Evaluation of Fatigue Life Reliability of Steering Knuckle Using Pearson Parametric Distribution Model

Abstract

Steering module is a part of automotive suspension system which provides a means for an accurate vehicle placement and stability control. Components such as steering knuckle are subjected to fatigue failures due to cyclic loads arising from various driving conditions. This paper intends to give a description of a method used in the fatigue life reliability evaluation of the knuckle used in a passenger car steering system. An accurate representation of Belgian pave service loads in terms of response-time history signal was obtained from accredited test track using road load data acquisition. The acquired service load data was replicated on durability test rig and the SN method was used to estimate the fatigue life. A Pearson system was developed to evaluate the predicted fatigue life reliability by considering the variations in material properties. Considering random loads experiences by the steering knuckle, it is found that shortest life appears to be in the vertical load direction with the lowest fatigue life reliability between 14000–16000 cycles. Taking into account the inconsistency of the material properties, the proposed method is capable of providing the probability of failure of mass-produced parts.

Fatigue Life Evaluation of Suspension Knuckle using Multibody Simulation Technique

“…The ncode Designlife software is used for fatigue life estimation. The suspension of a Proton SAGA is used in this study, and the material of the knuckle considered is FCD500-7 (Azrulhisham et al, 2010). Fatigue properties for the fatigue life simulations are taken from ASTM A-536, which is equivalent to FCD500-7 (GMI, 2012;MP, 2012).…”

“…The knuckle constantly faces time-varying loads during its service life. There are various points of application of structural loads to be applied in different directions at the same time, resulting in complex stress and strain fields (Azrulhisham, Asri, Dzuraidahm, Nik Abdullah, Shahrum, & Che Hassan, 2010). Due to these variable loads it is essential to predict the safe design life of the component in real-world loading conditions (Zoroufi & Fatemi, 2006;Rahman, Ariffin, Abdullah, Noor, Bakar, & Maleque, 2008a;Rahman, Ariffin, Jamaludin, Abdullah, & Noor, 2008b;Rahman, Ariffin, Rejab, Kadirgama, & Noor 2009a;Rahman, Ariffin, Abdullah, Noor, & Bakar, 2009b).…”

Fatigue Life Analysis and Optimization of a Passenger Car Steering Knuckle Under Operating Conditions

“…The length of the beam was taken from the knuckle design as 80 mm and mass of the beam not more than 20% of the existing one to formulate in Eqs. (5)(6). This made the process more effective without increasing the weight while approaching the optimized solution.…”

“…The suspension of modern vehicles needs to satisfy a number of requirements such as loading, driving condition and type of road surface. The steering knuckle is one of the main components used in the McPherson suspension system (Figure 1) in automobiles subjected to millions of varying stress cycles during their life [5]. This demands the thorough study and understanding of the behavior of the steering knuckle under operating conditions.…”

Simulation and Optimization of wheel Hub and Upright of Vehicle: A Review

“…Azrulhisham et al [15] used MATLAB statistical toolbox for calculating probability density function of the Beta distribution of steering knuckle. The function between probability density and fatigue life is shown in fig.-8.…”