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Structural durability of automotive components is one of the key requirements in design and development of today’s automobiles. Virtual simulations are used to estimate component durability to save the cost and time required to build the components and testing. The objective of this work is to find the service life of automotive HVAC pipe assembly by calculating cumulative fatigue life for operation under actual powertrain load conditions. Modal transient response analysis is performed with the measured powertrain load time history. Strain based fatigue life analysis is carried out using modal superposition method (MSM). The estimated fatigue life was compared with the physical test results. This paper also explains the root cause of low fatigue life on pipe assembly and provide the solution.

Vehicle suspension parts are subjected to variable road loads, manufacturing process variation and high installation loads in assembly process. These parts must be robust to usage conditions to function properly in the field. Design for Six Sigma (DFSS) tools and Taguchi Method were used to optimize initial rear suspension trailing arm design. Project identified key control factor/design parameters, to improve part robustness at the lowest cost. Optimized design performs well under higher road loads and meets stringent durability requirements. This paper evokes use of Taguchi Method to design robust rear suspension trailing arm and study effect of selected design parameters on robustness, stress level/durability and part cost.

Strength and fatigue assessment of chassis components are essentially influenced by the material used and manufacturing processes chosen. The manufacturing process of chassis components decides the variation in the mechanical properties of the component, which has an impact on the strength/fatigue performance. Investigating the design concerning the manufacturing processes is vital to the industry. Standard computer aided engineering (CAE) procedures for validating the alloy wheels usually consider the material properties as homogeneous. There was a gap between test results and CAE durability prediction (as per standard procedure). Incorporating the manufacturing process related characteristics with the strength simulation will be a viable solution to reduce this gap. This study was intended at developing a procedure for the strength analysis of an alloy wheel by considering the manufacturing process.

Structural durability of the vehicle components is one of the key factors in design and development. This helps in understanding the capability of structures or components to withstand the loads encountered in service over a specified period of use. Durability assessment for vehicle structures requires load inputs. These load inputs can be in form of force, acceleration and displacement and typically generated from road load profiles in the testing lab or by the load groups. But if a program is in its early stage when design data is immature or lab facility is limited then acquiring these load inputs takes time and sometimes not feasible also. In this scenario, we can predict the durability load inputs from road load profiles virtually using dynamic transient simulation. The objective of this work is to predict the durability input signals from road profiles using finite element model by modal transient approach.

Brakes are the critical component, plays a significant role regards to performance of vehicle. Vehicle safety is also strongly influenced by proper braking operation, which depends on pad to disc contact interface. Pad and disc surfaces are worn out due to continuous braking events, which in turn affects the life of the brake assembly and its performance. This paper presents the brake pad wear prediction of a disc brake assembly. A new and unworn pair of brake pads are considered for the study and tested under different braking scenarios. Wear simulation procedure is formulated based on Rhee’s wear formula and wear calculation model is established based on friction and wear mechanism. The correlation between the wear behavior of a friction material tested under controlled laboratory conditions and finite element method is investigated. Based on the calculated wear, lifespan of the brake pad is also calculated.

Brake moan noise is a friction induced phenomenon occurring at very low brake pressure, speeds and in the frequency range of 100-500 Hz. Moan noise is induced due to stick-slip phenomenon between brake rotor and pad. In this paper, prediction of moan noise with complex eigenvalue method along with other static steps is described. The complex eigenvalue is performed in multiple steps of analysis. Pretension analysis followed by nonlinear static analysis (For brake pressure and rotor velocity) is performed to provide a sliding motion between the pads and the disk. From the pre-stressed condition at the end of the static analysis, the tangent stiffness matrix is found out by linear perturbation method and followed by that complex eigenvalue analysis also performed. From the eigenvalue analysis, instability modes and the corresponding mode shapes of the brake assembly are calculated by considering the nonlinear effect of loading and contacts.

Vehicle suspension parts are subjected to variable road loads, manufacturing process variation and high installation loads in assembly process. Seam welding can be considered as such process to connect more components and parts. Typical in a Mc Pherson suspension system stabilizer bar link is connected to the strut assembly through ball stud and clamped to a bracket welded to the outer strut tube. Cracks have been observed in the stabilizer bar link bracket welds of vehicles in the field, effecting the functionality of the suspension system. During preliminary phase of product development CAE assessment of the seam weld is carried out against road load data, if the design does not meet the targets enabler studies are carried out in an iterative approach. Various design variables (control factors) can be considered to carry out the iterations.

Brake assemblies are an essential part of any vehicle, and their effective functioning is critical for the safety and comfort of passengers. The surface roughness of brake components plays a vital role in figuring out their tribological and NVH (Noise, Vibration, and Harshness) behavior. It is essential to understand the impact of surface roughness on brake performance to ensure efficient braking and it has been a topic of interest in the automotive industry. In this study, the influence of surface roughness on the wear, and noise characteristics of a brake assembly has been investigated. The study also provides insights into the relationship between surface roughness, frictional behavior, and NVH performance, which can be used to improve the design and manufacturing of brake assemblies. The brake assembly includes of a disc, caliper, and brake pads, which work together to convert the kinetic energy of the vehicle into heat energy, has been considered in this study.