Design and Development of Innovative Tyre Test Facilities for Measuring Tyre Characteristics

Tyres play a crucial role in determining the ride and handling properties of a vehicle. Multi-body simulation softwares are being used extensively to understand vehicle ride and handling properties using detailed vehicle models. Models need a set of characteristics and parameters to represent the tyre as close as possible to the actual tyre. Tyre properties are generally grouped into vertical, lateral and longitudinal stiffness characteristics. Various test facilities are currently present in educational institutions and commercial organizations. They are prohibitively expensive to use during product development stage where a number of design iterations are carried out before finalizing for mass production. This paper highlights the work done in creating innovative and simplified test facilities for measuring lateral force characteristics, static vertical, lateral and longitudinal stiffness and dynamic vertical stiffness and damping.

An innovative test facility to measure lateral force characteristics of a tyre has been developed based on fundamental principles of statics and kinematics. The innovative design and on-road measurement methodology ensures that the tyre is subjected to real life situation for measuring the lateral force characteristics. The set up has flexibility to measure lateral forces under various settings of sideslip and camber. User-friendly software has been developed for data acquisition and post processing of data for calculating lateral force due to various slip angles and camber angles. It also enables to perform quick measurements of crucial tyre properties for all the design iterations made during product development instead of measuring the complete set of measurements using expensive test facilities. A test facility for measuring static vertical, lateral and longitudinal stiffness has been developed to study static tyre behaviour by applying fundamental principles of statics. In order to measure tyre properties under dynamic conditions, principles of vibration have been applied to create a facility for measuring the dynamic vertical stiffness and damping. The data acquisition has been made completely automatic with the use of advanced transducers while human intervention is needed only to perform changes in normal loads and tyres.

Simplified and user-friendly design of the test rigs make them highly cost-effective when compared to expensive test facilities available in the market as well as easy to use by any test engineer. All the test facilities have the flexibility to adjust normal loads and accommodate tyres of various sizes. Different kinds of tyres have been tested to study the variation in tyre properties between them. The measured tyre data were given as input to multi-body vehicle model and the response of vehicle to various rider inputs studied and results are presented.