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A snap-fit is a form-fitting joint, which is used to assemble plastic parts together. Snap-fits are available in different forms like a projecting clip, thicker section or legs in one part, and it is assembled to another part through holes, undercuts or recesses. The main function of the snap-fit is to hold the mating components, and it should withstand the vibration and durability loads. Snap-fits are easy to assemble, and should not fail during the assembling process. Based on the design, these joints may be separable or non-separable. The non- separable joints will withstand the loads till failure, while separable joints will withstand only for the design load. The insertion and the retention force calculation for the snaps are very essential for snap-fit design. The finite element analysis plays a very important role in finding the insertion and the retention force values, and also to predict the failure of the snaps and the mating components during this process.

Insulation of pistons in engines is aimed at reducing the heat losses and thus increasing the indicated efficiency. Thermal barrier coatings (TBCs) were used to simulate adiabatic engines with the intention not only for reduced in-cylinder heat rejection and thermal fatigue protection of underlying metallic surfaces, but also for possible reduction of engine emissions. The application of TBCs reduces the heat transfer to the engine cooling jacket through the combustion chamber surfaces (which include the cylinder head, liner, and piston crown) and piston rings. The insulation of the combustion chamber with this coating, which is ceramic based, influences the combustion process and hence the performance and exhaust emissions characteristics of the engines. In the scenario of fast rising oil prices, insulation technologies are gaining importance as they help in saving fuel.

A chemical vapor deposition method for preparing high-quality wear-resistive chromium carbide coatings was developed. The large scale CVD installation was designed. The results of the industrial tests of the chromium carbide coatings of the cylinder piston group components and nozzles are presented. The resulting coatings exhibit excellent adhesion (more than 100 MPa), low coefficient of friction (0.04 - 0.06), high microhardness (12-14 and up to 20-24 GPa depending on the experimental conditions), and wear resistance from 3 to 10 times higher as compared to electroplated chrome. The coating process is environmentally friendly, it is characterized by high adaptability and relatively low cost.

Advanced driver assistance systems like cooperative adaptive cruise control (CACC) are designed to exploit information provided by vehicle-to-vehicle (V2V) and/or infrastructure-to-vehicle (I2V) communication systems to achieve desired objectives such as safety, traffic fluidity or fuel economy. In a day to day traffic scenario, the presence of unknown disturbances complicates achieving these objectives. In particular, CACC benefits in terms of fuel economy require the prediction of the behavior of a preceding vehicle during a finite time horizon. This paper suggests an estimation method based on actual and past inter-vehicle distance data as well as on traffic and upcoming traffic lights. This information is used to train a set of nonlinear, autoregressive (NARX) models. Two scenarios are investigated, one of them assumes a V2V communication with the predecessor, the other uses only data acquired by on-board vehicle sensors.

This paper presents measurements on Vehicle to Vehicle (V2V) communication between participants in a platooning application. Platooning, according to the SARTRE concept, implies several vehicles travelling together in tight formation, with a manually driven heavy lead vehicle. The platoon being studied consists of five vehicles; two trucks in the lead and three passenger cars. The V2V-communication node in each vehicle contains an 802.11p radio at 5,9 GHz. It is used to send messages between vehicles to coordinate movements and maintain safety in the platoon. Another cooperative application that relies on V2V-communication is multiple UAVs flying in formation; as investigated in KARYON. This project also investigates cooperative autonomous vehicles. In both applications, V2V-communication is an enabling technology. Two metrics are studied to quantify the V2V-communication quality: system packet error rate and consecutive packet loss.

A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation.

In a connected vehicle, digital audio content may arrive at the audio system from sources that provide packets of audio samples with no associated sample clock. A common example is streamed internet audio. To process and play these sources, the audio system must first convert the audio stream so that it is compatible with the system's sample clock. Traditional sample-rate conversion methods are typically not capable of doing this. This paper presents and compares approaches for performing the conversion.

The newly released Distributed System Interface 3 (DSI3) Bus Standard specification defines three modulation levels form which 16 valid symbols are coded. This complex structure is best decoded with symbol pattern recognition. This paper proposes a simplification of the correlation score calculation that sharply reduces the required number of operations. Additionally, the paper describes how the pattern recognition is achieved using correlation scores and a decoding algorithm. The performance of this method is demonstrated by mean of simulations with different load models between the master and the sensors and varying noise injection on the channel. We prove than the pattern recognition can decode symbols without any error for up to 24dBm.

