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Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.

Leaf Springs are commonly used as a suspension in heavy commercial vehicles for higher load carrying capacity. The leaf springs connect the vehicle body with road profile through the axle & tire assembly. It provides the relative motion between the vehicle body and road profile to improve the ride & handling performance. The leaf springs are designed to provide linear stiffness and uniform strength characteristics throughout its travel. Leaf springs are generally subjected to dynamic loads which are induced due to different road profiles & driving patterns. Leaf spring design should be robust as any failure in leaf springs will put vehicle safety at risk and cost the vehicle manufacturer their reputation. The design of a leaf spring based on conventional methods predicts the higher stress levels at the leaf spring center clamp location and stress levels gradually reduce from the center to free ends of the leaf spring.

In recent years, the push for reduced product development timelines has been more than ever with significant changes in the automotive market. High electrification, intelligent vehicle systems and increased number for car manufacturers are a few key drivers to the same. The front loading of development activities is now a key focus area for achieving faster product development. From vehicle dynamics point of view availability of subjective evaluation feedback plays a key role in optimization various system specifications. This paper discusses an approach for front loading through parallel development of the tire and vehicle chassis system, using advanced simulation and driving simulator technology. The proposed methodology uses virtual tire models which in combination with real-time vehicle model enables subjective evaluation of vehicle performance in driver-in-loop simulators.

The focus on driver and occupant safety as well as comfort is increasing rapidly while designing commercial vehicles in India. Improvements in the road network have enhanced road transport for commercial vehicles. Apart from the cost of operation and fuel economy, the commercial vehicles must deliver goods within stipulated time. These factors resulted in higher speed of operation for commercial vehicles. The design should not compromise the safety of the vehicle at these higher speeds of operation. The vehicle should obey the driver’s intended direction at all speeds and the response of the vehicle to driver input must be predictable without much larger surprises which can lead to accidents. The commercial vehicles are designed with rigid axle and RCB type steering system. This suspension and steering design combination introduce steering errors when vehicle travel over bump, braked and while cornering.

In farm tractors, the available drawbar power, and Power Take-Off (PTO) power are generally lower than the engine power due to parasitic losses. These losses are caused by engine-driven auxiliary loads such as cooling fans, hydraulic pumps for power steering, alternators, etc. Minimizing these parasitic losses can increase the available drawbar power and PTO power, resulting in direct fuel savings by reducing fuel consumption. The continuous increase in fuel costs and the environmental impact of emitted gases from burned fuel into the atmosphere have necessitated the replacement of hydraulic power steering and mechanical fans with Electric Power Steering (EPS) and electric fans, respectively, to improve efficiency. The existing battery has been replaced with a higher capacity battery to provide power to the electric fan, electric power steering, and other electrical components.

Range anxiety is one of the major factors to be dealt with for increasing penetration of EVs in current Automotive market. The major reasons for range anxiety for customers are sparse charging infrastructure availability, limited range of Electric vehicles and range uncertainty due to diverse real-world usage conditions. The uncertainty in real world range can be reduced by increasing the correlation between the testing condition during vehicle development and real-world customer usage condition. This paper illustrates a more accurate test methodology development to derive the real-world range in electric vehicles with experimental validation and system level analysis. A test matrix is developed considering several variables influencing vehicle range like different routes, drive modes, Regeneration levels, customer drive behavior, time of drive, locations, ambient conditions etc.

Powertrain complexity rapidly increasing to meet fast moving regulation requirements. The BS6 Phase-1 regulation norms were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase-2 of the BS6 regulation norms were came into effect on April 1, 2023. To meet this stringent regulation requirement, need effective performance of after treatment systems like DOC, DPF and SCR demands critical hardware selection and implementation. In Indian market, LCV application is cost sensitive and highly competitive where operational cost is most critical factor. Naturally aspirated engine has less operating cost, which is the best for LCV applications, but is has its own challenges to meet BS6 norms like higher engine out NOx, dynamic temperature profiles etc. A robust DeNOx emissions strategy is developed in naturally aspirated engine LCV application to meet cycle emissions, real drive emissions and OBD requirements.

