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Prime concern for electric vehicle where the application of the vehicle is public transport, is the charging of vehicle and operation of its infrastructure. Such an example of operating the EV buses is under the GCC (gross cost contract) model, with high operation time and comparatively lesser time for charging. It is challenging to meet these requirements. To counter this situation in fleet operated busses it is proposed to adapt an automated charging method which involves minimum man power intervention and automated mechanism to connect & disconnect the charging connectors. This paper proposes an automated pantograph mechanism based method of charging EV buses, meeting requirements as per SAE J3105 & ISO 15118 standards, which would be an ideal way to resolve the current situation.

Commercial vehicle are exposed to harsh environment conditions like dust, mud, wind, rain, extreme sun and winter throughout. Apart from white goods and other conventional loading these vehicles also used in applications which involve Handling of Dirty Loads, Construction Raw materials, Mining Industry etc. which leads to fast deterioration of Interiors. Also, in most cases drivers are not the owners. Hence due to high cost of Cleaning at dealerships and low Product maintenance awareness amongst Commercial Vehicle Users, on Road Washing & Cleaning by riverside is common practice which leads to early deterioration of Interior trims. This paper deals with the retention of newness of soft trim parts such as headliner, wall trims and carpets. Causes of product deterioration and attributes which influence newness like product appeal, NVH, perceived quality, environmental impact, geometry retention over time etc. have been discussed in detail.

With the revolutionary advancements in modern transportation, offering advanced connectivity, automation, and data-driven decision-making has put the intelligent transportation systems (ITS) to a high risk from being exposed to cyber threats. Development of modern transportation infrastructure, connected vehicle technology and its dependency over the cloud with an aim to enhance safety, efficiency, reliability and sustainability of ITS comes with a lot more opportunities to protect the system from black hats. This paper explores the landscape of cyber threats targeting ITS, focusing on their potential impacts, vulnerabilities, and mitigation strategies. The cyber-attacks in ITS are not just limited to Unauthorized Access, Malware and Ransomware Attacks, Data Breaches, Denial of Service but also to Physical Infrastructure Attacks.

A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers.

The vehicle Heating, Ventilation and Air conditioning (HVAC) system is designed to meet both the safety and thermal comfort requirements of the passengers inside the cabin. The thermal comfort requirement, however, is highly subjective and is usually met objectively by carrying out time dependent mapping of parameters like the velocity and temperature at various in-cabin locations. These target parameters are simulated for the vehicle interior for a case of hot soaking and its subsequent cool-down to test the efficacy of the AC system. Typically, AC performance is judged by air temperature at passenger locations, thermal comfort estimation along with time to reach comfortable condition for human. Simulating long transient vehicle cabin for thermal comfort evaluation is computationally expensive and involves complex cabin material modelling.

The traditional method of collecting the Road Torque Data of a vehicle is by instrumenting and running the vehicle on different road terrains. Every time, physical testing becomes tedious & most challenging task due to unavailability of unit under tests, kind of resource required and so on. However, in view of response to the fast emerging technology & limit less competition, it has become mandatory to develop & launch products in market within no time. In recent times, there is increased demand for physical road torque data measurements for a vehicle program based on its application and different powertrain configurations, which clearly shows that unless we front load the data to design it is practically impossible to meet the deadlines. Each of these measurements cost and consumes valuable resources of the company in collecting and analyzing the data.

During every clutch engagement energy is dissipated in clutch assembly because of relative slippage of clutch disc w.r.t. flywheel and pressure plate. Energy dissipated in clutch is governed by many design parameters like driveline configuration of the vehicle vis-a-vis vehicle mass, and operational parameters like road conditions, traffic conditions. Clutch burning failure, which is the major failure mode of clutch assembly, is governed by energy dissipation phenomenon during clutch engagement. Clutch undergoes different duty cycles during usage in city traffic, highways or hilly regions during its lifetime. A test schedule was derived using energy dissipated during every clutch engagement event as a base and using road load data collected on the vehicle. Road load data was collected in different road mix conditions comprised of city traffic, highway, hilly region, rough road for few hundred kilometers.

