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Virtual validation of automobile components poses a huge challenge and needs continuous process improvements. One of such challenge in FE modelling of welds and understanding its behavior with respect to physical behavior. With the ongoing development of BSVI line of products in commercial vehicle industry, the virtual validation needs to be accurate and close to the physical behavior of the components. The learning and challenges faced during the previous development is implemented in the current study for weld simulation and correlation activity. The brackets welded to the power train components is taken as a challenge in the present work. Initially weld model was depicted in the CAD and was analyzed in CAE by providing proper FE connection. This practice had lot of flaws, approximations due to perpendicularity and flatness concerns in the models leading to consuming a lot of time in model preparation.

In an automobile, main function of the steering system is to allow the driver to guide the vehicle on a desired course. Steering system consists of various components & linkages. Using these linkages, the torque from steering wheel is transferred to tyre which results in turning of the vehicle. Over the life of vehicle, these steering components are subjected to various loading conditions. As steering components are safety critical parts in the vehicle, therefore they should not fail while running because it will cause vehicle breakdown. In commercial vehicle segment, vehicle breakdown means delay in freight delivery which results in huge loss to costumer. Therefore, while designing steering components one should consider all the possible loadings condition those are possible. But, it can’t be done through theoretical calculation. Therefore, physical tests have to be carried out to validate design of steering system, which is very costly & time-consuming process.

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.

Air Pollution is a major concern in our country due to which Indian Government has taken a decision to move from BS-IV to BS-VI which is nearly 90% reduction in NOx and 50% in particulate matter along with addition of particulate number regulation for BS-VI in comparison to BS-IV norms in very short span of time. Vehicle manufacturers are also having the challenge to produce low cost and fuel efficient product with BS-VI solution in order to meet tightening emission regulations and increasing needs of lower fuel consumption. Detailed study is done with different approaches to meet BS-VI emission which is elaborately explained in different aspect of engine design and after treatment parameter with its pros and cons. After Treatment selection plays an important role in engine development to meet stringent emission legislations and customer demands. Strategies for BS-VI were described with the advantage and drawbacks for after treatment selection.

At the time of invention of road coaches, the vehicle consisted only of an axle with wheels and a body attached. Smooth roads were built for a better ride comfort however they were not consistent. The road coaches were too bumpy and uncomfortable for the passenger along with the driver who was not able to control the vehicle. That's why the engineers had to shift their attention to the suspension system for a better ride comfort and handling. The technology has advanced with time so as the suspension system. Rubber ended type leaf spring is one of the suspension system types available in the industry. The main function of a suspension in order of importance is as below: 1 Acts as a cushioning device ensuring the comfort of the driver and passengers; 2 Maximizes the contact between the tires and the road surface to provide steering stability with good handling; 3 Protects the vehicle itself and any cargo or luggage from damage and wear.

Many methods have been developed to evaluate the fatigue life of structures when the joints are as per ideal case. But if the joints are loosening, it leads to increase in loading on the other members which causes failures. Most commonly in commercial vehicle segment welding joint & bolting joints are most popular ones. It is very easy to find out bolts strength & loosening effect in static conditions. But when vehicle is moving (i.e. dynamic condition), same method cannot be used. For this we have developed methodology to predict the bolts loosening in dynamic condition using vibration data. Similarly, loading may differ on the structural members if the welds are failing in dynamic conditions. To overcome this problem, in our organization we have a solution. Of course to simulate welding failures fatigue analysis is mandatory. We are using notch-stress approach for evaluating the welding strength of the joint.

During the last few decades, concerns have grown on the negative effects that diesel particulate matter has on health. Because of this, particulate emissions were subjected to restrictions and various emission-reduction technologies were developed. It is ironic that some of these technologies led to reductions in the legislated total particulate mass while neglecting the number of particles. Focusing on the mass is not necessarily correct, because it might well be that not the mass but the number of particles and the characteristics of them (size, composition) have a higher impact on health. During the diesel engine combustion process, soot particles are produced which is very harmful for the atmosphere. Particulate matter is composed of much organic and inorganic composition which was analyzed after the optimization of SCR and EGR engine out.

