Modeling and Vibration Analysis of Road Profile Measuring System

Abstract

During a vehicle development program, load data representing severe customer usage is required. The dilemma faced by a design engineer during the design process is that during the initial stage, only predicted loads estimated from historical targets are available, whereas the actual loads are available only at the fag end of the process. At the same time, changes required, if any, are easier and inexpensive during the initial stages of the design process whereas they are extremely costly in the latter stages of the process. The use of road profiles and vehicle models to predict the load acting on the whole vehicle is currently being researched. This work hinges on the ability to accurately measure road profiles. The objective of the work is to develop an algorithm, using MATLAB Simulink software, to convert the input signals into measured road profile. The algorithm is checked by the MATLAB Simulink 4 degrees of freedom half car model. To make the whole Simulink model more realistic, accelerometer and laser sensor properties are introduced. The present work contains the simulation of the mentioned algorithm with a half car model and studies the results in distance, time, and the frequency domain.

Geometrical analysis of profile of certain heavy terrain sections exerting dynamic loads on the chassis components of off-road vehicles

“…Najbardziej popularnym wskaźnikiem porównawczym jest wartość skuteczna RMS zmiany profilu podłoża drogi [1][2][3][4][5]8]. Ważnym narzędziem charakteryzującym zmiany profilu podłoża są charakterystyki amplitudowo częstotliwościowe lub gęstość widmowa mocy (PSD) [3,[5][6][7]9,10]. Takie charakterystyki niosą ze sobą informacje o poziomie oraz strukturze częstotliwościowej wymuszeń kinematycznych działających na koła pojazdu podczas jazdy w warunkach terenowych.…”

“…The RMS of the road surface profile changes is among the most popular indicators used for comparison purposes [1][2][3][4][5]8]. Amplitude and frequency characteristics, as well as the power spectral density (PSD) also serve as important indicators describing road profile changes [3,[5][6][7]9,10]. Such characteristics serve as a source of information on the level and frequency structure of the dynamic loads to which the vehicle's chassis components are subjected to while driving in off-road conditions.…”

Damaging fatigue cycles determination for random service loadings using mixed Weibull analysis

“…One of the obstacles that is the nature of the time series signal of strains in service is often spectrum loadings, irregular and also nonstationary [1,2]. Another fundamental issue is in the extrapolation of complete design spectra from short time measured histories [3].…”

Comparison between vertical acceleration data from acquired signals and multibody model for an off-road vehicle

“…The use of simulations is a prevailing method for the assessment of vehicle projects; however, prediction of loading and reliable structural analysis can only be achieved if there is a faithful model of the vehicle and accurate road data, which fully represent the disturbance absorbed by the car [8]. As for Mini Baja competitions, these are led by engineering students and require time and financial support.…”