As a car OEM, we continuously strive to set the bar for competitors with every product. Consumer travel experiences are enhanced by increasing passenger cabin silence. There is only one steering system opening in the firewall panel, which is used for allowing intermediate shaft's fitment on the pinion shaft of the steering gear. The steering grommet is the sole component that covers the firewall cut-out without disrupting steering operations, which has a substantial impact on the NVH performance of the vehicle. It is typically used in cars to eliminate engine noise and dust entering to passenger compartment. The part is assembled inside the vehicle where the steering intermediate shaft passing through BIW firewall panel. We use a bearing, plastic bush, or direct rubber interference design in the steering grommet to accommodate the rotational input the driver provides to turn the automobile.

Restraint systems in automotives are inevitable for the safety of passengers. Seat belts are one such restraint system in automotives that prevent drivers and passengers from being injured during a crash by restraining them back. Seatbelt on automotives has interface with Body-in-white (henceforth called as BIW) and Trim parts in-order to serve its purpose at vehicle level. One such interface part of seat belt is the web guide, which assists and ensures the nylon web’s smooth motion at different seat track positions. Web-guides on automotives ensure the flawless motion of seat belt web at pillar trim areas. In this paper, we are discussing alternate ways of assisting the seat belt web without the web-guide as a separate part. In-order to assist and ensure the motion of nylon web in its trajectory, we have extended the flange of the pillar trim involved.

The increasing demand for higher specific power, fuel economy, Operating Costs as well as meeting global emission norms have become the driving factors of today’s product development in the automotive market. Substitution of high-density materials and more precise adjustment of material parameters help in significant weight decrease, but it is accompanied by undesirable cost increase and manufacturing complexity. This becomes a challenge for every automotive engineer to balance the above parameters to make a highly competitive design. This work is a part of the Design and Development of 2.2 L, 4 Cylinder TCIC Diesel Engine for a whole new vehicle platform, concentrated on automotive passenger car operation. This paper explains the selection of a suitable cylinder head gasket technology for a lightweight engine that acts as a sealing interface between the cylinder block and cylinder head.

This paper focuses on reducing abnormal noise originating from suspension when driving on rough road at the speed of 20 kmph. The test vehicle is a front wheel driven monocoque SUV powered by four cylinder engine. Cabin noise levels are higher between 100 to 800 Hz when driven on rough road at 20 kmph. Vibration levels are measured on front and rear suspension components, front and rear subframe, subframe connections on body to identify the noise source locations. Since the noise levels are dominant only in certain rough patches at very narrow band of time, wavelet analysis is used for identification of frequency at which the problem exist. Based on wavelet analysis, it is identified that the vibration levels are dominant on front lower control arm (LCA). The dynamic stiffness of LCA bushes is reduced by ~ 40% to improve the isolator performance which reduced the noise levels by ~ 9 dB (A) at the problematic frequency band.

In manual transmission, the vital function of synchronizer pack is to synchronize the speed of the target gear for smooth gear shifting. The synchronizer pack consists of various elements and each of these elements has specific function. These elements are baulk rings, shifter sleeve, hub, synchro key, synchro springs etc. The function of synchronizer can be affected due to failure of any one of these elements. This work focuses on the failure of synchronizer pack due to synchro spring failure. The function of synchronizer spring is to exert the required force, to index the synchronizer ring before the movement of shifter sleeve over synchronizer ring. During the shifting of shifter sleeve from one gear to another gear, the springs deflect in both shifting directions. This causes fatigue failure of synchronizer springs. The manufacturing variations, and part quality issues results in very early fatigue failure of synchronizer springs.

Internal combustion engine vehicles are major contributors to many environmental and health hazardous emissions and sometimes consume more fuel. New regulations like Corporate Average Fuel Efficiency (CAFÉ) norms are coming up and demand lower emissions. Original Equipment Manufacturers (OEMs) are committed to bringing various technological advancements in Internal Combustion Engine (ICE)powered vehicles to maximize their efficiency. Hence it is important to reduce the loss and improve the fuel economy. This paper explains a new approach methodology used for reducing the gearbox drag by 5- 10 %. This improvement can significantly contribute to the overall efficiency improvement thus carbon footprints of vehicle getting reduced.