A propeller shaft is a mechanical component of drive train that connects transmission to drive wheels/axle with the goal to transfer rotation and torque. It is used when the direct connection between transmission and drive axle is not possible due to large distance between their respective assigned design spaces. In commercial vehicles especially in heavy duty (GVW/GCW>15 tons) a single piece propeller shaft is seldom used due to its inherent disadvantages and therefore, most if not all, of the setups consists of multiple pieces of propeller shaft which are directly mounted on to frame cross members with the help of mounting brackets. As such the mounting bracket assembly undergoes various dynamic and static loading conditions and should be able to withstand these loads. This paper will focus on the FEA analysis of propeller shaft mounting assembly system. Furthermore, these results will be correlated with physical tests results collected from test rig and physical vehicle testing.

In response to Federal Motor Vehicle Safety Standard 108, Side Marker lamps were equipped in both passenger and commercial vehicles. Side marker lights are designed to provide clear visibility and vehicle identification from side way to other drivers/passersby vehicles traveling in perpendicular directions. But in case of harness failure/any malfunctioning/improper maintenance post damages etc., the side marker lamp does not illuminate when it is critically required. This causes serious accidents or loss of human beings as well. Convention side markers are powered by vehicle battery; a solar side-marker operates independently using a photometric switch that activates the light at sunset using stored solar energy. This device mainly works on natural light intensity when it lowers than specific value, the solar energy stored inside device will automatically ignite the side markers, irrespective of manual human intervention to switch it on.

This paper presents theoretical calculation, analysis and simulation (validation and verification) of driveshaft torsion vibration. The vibration measurement validation verification has been carried out on vehicle (4x2) having four cylinder engine 85kw@2800 rpm and six speed manual transmission for getting correlation between values of theoretical calculations and CAE results. This analysis has been done in order to achieve vehicle good performance in terms of driving comfort as well as smooth functionality with zero vibration frequency at high speed. The propeller shaft series selection and refinement has been done using theoretical iteration with operating angle of prop shaft which exits in between the universal joint planes. A frequency of vibration analysis has evaluated at different propeller shaft layout and duty cycle. The vibration performance predictions for vehicles with these design is rigorously done.

The ever-increasing amalgamation of electronics with the automotive industry in the past decade has seen an integration of various sensors like temperature sensors, RPM sensors, wheel speed sensors, etc. on a vehicle. These sensors have enabled a deep insight into vehicle behavior and a good perception of the operating conditions of the vehicle. The accelerometer is one such sensor, the advancement in the semiconductor industry has bred accelerometer sensors in a MEMs form, which is very cost-effective and also facilitates easy integration because of the microform factor. Moreover, As dictated by AIS 140 norms the Telematics ECUs must have a Triaxial accelerometer & Triaxial Gyro sensor integrated inside them.

In order to stand apart from the competition, there is an ever growing demand in Indian commercial vehicle segments to reach higher fuel economy while achieving the emission goals set by the BS-VI norms. With emissions standard set by BS-VI, novel techniques to improve fuel efficiency have to be considered that have least impact with respect to NOx and soot emissions. The optimization of exhaust and intake valve lifts with respect to engine speed, technology commonly known as Variable Valve Lift and Timing (VVT/VVL), has been implemented in many passenger vehicles propelled by gasoline engine. The aim of this work is do initial assessment of utilizing the VVL method on a LMD commercial vehicle diesel engine. A 3.8 litre BS-VI turbocharged EGR engine is used for this study. Valve lift and timing optimization for better fuel efficiency at rated power engine speed is carried out by using one-dimensional thermodynamic simulation software AVL BOOST.

Demand for electrically driven vehicles has increased significantly in recent years, due to its subsidized rate, economical operation and environmentally friendly features. If discussed about India, the sales have increased by 174% in a single year. This drastic jump in sales has encouraged the current automobile manufacturers to come up with more and more electric-driven vehicle platforms in a crunch time frame. And to fulfill these requirements, manufacturers have to work a lot to introduce new technologies like E-axle, which can be space effective, less expensive and easy to assemble. But the introduction of such new technologies brings an even bigger requirement for new validation methodologies, and in the case of electric vehicles (EV) where the development time has been very less, as brought a bigger challenge of more dependency on virtual simulation.

