Influence of linear leaf springs' hysteresis behavior on vehicle's ride

A method was investigated to select proper damping coefficients of the damper used for the leaf spring suspension, based on the analysis of the influence of leaf springs hysteresis behavior on vehicle's riding on different kinds of roads. Based on a quarter vehicle model, the root of mean squared acceleration of sprung mass was analyzed on different grades of roads with and without consideration of leaf springs' hysteresis behavior. The model was solved in time domain due to its nonlinearities. Both randomly produced road data and a group of real road data were used as inputs of the model. Results show the hysteresis behavior is more harmful to vehicle's riding comfort on a high quality road than on a poor quality road, and therefore the damping coefficients of dampers should be selected according to road grades. For vehicles with leaf spring suspensions, the dampers' damping ratios for jounce travel should be 0.1-0.2 and that for rebound travel be 0.2-0.3.