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The hybrid structure of Engine Mounts made of rubber casing with cast iron reinforcing. Use of two materials made it unique both in application and testing. The rubber provides damping for engine vibrations and the cast iron provides necessary strengthening to hold the heavy engine in place. In this research paper the FEA (Finite Element Method) methodology is being discussed to evaluate and optimize the design analysis to enhance overall engine mount capacity. The existing and modified designs are validated and considerable improvement is being observed in modified design in physical testing. Accurate modeling of engine mounts assembly is presented in this paper. FEA analysis results have good correlation with physical validation for both designs. Impact of design parameters of rubber mounts has been presented.

In an electric vehicle, engine is replaced with battery and transmission is replaced with traction motor. Thermal management of electric battery and motor became a necessary evaluation step in the design and development process of electric vehicles. The temperature of the traction motor coolant is required to be maintained below 600C to ensure proper functioning of the system. Coolant takes away heat from traction motor, motor controller along with an on-board charger in battery charging and discharging conditions. In this paper the cooling unit selection for the total required heat rejection from all three components is analytically calculated and thermal management methodology of liquid-cooled Electric Motor is being studied and documented with the help of numerical simulation. The results are further validated with test results in Electric bus for city application.

With the significant amount of automation and electrification paving the way for the future of automobiles, the complexity and design of the electrical harnesses have evolved to a point where a minuscule discontinuity can cease the operation of a mechanically pristine vehicle. A vehicle equipped with the best-in-class systems does not always guarantee everlasting operations every time. The wiring harness of any vehicle by its design aspect is one of the most crucial and vulnerable components. Prone to succumbing to factors such as electrical overloading, physical impact, unprofessional handling, and even sabotage, presently there lies no backup system to compensate for the loss of functions of the main electrical network in the event of a failure. In the interest of rapid re-instating of primary functions in a vehicle to make it operational in the event of an electrical failure, the concept of an emergency piggyback electrical network is delineated.

With the enforcement of ever stringent emission norms, vehicular subsystems are witnessing a substantial transition from electro-mechanical to electronic control-based systems. With the inclusion of incremental modifications to be suitable for future applications, the electrical system has reached a point where it is undergoing a major transition. Further catalyzing this reform is the demand for mass passenger safety, bringing about its own set of uncompromising norms. While the implications of the regulations enforce cleaner and safer mobility, there also arises a conflict between vehicular functionality and safety. This paper enumerates on the first-hand experience of how the direct transfer of the elementary vehicle battery isolator from the prior euro-4 electrical system to the present euro-6 system resulted in a disharmonized vehicle operation when made to comply with both functionality and passenger safety norms.

Engine mounts are an integral part of the vehicle that helps in reducing the vibrations generated from the engine. Engine mounts require a simple yet complicated amalgamation of two very different materials, steel and rubber. Proper adhesion between the two is required to prevent any part failure. Therefore, it becomes important that a comprehensive study is done to understand the mating phenomenon of both. A good linking between rubber and metal substrate is governed by surface pretreatment. Various methodologies such as mechanical and chemical are adopted for the same. This paper aims to present a comparative study as to which surface pretreatment has an edge over other techniques in terms of separation force required to break the bonding between the two parts. The study also presents a cost comparison between the techniques so that the best possible technique can be put to use in the commercial vehicle industry.

Range of an electric vehicle is one of the most prominent decisive factors for a person willing to buy an electric vehicle. In this paper an algorithm is developed to estimate the load carried by the truck or passengers in case of a bus and accordingly switch between ECO, ECO+, Normal, Power, and Power+ modes. This is similar to the ECO/Power switches available in the vehicles, but here auto switching is done to reduce driver dependability and allow vehicle to operate in 5 different modes without driver intervention. Optimum utilization of available torque is done for efficient operation of the vehicle in all load and road conditions. The model-based software development using MATLAB Simulink is used to develop an algorithm which will switch to Power or Power+ torque mode if the vehicle is fully laden or if the vehicle is going on a steep hill, whereas the algorithm will switch to ECO+ or ECO mode if the vehicle is empty or carrying less load.

Electric vehicles have a limitation of limited range and long charging time. Energy optimization plays a very crucial role in determining the range of an electric vehicle. The innovative system proposed here gives the opportunity to reduce energy wastage and efficiently direct the electrical energy to improve the driving range of a 9 meter AC electric bus. The high voltage air conditioner unit alone consumes more than 40% of the electrical energy stored in the traction battery which reduces the driving range of the electric bus drastically. The proposed system optimizes the air conditioner utilization to direct cool air only in areas where passengers are present. Buses do not always run on full capacity, when there are less number of people in the bus the system detects the locations of the passengers using sensors and occupant detection algorithm, this enables the controller to identify the areas where cooling has to be focused and where cooling can be reduced or stopped.