As the commercial vehicle engine heads towards the next generation of stringent emissions and fuel economy targets, all aspects of the internal combustion engine are subject to close scrutiny. Inherently, ICE’s are very inefficient, with efficiency varying between 18 ~ 40%. This efficiency is a function of friction losses, pumping losses and wasted heat. Currently, automotive OEM’s globally are hard at work trying to attack these issues with various solutions to achieve incremental gains. The leading trend is getting more power from less space, also known as downsizing. Due to the importance of downsizing, direct injection and other technologies, it is imperative to highlight another key area, where OEM’s are expanding their limits to gain those extra few kilometers per liter of fuel i.e. weight reduction. From an emissions perspective, it is estimated that every 50 kg of weight reduced from an average 1,500 kg vehicle cuts CO2 emissions by 4 ~ 5 grams.

Downsizing and Light weighting is the latest trend in the automotive industry to achieve more fuel efficient, compact and cost effective design of vehicles. Powertrain components compromise of more than 45% of the total vehicle weight. Automakers are putting significant efforts to reduce the weight of power train components. Integrated design of aluminum Engine Head and Intake manifold has been successfully implemented. Now currently we have identified the gear box housings for downsizing in light duty trucks i.e. Existing light duty trucks Cast Iron transmission. This design has been successfully modified with integrated clutch housing and transmission housing, using lightweight aluminum as the new material, using simulation tools. This lead to weight savings of up to 30% and cost savings of 20-25% as compared to existing cast iron designs. Using an integrated design reduces the assembly cost, makes the design more compact and gives better weight balance.

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.

With the improvement of standard of living, air conditioning has widely been applied in buses. However, in air conditioning buses air distribution is still needs to be improved, One of the main reasons for this sub-quality comfort is two air flow louvers arrangement for 3x2 layout air conditioner buses. Air conditioning buses hatrack louvers are an integral part in providing comfort to passengers. General trend of the numbers of louvers provided to passengers is two louvers for three seats. Disadvantage of having conventional two louvers is that, there is always one passenger left with no option of directing air towards that person. This lead to an opportunity to design three louvers type hatrack instated of conventional two louvers hatrack, for 3x2 seating layout of buses. This way all three passengers can control the louvers for their own comfort and mass of air flow is sufficient for third passenger as well.

The new idea discussed in this paper pertains to the carrier mechanism for spare wheels in heavy commercial vehicles. Typically, these vehicles are equipped with a spare wheel carrier featuring a rope mechanism for loading and unloading the spare wheel. The conventional placement of this system is on the side of the frame/chassis or within the limits of the side member. However, the tire-changing process in this system is often arduous, time-consuming, and requires significant effort. The proposed invention addresses these challenges by repositioning the spare wheel to a vertical orientation, facilitating easier access to its bolts and simplifying the removal process from the mountings. Furthermore, the innovation incorporates a three-way actuation system (Air Actuated, Electric motor-driven, or Hydraulic cylinder actuated mechanisms), thereby reducing the need for manual effort and enhancing driver comfort.

The safety of the heavy duty commercial vehicle (HCV) occupants in an accident is an imperative task and should be considered during the design and development of cabins. The sufficient cabin survival space must be remained after the accident. The main aim of this study is to develop a Finite Element (FE) model of HCV cabin and validate to the test as per AIS029. The present study also includes the assessment of the energy absorption capabilities of the HCV cab during the pendulum impact test. Initially a detailed 3D FE model of a fully suspended HCV cabin was developed and then pendulum impact test simulation was carried out using LS-Dyna explicit solver. Simulation results were compared with the test results and were found in a great agreement in terms of survival space and overall deformation behavior. The load transfer path was described at the time of pendulum impact. The largest amount of impact energy was absorbed by the frontal region of the cabin.

Highway transportation using truck is an important transport mode of goods and product to their destination. Commercial vehicle is expensive mode of transportation so it will be protected from failure. For Heavy duty truck they are fully loaded at one side of transportation and other side empty transportation. In such case lift axle grounded when truck is loaded and when truck is empty it is in lift condition. Lift axle is play important role while loading so it is important that it should not fail. Many times lift axle fails at weld location due several load come on the axle. In this paper study of weld failure to vertical, braking and lateral load come on lift axle when truck is in loading condition. Weld failure check in CAE analysis with various load cases and compare with actual physical vehicle failure. Weld failure correlation well correlate when actual loading are consider in analysis. For analysis loading data is measure from RLDA data that will be used for analysis.