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The commercial vehicle sector (especially trucks) has major role in economic growth of a nation. With improving infrastructure, increasing number of commercial vehicles and growing amount of Vulnerable Road Users (VRUs) on roads, accidents are also increasing. As per RASSI (Road Accident Sampling System India) FY2016-21 database, commercial vehicles are involved in 43% of total accidents on Indian roads. One of the major causes of these accidents is Driver Drowsiness and Inattention (DDI) (approx. 10% contribution in total accidents). This paper describes novel driver-in-loop performance assessment methodology for comprehensive verification of Driver Monitoring System (DMS) for commercial vehicle application. Novelty lies in specification of test subjects, driving styles and variety of road traffic scenarios for verification of DMS system. Test setup is made modular to cater to different platform environments (Heavy, Intermediate, Light) with minor modifications.

Pedestrians are a vulnerable road user group, comprising 22% of global road traffic deaths [1]. In Japan, pedestrian fatalities accounted for 28% of total road fatalities and approximately 16% in Australia. These figures compare with 13% for the USA and 40-50% for India and Thailand [2]. Various pedestrian safety requirements are mandated in different markets in recent years worldwide. For pedestrian head-form, vehicle front-end styling and the free package space below bonnet plays a vital role in deciding the pedestrian head-form safety performance. Currently during initial phase of vehicle development, the free package space requirement is decided based on benchmark data. However, the benchmarking data does not give any insight into the physics involved and is subjective in nature as it varies from vehicle to vehicle. This paper gives an analytical approach for defining the free package space requirements for meeting the targeted pedestrian head form performance requirements.

The interior components of a passenger vehicle are designed to provide comfort and safety to its occupants. In the event of accident, vehicle interiors are primary source of injuries when occupants interact with them. Vehicle interiors consists of Instrument panel (IP), center console, seats and controls in front of seating position etc. Severity of the injuries depends on the energy dissipating characteristics, profiles, projections of different interior components. These are assessed by ECE R21 and IS12553 head form impact tests. To evaluate the Head form impact performance on Interior components, Computer Aided Engineering (CAE) simulations are extensively used during the vehicle development. In order to predict failure of plastic components and snap joints which might lead to expose sharp edges, it is critical to model plastic material and snap joint.

Vehicle crashworthiness is an important aspect of vehicle development. Vehicle structural performance plays a critical role during crash for controlling the occupant injuries. During a crash event, vehicle energy management governs the structural performance and passenger compartment integrity. However, these parameters are dependent on material properties such as yield/ultimate tensile strength, work hardening effects, strain rate dependency, material elongations and material fracture strains. Appropriate representation of these material properties in CAE (Computer Aided Engineering) environment is very critical for reliable prediction of vehicle structural performance during development phase. Among all material properties, material fracture strain is the most complex one and needs detailed material characterization approach for failure definitions.

Apart from being an active safety system the brake system represents an important aspect of the vehicle dynamics. The vehicle retardation and stopping distance completely depend upon the performance of brake system and the functionality of all components. However, the performance prediction of the entire system is a challenging task especially for a complex configuration such as multi-axial vehicle applications. Furthermore, due to its complexity most often the performance prediction by some methods is limited to static condition. Hence, it is very important to have equivalent mathematical models to predict all performance parameters for a given configuration in all different conditions This paper presents the adopted system modelling approach to model all the elements of the pneumatic brake system such as dual brake valve, relay valve, quick release valve, front and rear brake actuators, foundation brake etc.

The engine compartment of passenger car application contains various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the body temperature of individual component. The rise in body temperature of critical components can endanger the durability or functionality of the specific component or a system in which it operates. The aim of this paper is to strategize thermal protection of the rear mounted engine and its components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECUs, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan.

In present day passenger cars, Mobile Air Conditioning (MAC) system is one of the essential features due to rise in overall ambient temperatures and comfort expectation of customers. During the development of MAC system, the focus is on cooling capacity of system for maintaining in-cabin temperatures. However, parameters like solar radiation, air velocities at occupant, relative humidity, metabolic rate and clothing of occupants also influence occupant’s thermal comfort and normally not considered in design of the MAC system. Subjective method is used to evaluate thermal comfort inside vehicle cabin which depends mainly on human psychology. To better understand the effect and minimize the human psychological factors a large sample of people are required. That process of evaluating the comfort inside the vehicle cabin is not only time consuming but also impractical.

Vehicle Ergonomics is one of the most vital factor to be considered in vehicle design and development, as the customer wants a comfortable and performance oriented vehicle. An uncomfortable driving posture can lead to painful driving experiences for longer hauls. The control pedals viz. Accelerator, Brake and clutch pedal (ABC Pedals), are the most frequently used parts in the vehicle, their proper positioning with respect to human anthropology is of prime importance, from driver comfort viewpoint. The methodology currently used for optimizing ergonomics with respect to the positioning of pedals in a vehicle included; measuring anthropometric angles manually with the help of H-Point Machine, subjective jury analysis and through software like RAMSIS, JACK, etc. Manual measurement doesn’t give the flexibility of iterations for optimization. The subjective analysis is based on insinuations thereby, cannot be standardized.