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Accident statistics shows pedestrian accident fatalities as one of the important concerns globally. In view of this, new test protocols for pedestrian safety have been drafted in regulation as well as in consumer group. Also as per new ENCAP requirements, pedestrian safety assessment is used as one of the four assessment criteria's (Adult protection, child safety, pedestrian safety, safety assist) in deciding the overall vehicle safety. Hence today importance of pedestrian safety is perceived as never before in vehicle development program. Basically pedestrian safety evaluation involves subsystem level (head form, upper leg form and lower leg form) impact tests representing human body parts, at specific region on test vehicle with injury limits to decide the severity of impact. In general these injuries are governed by vehicle styling, vehicle stiffness, hard points clearances from vehicle exterior like bonnet, bumper etc.

Passenger cars in the top segment have seen fast growth over the last few decades with an increasing focus on luxury, convenience, safety and the quality of driver experience. The headliner is a decorative and functional trim system covering the underside of the roof panel. It enhances the aesthetics and elegance of the car interiors. In premium vehicles, the headliner system has to suffice interior quietness and integrity apart from the performance and regulatory requirements. The Design Validation Plan requirements cover its contribution to the vehicle interior noise control, occupant safety, and perception of build quality. Contributions can be very significant and primarily be determined by design and material parameters. Also, headliner interactions with an adjacent body in white structure are crucial from performance point of view. Various foam options are available with different functions such as structural, acoustic, and energy-absorption.

Battery Thermal management is a major challenge for occupant safety in an electric vehicle. Predicting the battery electrical losses and thermal behaviour is another challenge for the battery management system. Different virtual models are developed for cell level and pack level thermal evaluation. All these models have a varying degree of accuracy and limitation. The latest developed model is more accurate and can predict the battery cell & pack level temperatures. The battery can be modeled in different ways, ECM (Electrochemical model), EIS (Electrochemical Impedance Spectroscopy) [1]. Newman model is a well-known electrochemical model. [2]. EIS uses a combination of DC and small AC signal [3,4]. ECM model also used for estimating SOC and in BMS [5]. The cell temperature in the battery pack not only depends upon the cell inside physics but also depends upon cell outside cooling physics. Cell outside physics is simulated by 3D CFD software during the design process [6].

The unit analysis methodology can be used for designing component or product in a product development process. This method may be used for designing the crush can, bumper beam, crush can long member, B-frame or A-pillar in frontal impact analysis. Unit assembly model technique can be effectively used in many CAE load cases to evaluate CAE simulations such as pedestrian impact analysis (ECE R78 / ENCAP), interior trim related head impact simulations (FMVSS201U), under run protection simulation for commercial vehicles (Front Underrun Protection Device ECE R93, Rear Underrun Protection Device ECE R58, Side Underrun Protection Device ECE R73), airbag deployment optimization etc. These CAE analyses correlate better with actual test. This paper gives idea about how the cost of product design can be reduced by using unit analysis. To reduce time of vehicle development such as cost of prototype, testing cost, optimization cost unit analysis is more economical.

Frontal collisions account for majority of car accidents. Various measures have been taken by the automotive OEMs’ with regards to passive safety. Honeycomb meso-structural inserts in the front bumper have been suggested to enhance the energy absorption of the front structure which is favorable for passive safety. This paper presents the changes in energy absorption capacity of hexagonal honeycomb structures with varying cellular geometries; under frontal impact simulations. Honeycomb cellular metamaterial structure offers many distinct advantages over homogenous materials since their effective material properties depend on both, their constituent material properties and their cell geometric configurations. The effective static mechanical properties such as; the modulus of elasticity, modulus of rigidity and Poisson’s ratio of the honeycomb cellular meso-structures are controlled by variations in their cellular geometry.

Restraints systems (airbags and seat belts) have been proven to be very effective in occupant protection in crashes. Timely deployment of these devices is very essential for meeting performance requirements. Precision and reliability in restraints deployments demand selection of a robust sensing configuration that caters to the wide variations of real world. This paper highlights complexities involved in engineering of restraints sensing configurations through different case studies on vehicle programs. The paper explains the need for restraints sensing configuration optimization and well defined sensing strategies for a robust solution in real world. A methodology is discussed to achieve good discrimination between crashes of different types and severities. Virtual and physical test data collected at different stages of vehicle development is used. It is found that criteria for threshold levels in restraints sensing requires efforts to identify real world usage variations.

Integrating safety features may lead to changes in vehicle interior component designs. Considering this complexity, design guidelines have to take care of aspects which may help in package feasibility studies that consider systems performance requirements. Occupant restraints systems for protection in side crashes generally comprise of Side Airbag (SAB) and Curtain Airbag (IC). These components have to be integrated considering design and styling aspects of interior trims, seat contours and body structure for performance efficient package definition. In side crashes, occupant injury risk increases due to hard contact with intruding structure. This risk could be minimized by cushioning the occupant contact through provision of SAB and Inflatable IC. This paper explains the methodology for deciding the package definitions using Knowlwdge Based Engineering (KBE) tools.

Pedestrian impact test procedures allow tolerances on test conditions of impact such as mass of the impactor, impactor position, impact speed etc. The variation in these parameters affects the injury measurements in a test. This paper focuses on sensitivity study of variations in these parameters, within specified tolerances, on head form impact and lower leg impact injury measurements. The aim of this sensitivity study is to find out the most influencing test parameter for the injuries. The exercise was carried out using Computer Aided Engineering (CAE) simulations.

