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Nowadays automotive cabin comfort has become a necessity rather than an optional feature, with customers demanding more comfort features. Thermal comfort becomes an essential part of this expectation. Since steering wheel is the first surface that the driver will touch once he enters the vehicle, maintaining thermal comfort of steering wheel becomes important, especially in tropical countries like India where a car parked in hot weather can get significantly warm inside. In this work, two design concepts for automotive steering wheel thermal control based on thermoelectric effect are depicted along with a detailed mathematical model. Thermoelectric coolers were selected for this purpose as it is solid state, compact & scalable solution to achieve rapid cooling rates. This was the desired feature expected from an integration standpoint in automotive architecture.

Automotive suspension system forms the basis for the design of vehicle with durability, reliability, dynamics and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The current focus in automotive industry is to reduce the weight of the automotive parts and components without compromising with its static and dynamic mechanical properties. This weight reduction imparts fuel efficiency with added advantages. High-Strength Low Alloy steel (HSLA) offers optimum combination of ductility, monotonic and cyclic mechanical properties. Furthermore, welding processes offer design flexibility to achieve robust and lightweight designs with high strength steels.

The automotive engineering fraternity is facing tremendous challenges to improve fuel economy and emissions of the internal combustion engine. The stringent CAFÉ standards for CO2 emissions are expected to become further demanding as time progresses. Indian OEM engineering experts have been considering various technology options to improve vehicle fuel economy. However, the time and costs associated with the development of these strategies and technologies remains a point of major concern and challenge. The potential of a technology to reduce fuel consumption can be estimated in three basic ways. One approach involves developing an actual prototype engine and vehicle with the technologies under evaluation, performing the actual measurements. Some variability from test to test is although expected, this method is the most accurate but time consuming and very expensive.

State of Charge (SoC) estimation of battery plays a key role in strategizing the power distribution across the vehicle in Battery Management System. In this paper, a model for SoC estimation using Extended Kalman Filter (EKF) is developed in Simulink. This model uses a 2nd order Resistance-Capacitance (2RC) Equivalent Circuit Model (ECM) of Lithium Ferrous Phosphate (LFP) cell to simulate the cell behaviour. This cell model was developed using the Simscape library in Simulink. The parameter identification experiments were performed on a new and a used LFP cell respectively, to identify two sets of parameters of ECM. The cell model parameters were identified for the range of 0% to 100% SoC at a constant temperature and it was observed that they vary as a function of SoC. Hence, variable resistance and capacitance blocks are used in the cell model so that the cell parameters can vary as a function of SoC.

Reduction in the drivetrain losses of a vehicle is one of the important contributing factors to amplify the fuel economy of vehicle, particularly in heavy commercial vehicle. The conversion of 6 × 4 drive vehicle into 6 × 2 drive has a benefit of improving the fuel economy of a vehicle by reducing the drivetrain losses occurring in the second rear axle. It was cultured by calculation that in 6 × 2 drive the tractive force available at the wheels, of heavy commercial vehicle with GVW of 44 tons and above, will be much higher than the frictional force transmission capacity of tires, when the engine is producing peak torque on the driving duty cycle like going on steep gradient road. In such situations the tires will start to slip and may result in deteriorating the fuel economy and excessive tire wear. On the other side the flat road driving duty cycle in 6 × 2 drive will give better fuel economy than 6 × 4 drive.

Traditionally the bushes used for automotive suspension are tested by methods which either don't address the environmental conditions including dust or mud, which convert a 2-body wear condition to 3-body wear condition prevailing in the field or not representative of the complete load bearing area of the bushes coming in contact with the pin. To address the above issues, a novel method of testing has been designed to take care of the loading type, environmental conditions and load bearing area of the bushes to simulate the field conditions.

A 4t off-road military application vehicle was offered to the customers for assessment. During the evaluation adverse feedback of 1) harsh ride in off-road terrain, particularly during hump-crossing and 2) issues during high mobility were reported. Vehicle configuration was front and rear rigid axle suspension with leaf spring anti-roll bar, 4×4 and all terrain tyres. Vehicle application was “on-road” [GS (General-services)], as well as “off-road” (Reconnaissance purpose). The feedback was critically analyzed on the vehicle with the simulation of field conditions. Since the vehicle was still under customer evaluation, solution for the feedback required was quick and within boundary condition (maximum possible allowable limits of modification) of no major change in the suspension design as it was affects homologation cycle. Present paper describes the detailed analysis of the influence of each parameter on system.

Electrical and Series Hybrid Vehicles are generally provided with single speed reduction gearbox. To improve performance and drive range, a two-speed gearbox with coordinated control of traction motor and gearshift actuator is proposed. For a two-speed gearbox, gearshift without clutch would increase the shifting effort. Active Synchronization is introduced for a smoother gearshift even without clutch. The quality of gearshift is considered as a function of applied shift force and time taken. To enhance the quality of the gearshift further, the location of the synchronizer in the transmission system is optimized. To validate the improvement in the quality of the gearshift, a mathematical model of the two-speed gearbox incorporating proposed location of synchronizer assembly along with active synchronization is developed. The qualitative and quantitative analysis of the results achieved is presented.

Comfortable cabin environment from temperature, noise and vibration point of view is one of the most desirable aspects of any vehicle operating in hot or cold environment. Noise generated from HVAC system is one of the most irritating phenomena resulting in customer dissatisfaction and complaints. It becomes absolutely necessary to have low HVAC noise levels when the target market has hot weather all round the year. Balance between control of temperature in desired way with least possible noise and vibration is the key for HVAC performance optimization within constrains posed by design and cost. This paper describes the approach for NVH refinement of front HVAC system proposed for a vehicle with limited off-road capability for which packaging constraints and late changes related to airflow and HVAC unit design for meeting comfort and crash requirements resulted in deterioration of noise and vibrations while operation.

In this paper, design methodology of antiroll bar bush is discussed. Typical antiroll bar bushes have slide or slip mechanism, to facilitate the relative motion between ARB and bush. Inherently, this relative motion causes wear and noise of bush. To eliminate stated failure modes, the next generation bushes have been developed, which are using torsion properties instead of slip function. These bushes are already being used in various vehicles. This paper focuses on developing the simple mathematical model, design approach and optimization of ARB bushes. Also, comparison study is presented exploring, the differences and design criteria's between conventional and new generation anti-roll bar bushes.

In hydraulic power assisted steering (HPAS) system higher steering oil temperature can cause deterioration of oil reservoir, thermal failure of pump/valves and can diminish system performance. Thermal analysis is performed for HPAS system architecture development in order to maintain steering oil temperature within design limits for optimal performance & increased life of HPAS steering system. In present study mathematical model of HPAS system consisting of steering pump, flow and pressure control mechanism, rotary valve, steering circuit pipes and hoses, thermal interaction with ambient is developed. The model is able to predict steering torque-hydraulic pressure dynamics of HPAS system as per design. Developed HPAS system model is integrated with steering kinematic and uniquely developed tire-road contact patch sliding model for estimating non-linear rack force behavior at higher steering angle.