Experimental study of elastic elements of car suspension

Abstract

The smoothness of the ride, handling, directional stability and safety of the vehicle are determined by the parameters of the vehicle's suspension. The vehicle's dynamic performance, comfort level and service life of the chassis elements are influenced by the compliance of the force characteristics of the elastic suspension elements with the calculated parameters.

The article presents the results of an experimental study of the parameters of the elastic elements of the car suspension and the determination of the dependence of the stiffness coefficient on the magnitude of deformation. The theoretical and experimental methods for determining the stiffness of coil springs are analyzed and the choice of a bench method using a strain gauge load sensor is justified. A method for conducting tests with step-by-step loading and unloading of the spring with fixation of the displacement and applied force is developed.

Two rear suspension springs were experimentally investigated - with a constant and a variable wire diameter. For each sample, analytical dependences of stiffness on deformation during loading and unloading were obtained, and the root mean square and relative approximation errors were determined. It was established that a spring with a constant wire diameter is characterized by a more stable (quasi-linear) change in stiffness, while a spring with a variable diameter has a pronounced nonlinear (progressive) characteristic. The presence of hysteresis phenomena was revealed, which cause the difference in force characteristics during loading and unloading.

The article presents the results of an experimental study of the parameters of the force characteristics of the elastic elements of the car suspension using a stand with a strain gauge system for measuring the load. The determination of local values of the stiffness coefficient in the entire operating range of spring deformations, as well as the analysis of the loading and unloading processes is provided by the proposed method, determine the minimum and maximum values of the stiffness coefficient, analyze hysteresis phenomena and residual deformations, and select pairs of springs with similar characteristics for installation on one axle of the vehicle

The results obtained can be used to diagnose the technical condition of springs, select pairs of elements for one axle, optimize design parameters, and adjust vehicle suspension characteristics.