In case of design of passenger vehicles, one of the priorities is how the dynamics behavior shall be perceived by the vehicle occupants. One of many such handling parameters is the vehicle body roll, which is usually quantified by the vehicle's Steady State Roll Gradient. This number gives an indication of the rotation of the vehicle body in response to unit lateral force acting on the vehicle, as in the case of cornering. However it does not necessarily indicate the roll as sensed by a person seated inside it. A study showed that the subjective feel is not entirely dependent on roll gradient. In some cases the occupant may feel more confident and comfortable in a vehicle with a relatively higher roll gradient, or vice versa. In such cases, designing for roll gradient alone may not serve the purpose of secure and comfortable feel. To account for this discrepancy, a study was carried out to quantify the motion felt by the occupant.

The objective of the work presented in this paper is to provide an overall CFD evaluation and optimization study of cabin climate control of air-conditioned (AC) city buses. Providing passengers with a comfortable experience is one of the focal point of any bus manufacturer. However, detailed evaluation through testing alone is difficult and not possible during vehicle development. With increasing travel needs and continuous focus on improving passenger experience, CFD supplemented by testing plays an important role in assessing the cabin comfort. The focus of the study is to evaluate the effect of size, shape and number of free-flow and overhead vents on flow distribution inside the cabin. Numerical simulations were carried out using a commercially available CFD code, Fluent®. Realizable k - ε RANS turbulence model was used to model turbulence. Airflow results from numerical simulation were compared with the testing results to evaluate the reliability.

Vehicle incab booming perception, a low frequency response of the structure to the various excitations presents a challenging task for the NVH engineers. The excitation to the structure causing boom can either be power train induced, depending upon the number of cylinders or the road inputs, while transfer paths for the excitation is mainly through the power train mounts or the suspension attachments to the body. The body responds to those input excitations by virtue of the dynamic behavior mainly governed by its modal characteristics. This paper explains in detail an integrated approach, of both experimental and numerical techniques devised to investigate the mechanism for boom noise generation. It is therefore important, to understand the modal behavior of the structure. The modal characteristics from the structural modal test enable to locate the natural frequencies and mode shapes of the body, which are likely to get excited due to the operating excitations.

As the vehicle functions are getting distributed over multiple ECUs in order to realize various complex control functions, the need for sophisticated on-board diagnostic strategies are increasing in automotive domain, leading to a significant amount of hardware and software implementations for fault management inside various ECUs in the vehicle. This paper proposes optimized vehicle level approach for fault management strategies, wherein a centralized intelligent Gateway Module is proposed in the vehicle network architecture, which will be responsible for fault management of the complete vehicle in a chronological sequence. This Gateway Module will thereby have the possibility to group a cluster of faults raised by different ECUs and correlate them meaningfully to guide the operator towards root cause of the fault.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.

In the commercial vehicle business, Tractor-trailer combination vehicles are mostly used for carrying heavy loads for longer distances. To improve operating economy of the vehicle by reducing turn around time, it becomes a necessity to have a better driving comfort level for the vehicles. In a Tractor-trailer combination vehicle, due to point load acting on the tractor, pitching effect on the cab is very dominant. To overcome this pitching effect, a fully suspended cabin (suspended at four points) has been designed in order to have better ride comfort as compared to the fixed cabin. This paper discusses some of the measures taken to reduce the overall cabin pitching effect on Tractor -trailer combination vehicles.

The use of Wheel Force Transducers (WFTs) to acquire data for laboratory simulation is becoming standard industry practice. However, in test rigs where we have only the suspension module and not the complete vehicle, does the reproduction of the orthogonal forces and moments at the wheel centre guarantee an accurate replication of the fatigue damage in the suspension components? The objective of this paper is to review the simulation methodology for a highly non-linear suspension in a 3 DOF (degree-of-freedom) suspension test rig in which the simulation was carried out using only the three orthogonal loads and vertical displacement. The damage at critical locations in the suspension is compared with that on the road and an assessment of the simulation using the WFT is made based on a comparison of the damage on the road vs. the rig.

It is customary to select a twist beam rear suspension for front wheel driven small and medium range passenger cars. Besides better primary / secondary ride comfort, roll stiffness tuning ability, ease of assembly & good packaging solutions than the conventional semi trailing arm/ rigid axle suspensions, twist beam suspension system accentuate the concentration required in placing & orienting the cross beam to achieve certain imperative kinematical characteristics. In order to make the solutions of the required kinematical targets viable, it is vital to have the packaging space and stress concentration within yield limits given the weight & cost targets. This paper presents the work done on twist beam type suspension for a new generation entry level B-Class hatchback vehicle developed. To reduce the time consumed in validation of different design proposals a virtual validation process was developed.