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With the increase in demand for energy sustainability projects over the last few years, the Brazilian commercial vehicle industry was guided to develop projects based on ESG policies. Aligned with this need, an initiative that ended up becoming a reality was the “e-Sys” electrification solution, by the company Suspensys. This solution includes a power source (battery), an e-powertrain (motors, inverters and drive axle) and an intelligent control system (VCU with embedded code and sensors). The main motivational drive was the hybridization of semi-trailers, in order to generate a reduction in fuel consumption in cargo transport in Brazil, in addition to the consequent reduction in the emission of particles into the environment and promoting the safety of the operation. It was also adopted, as a premise of the project, that the electrification system was totally independent of the truck’s electronic system (stand alone system), in order to facilitate the operation of the fleet owner.

With the announcement of the Euro 7 proposal, it is now clear that nitrous oxide (laughing gas, N2O) emissions must be considered and complied with the certification of exhaust aftertreatment systems (EATS) of commercial vehicles (CV). This paper describes the possible formation pathways for N2O in the EATS for different drives and uses measurement results to show the boundary condition and the magnitude of formation as well as the possibilities for influencing or preventing its formation.

In order to evaluate the THOR-50M as a front impact Anthropomorphic Test Device (ATD) for vehicle safety design, the ATD was compared to the H3-50M in matching vehicle crash tests for 20 unique vehicle models from 2 vehicle manufacturers. For the belted driver condition, a total of fifty-four crash tests were investigated in the 56.3 km/h (35 mph) front rigid barrier impact condition. Four more tests were compared for the unbelted driver and right front passenger at 40.2 km/h (25 mph) in the flat frontal and 30-degree right oblique rigid barrier impact conditions. The two ATDs were also evaluated for their ability to predict injury risk by comparing their fleet average injury risk to Crash Investigation Sampling System (CISS) accident data for similar conditions. The differences in seating position and their effect on ATD responses were also investigated.

With the law on autonomous driving and the associated ordinance, it has been possible in Germany since June 2022 to grant operating permission to vehicles with automated driving function and to admit them to road traffic. For public transport, automated shuttle buses offer the opportunity to maintain the existing service despite a shortage of personnel and to close gaps in supply. The safety of vehicle occupants, other road users and third parties is a key concern in the operation of automated shuttle buses. As part of the project RABus “Real laboratory for automated bus operation in public transport in urban and rural areas”, which is funded by the Ministry of Transport Baden-Württemberg, the operational reliability of automated shuttle buses (SAE Level 4) in public transport is being scientifically investigated. In the implementation of automated driving, obstacle detection/avoidance is a safety-critical driving function.

With the introduction of the emission legislation Euro VI for commercial vehicles (CVs), selective catalytic reduction (SCR) with urea water solution (UWS) as the reducing agent has become a standard to minimize the nitrogen oxides (NOx) emissions from internal combustion engines. The urea processing and mixing unit has been developed and optimized in order to avoid deposit formation and ensure a high level of urea processing over the whole operation range, especially at lower temperatures. However, there are physical limits to the conversion of urea in conventional processing units during very low engine operating conditions. With the EHC Fractal Heater, Purem by Eberspächer has developed a heating measure that, in addition to its main function of accelerating the light-off of catalytic converters, also comes with the possibility of improving the UWS processing, especially under these low-load conditions.

Due to the emerging technologies and globalization, expectations of the customers on commercial vehicles are getting increased over the period. It is an important duty of an OEM to deliver a perfectly configured product to suit the customer requirements. When it comes to configuration of a vehicle, engine power is one of the key factors which indicate the performance of that vehicle. There is a tough competition between every OEM to increase the engine power for enhancing the overall operational performance. One method to increase power is to improve its volumetric efficiency. This is achieved with help of turbocharger and Charge Air Cooler (CAC). CAC improves volumetric efficiency by increasing intake air-charge density. Any failure on CAC leads to lower the volumetric efficiency and increase in turbocharger loading. This paper deals with the validation of CAC assembly using different test conditions by analyzing potential failure modes against the field issues.

The Tractors are inevitable in the world due to its remarkable contribution majorly in farming process and other applications. the farming equipment needs to perform multiple applications to enhance the productivity and increased horsepower demands all-wheel drive (Refer fig. 1) or four-wheel drive option in the tractor. So, it is becoming a mandatory feature. The main objective of this study is, improving the torsional fatigue life in front axle spindle shaft by modifying the spline design and optimizing induction hardening heat treatment process in such a way that the other part of the system will have a minor or no design change. It helps us to reduce the part count variability, lower manufacturing cost and development time.