Original Equipment Manufacturers (OEMs) should innovate ways to delight customers by creating affordable products with improved drive experience and occupant comfort. Vehicle refinement is an important initiative that is often take-up by the project teams to ensure that the product meets the customer’s expectations. A few important aspects of vehicle refinement include improving the Noise Vibration Harshness (NVH), ride and handling performance pertaining to the Functional Image (FI) of the product. Optimizing the suspension design variables to meet both ride and handling performance is often challenging as improving the ride will have a deteriorating effect on handling and vice-versa. The present work involves Multi-Objective Design Optimization (MDO) of the suspension system of an automotive Sports Utility Vehicle (SUV) platform considering both ride and handling requirements, simultaneously.

The major area in which the automotive manufacturers are working is to produce high-performance vehicles with lighter weight, higher fuel economy and lower emissions. In this regard, hollow camshafts are widely used in modern diesel and gasoline engines due to their inherent advantages of less rotational inertia, less friction, less weight and better design flexibility. However, the dynamic loads of chain system, valve train and fuel injection pump (if applicable) makes it challenging to design over-head hollow camshafts with the required factor of safety (FOS). In the present work, high-fidelity FE model of a hollow camshaft assembly is simulated to evaluate the structural performance for assembly loads, valve train operating loads, fuel injection pump loads and chain system loads. The investigation is carried out in a high power-density (70 kW/lit) 4-cylinder in-line diesel engine.

The bolted joints in suspension systems are subjected to severe external service loads during vehicle operation. To prevent the loaded joint from loosening and allowing it to retain its potential energy stored during assembly, a holistic design approach is needed. This paper explains the methodology to design and optimize bolted joints for the suspension systems of a modern 7-seater sports utility vehicle.

In order to sustain in automobile industry, fuel economy and robustness are playing vital role in vehicle. Every gram of weight will have an impact on fuel economy, thus burning a hole in consumers pocket and contributing heavily to the carbon footprint. Composite material development plays important role in meeting the stringent self-imposed targets of the automotive manufacturers and light weighting is becoming a prime option for improving Fuel Economy. The main objective of this paper is to optimize the weight of the luggage lid floor and reduce its cost without compromising on the strength by changing the raw material and manufacturing process. This part is in trunk compartment of the vehicle. Main function of this part is to withstand the luggage load under various user loading patterns at varied temperature and while driving on different road conditions.

PVC (polyvinylchloride) synthetic leather or called leatherette is being widely used for automotive interior applications for seat cover, gear boot, gap hider, steering wheel and roof liner due to their leather like feel and texture, flexibility, sewability, affordability, and wide design freedom. However, the leatherette construction such as top coating, backing fabric and fabric weaving pattern plays a critical role in the finished leatherette performance for the specific application. This study provides the influence of different coating material and different backing fabric in squeak behavior of gear boot PVC leatherette. The squeak behavior was studied by stick slip test as per automotive engineering requirements, and the response of these coating and fabric surface was measured in the form of Risk Priority Number (RPN).

The Introduction of Corporate Average Fuel Economy (henceforth will be addressed as CAFE) regulations demand suitable technological upgrades to meet the significant increase in targets of vehicle fleet fuel economy. Engine Downsizing and Friction Reduction measures help in getting one step closer to the target. In a Conventional Oil Pump, the pump discharge flow and pressure are a direct function of operating speed. There is no control over lubricant flow which results in increased power and fuel consumption due to its unnecessary pumping characteristics irrespective of the actual engine demand. This paper discusses the introduction of a variable displacement oil pump (henceforth will be addressed as VDOP) that was adapted to a 1.5-liter 3 Cylinder Diesel Engine. This approach helps the system to reduce parasitic losses as the oil flow is regulated based on the mechanical needs of the engine. The flow is regulated with help of a solenoid valve which receives input from the ECU.

Accurate ride and handling prediction is an important requirement in today's automobile industry. To achieve the same, it is imperative to have a good estimation of damper model. Conventional methods used for modelling complex vehicle components (like bushings and dampers) are often inadequate to represent behaviour over wide frequency ranges and/or different amplitudes. This is difficult in the part of OEMs to model the physics-based model as the damper’s geometry, material and characteristics property is proprietary to part manufacturer. This is also usually difficult to obtain as a typical data acquisition exercise takes lots of time, cost, and effort. This paper aims to address this problem by predicting the damper force accurately at different velocity/ frequency and amplitude of measured data using Artificial Neural Networks (ANN).