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Brake system development and testing is spread over vehicle manufacturers, system and component suppliers. Test equipment from different sources, even resulting from different technology generations, different data analysis and report tools - comprising different and sometimes undocumented algorithms - lead to a difficult exchange and analysis of test results and, at the same time, contributes to unwanted test variability. Other studies regarding the test variability brought up that only a unified and unambiguous data format will allow a meaningful and comparative evaluation of these data and only standardization will reveal the actual reasons of test variability. The text at hand illustrates that a substantial part of test variability is caused by a misinterpretation of data and/or by the application of different algorithms.

Reliability has been a complicated domain of vehicle engineering, basically due to the quantum of the authentic data required, and variability of parameters that make real contributions to the subject. Reliability of a vehicle in very generic terms, is not only its functional worthiness and consistency, but also its probability to perform satisfactorily within the intended design life for a particular production batch, application domain, operation duty and customer use. Commercial vehicle industry is driven by returns that a vehicle gives, on the investments made, which depend on parameters like minimum turnaround time, lesser breakdowns, optimized maintenance interval and cost of operation etc. Severe operating conditions, regular customer abuse and higher expectations from products (as expected by Indian customer-base) demand a need to deliver more robust and reliable products.

Unprecedented rates of change in the economic equations of air transport infrastructure are impacting military, NASA and civilian fleets. Military aero-asset operational lifespans are being continually assessed for extension, and younger assets are tasked to higher levels of mission dispatch reliability. NASA, post Columbia will now undergo a new round of safety and reliability assessments of structures and wiring on the space shuttle fleet to ensure a safe return to flight. New FAA regulations to improve aging airplane structural and wiring safety motivate comprehensive change in the approach to aviation maintenance. There are concerns that these challenges of improved reliability and life extension will further strain the resources of DOD/NASA and economic health of the civilian aviation industry.

Under the sponsorship of the Coordinating Research Council (CRC), the University of Minnesota (UMN) formed an international research team to investigate the physical and chemical nature of diesel emissions from heavy-duty vehicles while operating on highways (CRC Project E-43). These ambient measurements of vehicle emissions following their release into and dilution by the atmosphere guided the development of dilution and sampling procedures for laboratory test cells to simulate on-highway conditions. The importance, visibility, and potential implications of the project prompted the adoption of a quality assurance (QA) plan by an independent implementation team. Because exhaust aerosol characterization for mobile sources lacks prescribed sampling methodologies, standard operating procedures were developed as part of the QA effort to ensure the consistency and validity of the data collected.

One main general goal during product development in the passenger car industry as well as in the commercial vehicle industry is to reduce time to market. The customer wants to get the newest product and is not accepting the risk of any product call backs. This means the minimization of the risk of field claims for the manufacturer. The challenge to reach this goal is a capable volume production of each new product. To create a competitive, innovative product it is the task for design and simulation engineers in the development phase to design the product in view of function, efficiency, fatigue strength, optimized weight and optimized product costs. Additionally an agreement between design and industrial production planning is required. An early involvement of production engineers into the development of a product ensures design for manufacturing from the very beginning.

High efficiency, power concentration and reliability are the main requirements from Diesel Engines that are used in most technical applications. This becomes more important with the increase of engine size. For this reason the aforementioned characteristics are of significant priority for both marine and power generation applications. To guarantee efficient engine operation and maximum power output, both research and commercial communities are increasingly interested in methods used for supervision, fault-detection and fault diagnosis of large scale Diesel Engines. Most of these methods make use of the measured cylinder pressure to estimate various critical operating parameters such as, brake power, fuel consumption, compression status, etc. The results obtained from the application of any diagnostic technique, used to assess the current engine operating condition and identify the real cause of the malfunction or fault, depend strongly on the quality of these data.

A new simulation-based method for design of powerplant mounting systems is presented. Unlike traditional methods, in which the objective is to obtain a set of powerplant rigid body modes found from experience to be favorable, this new method directly seeks minimal response in the vehicle passenger compartment, regardless of what powerplant modes are obtained. Therefore, the simulation objective exactly matches the design objective: minimal response. The new method, which uses optimization based on response sensitivities, has been implemented into software. Results show that the final response levels are significantly reduced from the baseline, and that typically the final mounting configuration is much different, and better, than the mounting system that would have resulted from application of the traditional method. POWERPLANT MOUNTING is one of the fundamental design characteristics of a motor vehicle.

A major challenge of a System Engineering approach lies in its ability to promote an efficient Process/Method/Tools environment that leads to an efficient and accurate System Referential Repository. The key factor is the definition of a centralized system referential repository that is shared by the various stakeholders involved in the success of industrial projects, including customers, system architects, hardware and software development suppliers, validation and safety teams. This paper describes the development of a use case modeled with the most appropriate tool-chain that fulfills the above System Engineering expectations. Based on standard documents (INCOSE Handbook, ARP4754) and on experience achieved by the development of many System Engineering projects, a methodological approach is defined.

From time to time vehicles need to have their software modules updated for various reasons, such as the introduction of new features in vehicles, the need for changing the navigation map, the need for fine tuning various features of the vehicles, and many others. The software in a vehicle's electronic control unit (ECU) can be updated either at a service station or remotely via wireless links. Remote software update has many advantages: it can save consumers valuable time by not requiring them to bring their vehicles to service stations; software in multiple vehicles can be updated in parallel to save auto companies time and money; software in all recall vehicles can be updated in a timely manner, and so on. There are two main issues related to the remote software update operation. One issue is the bandwidth required for the update operation, and the other issue is the security of the communication links. In another paper we addressed the security issue of the communication links.