Leaf springs are used for vehicle suspension to support the load. These springs are made of flat sections of spring steel in single or in stack of multiple layers, held together in bracketed assembly. The key characteristics of leaf spring are defined as ability to distribute stresses along its length and transmit a load over the width of the chassis structures. The most common leaf spring steels are carbon steels alloyed with Cr and micro-alloyed with Ti, V and Nb. The specific thermomechanical process and alloying elements result in specific strength and fatigue properties for spring steels. The unique properties which facilitate use of spring steel in leaf spring suspensions are ability to withstand considerable twisting or bending forces without any distortion. The microstructure of these steel determines the performance and reflects the process of steel manufacturing. The performance is mainly determined by evaluating fatigue life durability.

Materials play a key role in our day to day life and have shaped the industrial revolution to a great extent. Right selection of material for meeting a particular objective is the key to success in today’s world where the cost as well as sustainability of any equipment or a system have assumed greater significance than ever before. In automotive industry, materials have a definitive role as far as the mobility and safety is concerned. Materials that can absorb the required energy or impact can be manufactured through different manufacturing as well as metallurgical processes which involves appropriate heat treatment and bringing correct chemical compositions etc. However, they can also be formed by simpler methods such as combining certain materials together in the form of layered combinations to form light weight composites.

The dump body of the off-highway dump truck is the large, prime structure, used to carry overburden and coal in mines. The body structure is subject to severe vibration, impact load, and oscillation events due to rough terrain conditions in the mines and the loading of rocks from a certain height from the shovel. Presently, the body mounting design is chassis pivot pin mounted, rubber rail seated, and has guide plates to lock transverse movements. Despite all these mounting arrangements, the body structure oscillates (or rattles) due to multiple field factors. The most effective solution to the problem is to provide an additional oscillation-arresting structure so that body stability is achieved and undesirable body-frame impact is avoided.

Fuel tank is considered as safety component in the vehicle, and it has to be tested to meet the safety requirements as per AIS 095. Earlier, fuel tanks were manufactured by using Hot dipped cold rolled steel material and the weld zones are applied with Anti-corrosive coating. Few fuel tanks were reported with Corrosion problems. The root cause analysis was carried out considering the raw material, manufacturing process, transpiration, storage and usage. As an improvement, the new fuel tank is designed to eliminate the limitations of the existing fuel tank. 3D modeling was done to check space and mounting requirement in the layout and used for volume calculations. FE analysis was performed to check structural stability. Emphasis given on Interchange-ability to cater the new fuel tanks in place of old as spares requirement. The fuel tank has developed with Alumina steel material.

Motor grader is self-propelled, versatile machine widely used for road construction and maintenance in mining and construction applications. It required working in rugged terrain with uneven and slippery surfaces. Probability of rollover in motor grader is more due to the vehicle profile and high centre of gravity. In light of the above, Roll over Protective Structure (ROPS) is essential to safe guard the operator from any fatal injuries / life during the operation of the equipment at different terrain conditions. Considering DGMS (Directorate of General Mines and safety) requirements, a rugged two post Rollover Protective Structure (ROPS) was designed as per ISO 3471 criteria for ROPS and Falling object Protection Structure (FOPS) as per ISO 3449 Material selection for ROPS and FOPS is one of significant factor in design process by meeting the design criteria. It should have dual characteristic, firstly, it is expected to tough enough to withstand sudden impact forces.

Globally, automotive sector is moving towards improving off-road performance, durability and safety. Need of off-road performance leads to unpredictable overload to powertrain system due to unpaved roads and abuse driving conditions. Generally, shafts and gears in the transmission system are designed to meet infinite life. But, under abuse condition, it undergo overloads in both torsional and bending modes and finally, weak part in the entire system tend to fail first. This paper represents the failure analysis of one such an incident happened in output shaft under abuse test condition. Failure mode was confirmed as torsional overload using Stereo microscope and SEM. Application stress and shear strength of the shaft was calculated and found overstressing was the cause of failure. To avoid recurrence of breakage, improvement options were identified and subjected to static torsional test to quantify the improvement level.

Spiral bevel gears are commonly used in heavy-duty trucks and buses. An integrated dynamic model of the spiral bevel gears with mixed elastohydrodynamic lubrication is proposed in this study. First, loaded tooth contact analysis was performed to evaluate the kinematic parameters and calculate the mesh force variation for one mesh cycle. These kinematic quantities are used in the mixed elastohydrodynamic lubrication (EHL) calculation to determine the EHL parameters such as pressure, film thickness, and shear distribution considering the surface roughness profile of the spiral bevel gears. Then, the EHL pressure and film thickness are used in the calculation of the coefficient of friction, damping, and oil film elastohydrodynamic lubrication stiffness. Last, these tribological parameters are used in the dynamic calculation of the spiral bevel gears.

