practice, forces applied to the pavement are not considered.

This SAE Recommended Practice describes application of two closely related test procedures, which together determine the linear range longitudinal and lateral stiffnesses of a statically loaded non-rotating tire. The procedures apply to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document, forces applied to the pavement are not considered.

This SAE Recommended Practice describes a test method for determining properties of a non-rolling tire quasi-statically enveloping either a set of triangular cleats or a single step cleat. In the case of the triangular cleats the normal force and vertical deflection of the non-rolling tire are determined. In the case of the step cleats the normal force, longitudinal force, and vertical deflection of the non-rolling tire are determined. The method applies to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire.1 The data are intended for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document, forces applied to the pavement are not considered.

This SAE Recommended Practice describes a trio of test methods which determine basic tire size (geometry), mass, and moments of inertia. The methods apply to any tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular surfaces paved or unpaved. Within the context of this Recommended Practice, forces applied to the surface on which the tire is operating are not considered.

This SAE Recommended Practice describes a test method for measuring the forces and moments generated at a spindle when a tire rolls over a rectangular obstacle, cleat, at very low speed. The cleat used in a particular test condition is configured with its crest either perpendicular, 90 degrees, to the path of the tire or optionally with its crest inclined at an angle to the path of the tire. The carriage to which the spindle is attached is rigidly constrained in position during each test condition so as to provide a good approximation to fixed loaded radius operation. The method discussed in this document provides cleat envelopment force and moment and tire angular position histories as functions of distance traveled. These histories are essentially free from variations due to tire non-uniformities. The method applies to any size tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire.

This SAE Recommended Practice describes a trio of test methods which determine basic tire size (geometry), mass, and moments of inertia. The methods apply to any tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular surfaces paved or unpaved. Within the context of this Recommended Practice, forces applied to the surface on which the tire is operating are not considered.

This SAE Recommended Practice describes a test method for measuring the forces and moments generated at a spindle when a tire rolls over a rectangular obstacle, cleat, at very low speed. The cleat used in a particular test condition is configured with its crest either perpendicular, 90 degrees, to the path of the tire or optionally with its crest inclined at an angle to the path of the tire. The carriage to which the spindle is attached is rigidly constrained in position during each test condition so as to provide a good approximation to fixed loaded radius operation. The method discussed in this document provides cleat envelopment force and moment and tire angular position histories as functions of distance traveled. These histories are essentially free from variations due to tire non-uniformities. The method applies to any size tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire.

This SAE Recommended Practice describes a test method for determining properties of a non-rolling tire quasi-statically enveloping either a set of triangular cleats or a single step cleat. In the case of the triangular cleats the normal force and vertical deflection of the non-rolling tire are determined. In the case of the step cleats the normal force, longitudinal force, and vertical deflection of the non-rolling tire are determined. The method applies to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire.1 The data are intended for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document, forces applied to the pavement are not considered.

This SAE Information Report presents the background and rationale for SAE J1574-1. The motor vehicle industry is working toward a more complete understanding of the factors affecting the motions of vehicles on the roadway, by using a variety of techniques that predict responses to road and operator inputs. The capability to predict responses is desirable so that vehicles can be designed for optimum safety and utility. In addition to the force and moment properties of the pneumatic tires, a number of vehicle and suspension parameters affect the response of the vehicle; these include weight, center-of-gravity location, moments of inertia, suspension ride and roll rates, suspension kinematic and compliance properties, and shock absorber characteristics. These parameters must be quantified in order to predict vehicle responses. Measurement of most of these parameters will be limited to determining their values in the linear range for use in directional control simulations.

This SAE Recommended Practice describes a test method for determining the vertical force and deflection properties of a non-rolling tire and the associated contact patch length and width. The method applies to any tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this Recommended Practice, forces applied to the pavement are not considered.

This SAE Recommended Practice describes application of two closely related test procedures, which together determine the linear range longitudinal and lateral stiffnesses of a statically loaded non-rotating tire. The procedures apply to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document, forces applied to the pavement are not considered.

This SAE Recommended Practice establishes a rating scale for subjective evaluation of vehicle ride and handling. The scale is applicable for the evaluation of specific vehicle ride and handling properties, for specified maneuvers, road characteristics and driving conditions, on proving ground and public roads. The validity of the evaluation is restricted to the individual ride and handling disciplines defined by these maneuvers and to the particular combination of conditions of the vehicle (e.g., equipment, degree of maintenance) and of the environment (e.g., road, weather). This rating scale may not be suitable for some applications, such as specific types of ride or handling qualities, driver populations and market segments, or for correlating with objective measures. Appendix A - Other Scales discusses rating scales that better suit such applications.

This recommended practice defines methods for the measurement of periodic, random and transient whole-body vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will cause discomfort. Informative appendices indicate the current state of knowledge and provide guidance on the possible effects of motion and vibration on discomfort. The frequency range considered is 0.5 Hz to 80 Hz. This recommended practice also defines the principles of preferred methods of mounting transducers for determining human exposure. This recommended practice is applicable to light passenger vehicles (e.g., passenger cars and light trucks). This recommended practice is applicable to motions transmitted to the human body as a whole through the buttocks, back and feet of a seated occupant, as well as through the hands of a driver.

This SAE Recommended Practice describes a test method for measuring the forces and moments generated at a high frequency response spindle when a rolling tire impacts a cleat. The cleat is configured either with its crest perpendicular, 90°, to the path of the tire or optionally with its crest inclined at an angle to the path of the tire. The carriage to which the spindle is attached is rigidly constrained in position during each test condition so as to provide a good approximation to fixed loaded radius operation. The method discussed in this document provides impact force and moment time histories essentially free from variations due to tire non-uniformities. The method applies to any size tire so long as the equipment is properly scaled to conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development.

This SAE Recommended Practice describes a test method for determining properties of a non-rolling tire quasi-statically enveloping either a set of triangular cleats or a single step cleat. In the case of the triangular cleats the normal force and vertical deflection of the non-rolling tire are determined. In the case of the step cleats the normal force, longitudinal force, and vertical deflection of the non-rolling tire are determined. The method applies to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire.1 The data are intended for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein, road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document, forces applied to the pavement are not considered.

This SAE Information Report presents the background and rationale for SAE J1574-1. The motor vehicle industry is working toward a more complete understanding of the factors affecting the motions of vehicles on the roadway, by using a variety of techniques that predict responses to road and operator inputs. The capability to predict responses is desirable so that vehicles can be designed for optimum safety and utility. In addition to the force and moment properties of the pneumatic tires, a number of vehicle and suspension parameters affect the response of the vehicle; these include weight, center-of-gravity location, moments of inertia, suspension ride and roll rates, suspension kinematic and compliance properties, and shock absorber characteristics. These parameters must be quantified in order to predict vehicle responses. Measurement of most of these parameters will be limited to determining their values in the linear range for use in directional control simulations.