Characteristic of vehicle suspension coil spring : comparison of experiment and finite element method simulation

Coil springs do not always has regular geometry with constant pitch and constant mean diameter. Geometry of spring is more complex. Furthermore, spring stiffness could change with deflection. That makes calculation of spring stiffness more complicated than just putting four values into mathematical formula. In article has been presented two investigation methods of spring characteristic. Investigated object is a passenger vehicle suspension coil spring. Recognition spring characteristic is primary stage of vehicle dynamic suspension simulation. It has a very big impact on the vehicle height, comfort, handling and safety of vehicle. It is often assumed that vehicle spring has constant stiffness coefficient, which is sometimes a reason of incorrect suspension model. Vehicle springs rather has a progressive characteristic than linear. One of presented method is traditional, experimental compression test. Second, one is a measurement and modelling of spring geometry. Than analysing it in finite element method (FEM) simulation. Comparison has been done to check property of FEM process. Computed compression has been done in ABAQUS CAE 6.13-1 software. Analysis has shown that process of analysing is useful. There were obtained a good agreement between experimental research and computed model. In spite of irregular spring geometry, final characteristic is close to linear. Progressiveness is visible but not high.