This paper focuses on partial encapsulation technique for reducing air-borne noise from the rocker cover of a commercial vehicle diesel engine. Due to increasing awareness, customers demand for improvised NVH (Noise Vibration and Harshness) performance in modern day vehicles. Better NVH performance implies better comfort for passengers as well as vehicle operator. This further increases the driver up time due to reduced driver fatigue. In order to improve NVH performance of existing vehicle and observe different noise and vibration zones, detailed noise and vibration mapping was carried out on one of our vehicle platform. It is observed that engine noise is one of the major contributors for interior noise, apart from road inputs etc.

In today’s automobile industry refined NVH performance is a key feature and of high importance governing occupant comfort and overall quality impression of vehicle. In this paper interior noise and vibration measurement is done on one of the light truck and few dominant low frequency noise booms were observed in operation range. Modal analysis was done for the cabin at virtual as well as experimental level and few modes were found close to these noise booms. Vibrations were measured across the cabin mounts and it was found that the isolation of front mounts is not effective at lower frequencies. Taking this as an input, the mount design was modified to shift the natural frequency and hence improve the isolation behavior at the lowest dominant frequency. This was followed by static and dynamic measurement of the mounts at test rig level to characterize the dynamic performance and stiffness conclusion.

Passenger vehicles are used as one of the frequently used and versatile mode of transport. Commercial buses cater to short to long distance travel for city as well as highway applications. Thus, passenger ride comfort becomes paramount for the salability of the vehicle. Generally, it is observed that the rear seat experiences the worst ride comfort characteristics due to rear overhang and pitching characteristics of buses. Therefore the objective of this project is to improve the rear seat vibrations of passenger bus by tuning damper characteristics. Shock absorbers, being a low cost and easily interchangeable component is tuned first before optimizing other suspension parameters. The methodology is as follows: first, a 4 degree of freedom mathematical model is created on MATLAB Simulink R2015a environment. Time domain data is obtained by road load data analysis and used as an input for the mathematical model.

In recent times there has been rising demand for noise level reduction in commercial vehicles. Vehicle engine exhaust system is one of the key sources of noise at driver ear, especially in smaller wheel base vehicles, as well as critical for meeting pass by noise regulations. Several techniques are used to reduce the noise level of an exhaust system such as resonators, dissipative mufflers for low & high frequencies respectively. In this paper sound transmission loss (STL) measurement for a LMD bus exhaust system was carried out at rig level. It has been found from the measured data that noise attenuation of current exhaust system is poor in low frequency zone & therefore lower STL frequencies were identified. To attenuate the noises at identified frequencies Helmholtz resonator was introduced, which is particularly effective for low frequency noise attenuation.

With rising concerns on internal combustion engine noise levels in commercial vehicles, it is necessary to attenuate noises present in specific frequency bands. This can be achieved with the implementation of a quarter wave tube on the present exhaust system. Historically such passive attenuators have been efficient only at specific engine speeds and exhaust gas temperatures. A new folded adaptive quarter wave tube design is proposed here which can give significant noise attenuation at various engine operating conditions. The proposed design eliminates the requirement of complex electronic actuating mechanisms for the adaptive quarter wave tubes and replaces the same by perforated diaphragms and adjustable end plates, which are more robust and effective. The module can replace the turbo S-flow single chambered muffler which is installed on most of the commercial vehicles. A design is conceptualized and developed using CAD tools.

Present day truck cab suspension comprises fully floating linkage type cab suspension to facilitate ride comfort. Fully floating cab has certain limitations in terms of stability of cab in dynamic articulations during vehicle running especially in off-road terrain applications. Presence on linkages leads to more wear and tear of joints and bushes which will in turn provide detrimental effect on vibration levels of cab that affects ride comfort for occupants. There is a dire need to develop a system that provides improvement in lateral and vertical stability of cab without compromising ride comfort of occupants. Durability of the product also to be met till life of vehicle. Anti-Vibration Stability Cab Mount is an unsymmetrical mount designed by compounding of elastomeric(rubber) metal bonded outer sleeves sandwiched between multistage inner mount bonded on aluminum casing. Cabin front supports are hinged to mount along with housing providing proper alignment to cab after assembly.

Vehicle life and performance is affected by many factors when in use. The most influential being the vibrations generated especially when the vehicle is in motion. These vibrations are directly experienced by the driver, whose performance goes down, if under continuous influence of these vibrations. This increases the fatigue and greatly reduces the return on investment done by the customer. There are two major sources of vibrations, the engine and the road on which the vehicle moves. To prevent such issues engine mounts are used in vehicles, which may seem simple but perform a critical role, of providing comfort to the driver. Therefore, it becomes important that thoroughly designed and examined mounts are being used in the vehicle. This paper focuses on the methodology to be followed for design and validation of an engine mount used in heavy duty vehicles.

