Virtual Prediction of Tractor Front Axle Load and Fatigue Life in Front Loader Application and Validating with Field Measurements

Abstract

<div class="section abstract"><div class="htmlview paragraph">When a specialty tractor is operated by mounting the front loader or backhoes, the loads are distributed proportionately to the front and rear axles. The maximum load and fatigue life were identified as the main parameters in predicting fatigue failure. This paper mainly focuses on predicting front axle loads and fatigue life in front loader applications.</div><div class="htmlview paragraph">To design a new front axle for the loader application, an existing front axle assembly that was designed for orchard, sprayer, and small farm application is selected for study and to extend it for front loader application with minimal design modifications. The major challenge is to estimate the dynamic loads coming to the front axle due to the front loader application and validate it for a different set of load cases as per the design verification plan. Hence a methodology was framed to estimate the actual loads using MBD, validate with field measurements, and verify the new front axle design using those loads in FEA. This paper discusses this methodology in detail. MBD was performed on a tractor model with an existing front axle assembly for three loader bucket positions. The estimated static loads from MBD are validated with static field measurement data. This estimated load was used in FEA to identify stress hotspot location in the front axle assembly. Strain gauges were used on those hotspot locations to find the maximum dynamic load during actual driving conditions with the front loader application. Design modification has been done on the existing front axle assembly and nonlinear static analysis was performed using the maximum dynamic load to find the maximum stress location and corresponding fatigue life. By this methodology, the existing front axle is modified, simulated with CAE analysis, and validated with field measurement data, which helped us to meet the design acceptance criteria as per DVP for the new front axle design.</div></div>