Strength Analysis of MEvITS (Multi-purpose Electric Vehicle ITS) Ladder Frame Type Due to Static and Dynamic Loads on Life Fatigue

The strength of the vehicle chassis structure is designed to be able to withstand the load that is applied to all sub- components of the vehicle and its cargo. Therefore, there is a need to select the use of the appropriate chassis structure. This study aims to analyze the performance and safety under static and dynamic load parameters that affect the fatigue life of the MEvITS ladder frame chassis structure. The static load analysis is done by applying the load of all vehicle component weights and also the torsional load. Loading of vehicle weight components is carried out to determine areas that experience maximum stress and a small critical point of safety factor. The torsional load is applied to determine the torsional stiffness by applying equal force values to the two front suspension brackets in the reverse direction, the positive and negative vertical axes. The dynamic loads are performed by applying random excitation to the chassis from road roughness according to ISO 8606. Random vibrations are performed to analyze the response of the chassis from random excitation to determine the fatigue factor of the chassis. Modal analysis is also carried out as input in the random vibration of the natural frequency and the shape of the chassis modes. 3D modeling design of the MEvITS chassis is using Solidworks. The static structural analysis, torsional load, modal analysis, and random vibration are performed in Ansys software. The MEvITS chassis has a safe condition under static loads with a safety factor of 1.3038. Besides that, the MEVITS ladder frame chassis also has low torsional rigidity with a value of 985.488 Nm/deg. then dynamic loading, the chassis shows good performance to resist random excitation. The factor of safety from fatigue due to random excitation is 73.