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In the automotive industry, the electric vehicle is the new era, and companies are committed to reducing carbon emissions by electrification of their vehicles. In the development of electric vehicles, the battery is the central power source for all the parts of the vehicle. Usually, it is placed under the body because of its size and mass. So, it is important to protect battery cells from leakage and damage from obstacles. For on-road electric vehicles, speed bumps are one of the crucial obstacles. This paper investigates and analyses the protection of battery pack systems in electric vehicles while encountering speed bump profiles at different speeds. During the physical test on a speed bump, there is a possibility of bump hit on the battery pack system and it is necessary to ensure the structural safety of the battery pack systems. In this study, CAE method has been developed to validate the battery pack system in the event of a speed bump crossing.

Powertrain wiring cable is a backbone of the electrical architecture in any vehicle electrical system design. The weight of a wiring cable is increasing year by year because of the recent development on high-voltage wiring systems, hybrid electric vehicles (HEVs) and electric vehicles (EVs). Clip failure, loosening clip and terminal breakage under engine roll condition is a common issue in powertrain electric cable (or body harness routing) development cycle in automotive industry. Usage of more number of clips in cable routing results in the powertrain design being more complex and it increases manufacturing cost. The standard procedure practiced to develop any dynamic envelope is by using CAD software tools and performing rigid body movements with the help of the motion file.

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.

Roof is one of the major subsystems of the Body-In-White Structure, which significantly affects the vehicle strength and durability performance criteria. The roof structure should meet the functional targets under the standard operating conditions. Roof design considering various parameters in the initial phase is beneficial in reducing the product timeline for the OEM. The first-time right approach provides an opportunity for Optimization and Cost benefits in the longer term. This paper provides the use of Design for Six Sigma techniques to arrive at a robust and optimum design for the standard roof structure. The roof structure is designed to meet the operating conditions for durability. Roof finite element models are developed with control factors that affect the structure design. Virtual Analysis is performed on the Standard roof structure models.

In the automotive industry, the structural evaluation of suspension systems under customer abusive loads (misuse loads) is essential. The vehicle may experience the abusive loads in fore-aft, lateral and vertical directions. From a design perspective, it is crucial that the suspension should be robust enough to withstand the abusive loading due to maneuvers on various terrains. The main challenge during virtual simulation of these load cases is the time required to complete the assessment. The current method involves a detailed suspension finite element (FE) model which takes considerable computational and post processing time. Any kind of manual mistakes will further increase assessment time. The time becomes even more crucial when the product is in the final stages of the development process where quick turnaround is required.

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.

In the automotive industry, the development of suspension systems for misuse loads is essential. The vehicle may experience the abusive loads in fore-aft, lateral and vertical directions. From a design perspective, it is crucial that the suspension should be robust enough to withstand the abusive loading in different directions. Testing as well as virtual simulation of the suspension for feasible misuse scenarios can provide a desired design solution in the most optimized time. Better Virtual simulation practices provided with good modeling strategy and detail material model data can help to anticipate the accurate response of the system, which can benefit to reduce the number of physical tests. This paper describes an explicit dynamic approach to predict the behavior of suspension system under impact load condition. Material failure model is proposed to simulate the failure of parts and change in load path under high loading condition

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.

There is an increasing demand for reducing vehicle development process and minimizing cost due to tough competition in Automotive market. One of the major focus areas is minimizing the vehicle proto build that are required for physical testing during vehicle development. Tow hooks are key structural components for the vehicle, which are designed to withstand structural strength performance under various vehicles towing condition. Typical extreme load scenario for the vehicle can be towing fully loaded vehicle breaks down on uphill road or stuck in wet muddy condition. To exercise the tow hook structural development in early design phase, it is important to have reliable simulation process. This paper focuses on development of virtual test simulation process that replicates the tow hook system test behavior for the operating load. The study includes the detail modeling of clevis load applicator, tow hook, bolt joint and attached test bed plate for capturing the load path.

In current scenario, there is an increasing need to have faster product development and achieve the optimum design quickly. In an automobile air conditioning system, the main function of HVAC third row floor duct is to get the sufficient airflow from the rear heating ventilating and air-conditioning (HVAC) system and to provide the sufficient airflow within the leg locations of passenger. Apart from airflow and temperature, fatigue strength of the duct is one of the important factors that need to be considered while designing and optimizing the duct. The challenging task is to package the duct below the carpet within the constrained space and the duct should withstand the load applied by the passenger leg and the luggage. Finite element analysis (FEA) has been used extensively to validate the stress and deformation of the duct under different loading conditions applied over the duct system.