Seats are one of the critical component of school bus for children’s comfort & safety. Seat foam thickness, its shape, cushion width & seat height will play a vital role in comfort. Fatigue is the common cause due to uncomfortable seating and it is due to only one type of seat available in school buses to accommodate different height children. (here different height means; schools have children from class nursery to senior secondary). Fatigue will cause impact on children’s health & overall development. The topic was chosen because of increasing concerns in children’s comfort & safety in school buses. In existing design, standard seat with cushion height from bus floor is 450mm. In this case, it’s only suitable for children height of 4.5 feet to 5.5 feet. Ergonomically, it is very difficult to climb on the seat for range of children height from 3 feet to 4feet.

In the view of an eco-friendly environmental future, the major automotive manufacturers are making a move towards electric mobility. The electric vehicle helps to achieve Zero-emission. However, there are some limitations too. The zero-emission Battery electric vehicle (BEV) can provide a limited range only; the market penetration is getting difficult because of an energy storage capability. The addition of an electric vehicle with a fuel cell unit and a hydrogen supply unit can increase the range and the energy capacity of the system. Fuel cell electric vehicle (FCEV) system is faster to refill compared to plug-in Battery electric vehicle (BEV). This study deals with a behavioral analysis of Polymer Electrolyte Membrane (PEM) Fuel cell; with different drive cycles. In this, a fuel cell model developed and simulated in the SIMULINK environment with different drive cycle and results were obtained. The fuel cell controls also were analyzed for the city start/stop cycle.

Ride Comfort forms a core design aspect for suspension and is to be considered as primary requirement for vehicle performance in terms of drivability and uptime of passenger. Maintaining a balance between ride comfort and handling poses a major challenge to finalize the suspension specifications. The objective of this project it to perform ride- comfort analysis for a commercial truck using MATLAB Simulink. First, benchmarking was carried out on a 4x2 commercial truck and the physical parameters were obtained. Further, a mathematical model is developed using MATLAB Simulink R2015a and acceleration- time data is collected. An experimentation was carried out on the truck at speeds of 20 kmph, 30 kmph, 40 kmph and 50 kmph over a single hump to obtain actual acceleration time domain data. The model is then correlated with actual test over a single hump. This is followed by running the vehicle on Class A, B & C road profiles to account for random vibrations.

In the current commercial vehicles market, ride-comfort and handling are crucial parameters for the customer and end user. There are various aspects which determine the vehicle behavior. One of aspects is the structural rigidity of the vehicle, which has its own effect on vehicle dynamics. To meet the required stiffness of the main structural component of the vehicle i.e. chassis frame, FEA analysis has to be done in current methodology. The number of iterations have to be done to build an appropriate model with low weight, which can meet the design requirements. At first, conceptual design mock-up unit is to be developed then FEA (CAE) analysis to be done on it. If any design criteria are not met, then this cycle repeats again until it fulfils the required stiffness. Today, the direct stiffness procedure is the basic principle of almost every FEA software package.

Today’s growing commercial vehicle population creates a demand for fossil fuel surplus requirement and develops highly polluted urban cities in the world. Hence addressing both factors is very much essential. Battery electric vehicles are with limited vehicle range and higher charging time. So it is not suitable for the long-haul application. In further the hydrogen fuel cell-based electric vehicles are the future of the commercial electric vehicle to achieve long-range, zero-emission and alternate for reducing fossil fuels requirement. The hydrogen fuel cell electric vehicle range, it means the total distance covered by the vehicle in a single filling of hydrogen into the onboard cylinders. And here the prediction of the vehicle range is essential based on optimal parameters; vehicle acceleration, speed, trip time etc. before the start of the trip.

Most popular practice for analyzing the Subsystem failures in commercial vehicles is physical testing. These physical tests are carried out by three tests; Endurance testing, Accelerated Endurance Testing and Rig test simulation. All the three methods are costly and repetitive iterations of these tests is not economical. Therefore, in our organization, we established a method in virtual domain in order to reduce the repetitive iterations and also reduction in time consumed per iteration. General practice in our organization for Finite Element Analysis (FEA) calculation was inclusive of Model preparation, Transient analysis using Nastran. The results from the Transient analysis are used for performing fatigue analysis in fatigue software. In this process, Transient analysis and Model preparation are very much time consuming processes. Model preparation cannot be reduced, but to reduce the transient analysis time, we established a method in frequency domain (vibrational fatigue) [1].