NVH (Noise, Vibration and Harshness) of the electric drive axle (EDA) is a key attribute in electric-vehicle development. The NVH attributes of the EDA directly determines the driving comfort and customer feeling of the vehicle. Especially in pure electric working condition, the EDA noise is more perceptible by people without the engine noise masking. This paper investigates the abnormal noise in the vehicle caused by EDA. First, the filtered playback method is used to identify abnormal noise frequency between 330Hz and 430Hz.Adopted modal analysis, MASTA simulation, modulation noise analysis to identify problematic critical parts. The validity of the results is verified using the DOE method by part exchange, and finally locked to the source of gear parameters Rs and Fr. By adjusting the production process of gear and the second shaft, the assembly process error was avoided, and the gear parameter targets are formulated.

Increase in comfort requirements for noise and vibrations in commercial vehicles, demand for identifying major NVH issues and addressing them at design stages, thereby avoiding cost incurred due to design changes in later stages of the product development. This work majorly focusses on establishing an approach for predicting NVH performance of a heavy-duty truck using frequency response function based sub-structuring (FBS) methodology. This approach helps in reducing the overall solving time, specifically while analyzing for truck finite element models with large number of degrees of freedom. It majorly involves representation of all subsystems of a truck in the form of frequency response functions. A detailed finite element model of a full truck is evaluated for NVH load cases such as vibration / noise transfer function studies and operational NVH load cases such as vehicle idle and dynamic gear run-ups.

A typical cab used on agriculture machines is made up of a metal frame structure with large enclosing panels of glass, plastic, and metal. Acoustic treatments such as coatings, textiles and foams are used within the cab for aesthetics but also to mediate undesired noise. To develop effective designs for the cab to combat noise, accurate tools for measurement, and predictive methods for sound transmission loss are needed. This paper focuses on Sound Transmission Loss (STL) of the rear upper panel of a cab used in agriculture machines. Results from CAE based tools such as Statistical Energy Analysis (SEA), Finite Element Analysis (FEA) and Hybrid FE-SEA methods are compared to measurements. The panel studied included features such as curvature, deep drawn beads with a glass window and a damping coating. The simulation results are refined by incorporating methods for accurate modeling of ribs stiffness, curvature effect and radiation efficiency by synthetic modal approach.

This paper investigates the problem of whine in the E-axle (Electric Drive Axle) system during acceleration of a light bus. The problem is identified as motor and reducer whine by the noise spectrum feature analysis method. Under the condition of ensuring motor performance and low cost, the motor whine is solved by optimizing the air tightness and sound insulation of the vehicle. Starting from gear microscopic shaping research, gear manufacturing and assembly process optimization was used to control gear whine. After testing and analysis, the means to effectively solve the E-axle system whine problem. The whine noise is optimized by about 8 dB (A). The results provide key technical support for the smooth production of the vehicle. It has certain guiding significance for the NVH (Noise, Vibration and Harshness) performance design and development of the E-axle system project.

HVAC system design has an accountability towards acoustic comfort of passengers of a vehicle. Owing to larger cabin volume of a bus, multiple air blowers have to be installed to ensure comfort of passengers. Such multiple blowers produce significant flow induced noise inside the cabin. For commercial success, it becomes essential to predict intensity of such a flow induced noise at very early stages in product development. Conventionally sliding mesh based CFD approach is deployed to predict flow and turbulence noise around each blower. However due to complexity, this method becomes computationally intensive resulting in cost and time inefficiency. Hence it is desirable to innovate around an alternative rapid, reliable prediction method, which ensures quick turnaround of prediction.

Engineering of solutions for vibration challenges consists of several steps. Each of them needs different methods, for most steps, several approaches are valid. This work describes one efficient way to get from customer wishes over calculation methods and experimental results as far as the lifetime calculation. The example is an all-metal cushion used as a spring-damper system, that solves vibration problems of the suspension of an electrical drive for a commercial vehicle used in a city. Metal cushions for vibration isolation are used where high dynamic stresses occur or the environmental conditions overwhelm rubber solutions. So, they are a perfect solution for vibration isolation in industrial environments as well as in railway, automotive and aerospace sectors. Additionally, the progressive stress-deflection behavior and the high damping offer advantages for a wide range of applications.