Fatigue life analysis of a special vehicle lower control arm

Abstract To enhance vehicle structural fatigue durability and improve design methods, this study analyzed and predicted the fatigue life of a special vehicle control arm. Finite element analysis was used to model the control arm, identify stress hot spots, and determine fatigue damage locations. Strain loads under test conditions were measured, and data processing, including spectrum analysis and low-pass filtering, was performed to create a load spectrum using the rain flow counting method. Fatigue life and damage were analyzed using the nominal stress method and Miner’s criterion in Ncode software. Results show that the fatigue damage distribution matches actual road conditions, with an expected life of 21, 200 hours, meeting usage requirements.