The performance of door assembly is very significant for the vehicle design and door sag/set is one of the important attribute for design of door assembly. This paper provides an overview of conventional approach for door sag/set study based on door-hinge-BIW assembly (system level approach) and its limitation over new approach based on subassembly (subsystem level approach). The door sag/set simulation at system level is the most common approach adopted across auto industry. This approach evaluates only structural adequacy of door assembly system for sag load. To find key contributor for door sagging is always been time consuming task with conventional approach thus there is a delay in providing design enablers to meet the design target. New approach of door sag/set at “subsystem level” evaluates the structural stiffness contribution of individual subsystem. It support for setting up the target at subsystem level, which integrate and regulate the system level performance.

Micro Hybrid Systems are a premier approach for improving fuel efficiency and reducing emissions, by improving the efficiency of electrical energy generation, storage, distribution and consumption, yet with lower costs associated with development and implementation. However, significant efforts are required while implementing micro hybrid systems, arising out of components like Intelligent Battery Sensor (IBS). IBS provides battery measurements and battery status, and in addition mission critical diagnostic data on a communication line to micro hybrid controller. However, this set of data from IBS is not available instantly after its initialization, as it enters into a lengthy learning phase, where it learns the battery parameters, before it gives the required data on the communication line. This learning period spans from 3 to 8 hours, until the IBS is fully functional and is capable of supporting the system functionalities.

Engine Stop/Start System (ESS) promises to reduce greenhouse emissions and improve fuel economy of vehicles. Previous work of the Authors was concentrated on bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, actual benefits of ESS are reduced. A modified control algorithm was proposed and proven for the local driving conditions in India. The ways in which a given driver behaves on the controls of the vehicles like Clutch and Brake Pedals, Gear Shift Lever were not uniform across the demography of study and varied significantly.

Authors were challenged with a task of developing a full vehicle simulation model, with a target to simulate the electrical system performance and perform digital tests like Battery Charge Balance, in addition to the fuel efficiency estimation. A vehicle is a complicated problem or domain to model, due to the complexities of subsystems. Even more difficult task is to have a control algorithm which controls the vehicle model with the required control signals to follow the test specification. Particularly, simulating the control of a vehicle with a manual transmission is complicated due to many associated control signals (Throttle, Brake and Clutch) and interruptions like gear changes. In this paper, the development of a full vehicle model aimed at the assessment of electrical system performance of the vehicle is discussed in brief.

The vehicle crash signature (here on referred as crash pulse) significantly affects occupant restraints system performance in frontal crash events. Restraints system optimization is usually undertaken in later phase of product development. This leads to sub-optimal configurations and performance, as no opportunity exists to tune vehicle structure and occupant package layouts. In concept phase of development, crash pulse characterization helps to map occupant package environment with available structure crush space and stiffness. The crash pulse slope, peaks, average values at discrete time intervals, can be tuned considering library of restraints parameters. This would help to derive an optimal occupant kinematics and occupant-restraints interaction in crash event. A case study has been explained in this paper to highlight the methodology.

Curtain airbag design offers protection in side crash and it plays a critical role in safety of the vehicle. Curtain airbag provides protection to the occupant in many impact events like frontal offset, side barrier, and side pole and rollover condition. For a vehicle to be safe for any side impact condition, the curtain airbag should deploy and take its final shape before any injury happens to the occupant. During deployment, it is important that the airbag chooses a path of minimum resistance and does not get entangled in interior trims. In reality, the trims always do obstruct the path of airbag deployment in some way. Hence, special care has to be taken care for designing areas surrounding curtain like providing hinges, deflector components etc. to avoid being caught. There are about ten different factors on this deployment is dependent upon. This paper discusses these factors and the effect of the factors on the trims and airbag development.

This paper describes the Common Automobile Program (CAP) that can be implemented to improve mass transportation. CAP is the use of automated electric vehicles using smart navigation and control technologies to improve mass transportation. In CAP, common vehicles are used by different passengers, thus, reducing the on-road traffic and also the parking space required. Various low-cost stations are to be built along specified paths and the vehicle can be used at the convenience of the commuter. Currently, buses and trains require the passengers to wait at the station and a significant amount of time is spent at intermediate stops. The vehicle in CAP runs directly from origin to destination and also eliminates the waiting time at stations. Passengers do not wait for vehicles; instead vehicles wait for the passengers. The journey starts as the passenger enters the station and selects the destination.

Computer Aided Engineering (CAE) plays an important role in the product development. Now a days major decisions like concept selection and design sign off are taken based on CAE. All the Original Equipment Manufacturers (OEMs) are putting consistent efforts to improve accuracy of the CAE results. In recent years confidence on CAE prediction has been increased mainly because of good correlation of CAE predictions with the test results. Defining proper correlation criteria and using a systematic approach helps significantly in building the overall confidence level for predictions given by CAE simulations. Representation of manufacturing effects on material properties and material failure in the simulation is still a big challenge for achieving a good CAE correlation. This paper describes side impact test vs CAE correlation. The important parameters affecting the CAE correlation were discussed.