The methods used at the British Road Research Laboratory to collect data relating to the injuries sustained by vehicle occupants in road accidents are described. Vehicles of differing interior structural design give rise to different patterns of injury to their occupants, the probable mechanisms producing these injuries have been deduced from the detailed examination of the damage to the car interior caused by the impact of the occupant during the accident. The damage observed in cars involved in accidents and associated with particular injuries was reproduced on undamaged cars of the same make and model, using a suitable dynamic impact method, to give an indirect assessment of the forces causing the injuries.

Definite knowledge as to the behavior of gases and liquids in the manifold of an internal-combustion engine being lacking, an attempt is made to answer the questions: (a) How bad is the distribution, (b) how do the different types of manifold compare, (c) why is the liquid distribution in some manifolds poor and (d) how shall we proceed to correct the trouble? The solution of the problem is affected by the facts that, in extremely cold weather, nearly all fuel is delivered to the engine, at the time of starting, as a liquid; that all cars perform poorly under such conditions, some engines, when cold, “hitting” on only one or two cylinders; and that, because of inferior distribution, many multi-cylinder engines are outperformed by single-cylinder engines of similar design.

Shuttle Transoceanic Abort Landing (TAL) sites, located on the African coast and in Spain, require an emergency medical capability for astronauts who may be injured in an abort landing. The remote African TAL sites present unusual medical planning and logistical problems. Two broad options to meet the challenge of providing advanced emergent medical care at TAL sites were explored by the Department of Defense (DOD) and the National Aeronautics and Space Administration (NASA). The first option considered using a modified surgical response team, and the second involved using physician/medical technician teams. The physician/technician team concept proved the more cost-effective solution for providing medical support in these regions. Research on the logistics of blood procurement, blood refrigeration, power, air evacuation, and search and rescue (SAR) requirements led to the development of an effective TAL site astronaut medical support system.

The work presented here seeks to compare different means of providing scavenging systems for an automotive 2-stroke engine. It follows on from previous work solely investigating uniflow scavenging systems, and aims to provide context for the results discovered there as well as to assess the benefits of a new scavenging system: the reverse-uniflow sleeve-valve. For the study the general performance of the engine was taken to be suitable to power a medium-duty truck, and all of the concepts discussed here were compared in terms of indicated fuel consumption for the same cylinder swept volume using a one-dimensional engine simulation package. In order to investigate the sleeve-valve designs layout drawings and analysis of the Rolls-Royce Crecy-type sleeve had to be undertaken.

Under a program funded by the Air Force Research Laboratory (AFRL), Advanced Cooling Technologies, Inc. (ACT) has developed a series of passive thermal management techniques for cooling avionics. Many avionics packages are often exposed to environment temperatures much higher than the maximum allowable temperatures of the electronics. This condition prevents the rejection of waste heat generated by these electronics to the surrounding environment and results in significant ambient heat gain. As a result, heat must be transported to a remote sink. However, sink selection aboard modern aircraft is limited at best. Often, the only viable sink is aircraft fuel and, depending on mission profile, the fuel temperature can become too high to effectively cool avionics. As a result, the electronic components must operate at higher than intended temperatures during portions of the mission profile, which reduces component lifetime and significantly increases the probability of failure.

In a transmission for Automobiles, the driver's comfort of smooth shifting and selection of gears is a major concern for the transmission designer. To achieve this comfort, lot of work and improvement has been done in the past few years and still some more improvements are in continuation by the automobile manufacturer. Apart from the smooth shifting and selection of gears while driving, the safety of the driver is also a major concern for the vehicle manufacturer. This paper relates to a safety Interlock mechanism of vehicle gear shifter selector lever to a drive position, until a predetermined condition is satisfied. There are various gear shift pattern exists in the vehicles, which depends upon the number of gears in the gearbox. Generally, two types of gear shift pattern are commonly used in commercial vehicles. 1st-2nd, 3rd- 4th, 5th-6th, Rev and Rev-1st, 2nd-3rd, 4th-5th, 6th.

Rotational motion of the head as a mechanism for brain injury was proposed back in the 1940s. Since then a multitude of research studies by various institutions were conducted to confirm/reject this hypothesis. Most of the studies were conducted on animals and concluded that rotational kinematics experienced by the animal's head may cause axonal deformations large enough to induce their functional deficit. Other studies utilized physical and mathematical models of human and animal heads to derive brain injury criteria based on deformation/pressure histories computed from their models.

Aviation industry is striving to leverage the technological advancements in connectivity, computation and data analytics. Scalable and robust connectivity enables futuristic applications like smart cabins, prognostic health management (PHM) and AI/ML based analytics for effective decision making leading to flight operational efficiency, optimized maintenance planning and aircraft downtime reduction. Wireless Sensor Networks (WSN) are gaining prominence on the aircraft for providing large scale connectivity solution that are essential for implementing various health monitoring applications like Structural Health Monitoring (SHM), Prognostic Health Management (PHM), etc. and control applications like smart lighting, smart seats, smart lavatory, etc. These applications help in improving passenger experience, flight operational efficiency, optimized maintenance planning and aircraft downtime reduction.