Rakesh Chandmal Sharma

Analysis of creep force and its sensitivity on stability and vertical-lateral ride for railway vehicle

This paper presents a detailed creep force analysis at wheel-rail interaction using linear creepage-creep force relationship for a 37 DOF model of an ICF coach formulated using Lagrangian dynamics. The mathematical model is validated by simulating PSD vertical and lateral acceleration of carbody and comparing the same obtained from actual testing results. The sensitivity of longitudinal, lateral creep force and lateral/spin creep moment on stability and vertical-lateral ride is analysed. It is found from the present analysis that creep forces are helpful in improving lateral ride and lateral stability for railway vehicles.

Sensitivity analysis of three-wheel vehicle’s suspension parameters influencing ride behavior

In this article coupled vertical–lateral 9 degree-of-freedom model of a three-wheel vehicle formulated using Lagrangian dynamics is presented in order to determine its vertical and lateral ride. The model is justified by correlating the power spectral density vertical and lateral acceleration results determined from analysis with the same obtained from experimental measurements. The ride comfort of the vehicle is evaluated on the basis of ISO 2631-1 criteria. The sensitivity of vehicle suspension parameters on vertical and lateral ride behavior is analyzed, and it is noticed that rear-suspension damping coefficient, front-tire stiffness, rear-tire stiffness, front-tire damping coefficient, and rear-tire damping coefficient are critical parameters for vertical power spectral density acceleration. Rear-suspension stiffness, rear-suspension damping coefficient, front-tire stiffness, and rear-tire stiffness are critical parameters for lateral power spectral density acceleration.

Ride, eigenvalue and stability analysis of three-wheel vehicle using Lagrangian dynamics

This research paper studies the ride behaviour of coupled vertical-lateral 9 degree of freedom model of a three wheel vehicle formulated using Lagrangian dynamics. The mathematical model is validated by simulating PSD vertical and lateral acceleration of three-wheel vehicle sprung mass and comparing the same obtained from actual testing results. The natural frequencies, i.e., eigenvalues of main rigid bodies, i.e., sprung mass, front wheel steering arm and rear unsprung mass of the system are determined through MATLAB simulations. Critical speed of the vehicle is also determined in order to investigate the dynamic stability, and parameters which influence the critical speed are analysed.