The substantial increase of electronic systems and processors in vehicles is increasing the already remarkable amount of software code, generating thousands of software-related recalls according to the National Highway Traffic Safety Administration (NHTSA), leading to frequent customer updates. Current software updating methods are inconvenient for customers and dealers alike, requiring a significant amount of time and expensive hardware to implement. With Wi-Fi technology and embedded modems entering vehicles, several OEMs have already taken an innovative approach with Over-The-Air (OTA) technology. OTA updating has shown to be a proven method in the telecom industry with tens of millions of phones equipped with OTA capabilities and millions of successful OTA updates performed each year, contributing to a reliable and efficient method of updating. This paper analyzes the different ways OTA is currently being used to successfully achieve in-vehicle software updates.

The last years have seen an increasing amount of innovations in the functionality of car electronics (e.g. advanced driver assistant systems (ADAS) and in-vehicle infotainment systems (IVIS)). These electrical systems are not reserved for premium cars anymore, but additionally reach mid-size, compact, and subcompact cars. The growing number of functionalities in these cars entails increasing amount of interfaces, which may confuse, overload, or annoy the driver. Accompanying this, there is a trend towards the integration of capacitive touchscreens as user interfaces. These touchscreens were implemented first in consumer electronics and had a substantial impact on the way in which users interact with technology. This in turn has led to an increased user driven demand for the technology to be implemented in other domains, even in safety-critical ones like the automotive area.

Towards developing of advanced driver specific active/passive safety systems it is important to be able to continuously evaluate driving performance variations. These variations are best captured when evaluated against similar driving patterns or maneuvers. Hence, accurate maneuver recognition in the preliminary stage is vital for the evaluation of driving performance. Rather than using simulated or fixed test track data, it is important to collect and analyze on-road real-traffic naturalistic driving data to account for all possible driving variations in different maneuvers. Towards this, massive free style naturalistic driving data corpora are being collected. Human transcription of these massive corpora is not only a tedious task, but also subjective and hence prone to errors/inconsistencies which can be due to multiple transcribers as well as lack of enough training/instructions.

The radio frequency (RF) filter is a well-known technique that has been used in communication systems for a long time. It is able to limit the selected band from receiving signals or transmitting signals. The filter can be a low-pass filter, high-pass filter, band-pass filter, and notch-filter or combined filters. This paper presents the unique Multi-Notch Filter (MNF) which takes advantages of the properties of “sinusoid wave” and “linear functions”. Since an automotive receiver is operated in noisy environments, this method is particularly useful to improve an automotive receiver's performance at the input stage when it immediately processes RF signals from an antenna. This type of filer can easily be implemented into an automotive receiver to notch out more unwanted frequency(s), such as harmonic frequencies, motor noise and very low frequencies (power line noise), which will result in better noise immunity for mobile receivers against noisy environments.

This paper describes a comparative study aimed at identifying cultural differences in automotive-HMI usability. This was part of a larger research to investigate in depth the problems users experience with vehicle-HMI in emerging-regions and help in the development of HMI design guidelines to include cultural consideration. Culture is recognised as a significant influence on user behaviour, as it correlates with certain preferences and abilities. A system may be fully usable for one group of users and environmental conditions but totally unsuitable for another. Even if a conscientious engineer designs a proper human-machine-interface for use in a given environment, the designer is often unable to foresee effects of a different culture on vehicle's HMI usability. Culture has different patterns of social behaviour and interaction which have led many researchers to develop cultural-models to describe these differences.

This paper evaluates the hidden costs of Plug-In Electric Vehicle (PEV) integration into the electric grid. The topic of PEV infrastructure is traditionally associated with the direct costs of installing chargers. However, there is also the indirect cost of infrastructure upgrades required upstream of the customer service point (meter). This is a case study of indirect infrastructure costs for PEV integration along with ways to mitigate and manage this cost transferred to customers for the Sacramento Municipal Utility District (SMUD). The costs are estimated using Monte Carlo methods applied to the geospatial and temporal diversity of SMUD's distribution network. An estimate of economic value added by Time of Use (TOU) incentives and Smart Charging for SMUD's service region is also provided.

In the paper we discuss how a single node communication interface failure in a time-triggered system can be used to model a DoS-type attack. More so, we present a design approach based on active detection of common DoS characteristics, which can serve as a template for attack detection. This approach is feasible in time-triggered systems because of the periodic and deterministic characteristics either at the fieldbus communication or application level. We support our discussion with an example case study of a vehicle braking system implementing time-triggered messages disturbed by fault injection.

Intellectual property rights and their protection is a cornerstone of the automotive value chain. The automotive industry is composed by a meshwork of tightly integrated organizations that cooperate and compete in a hierarchical marketplace. Trading know-how and other virtual assets between participants is an essential part of this business. Thereby, software as a medium to transport ideas, innovations, and technologies plays a particular role. Protection of virtual goods and their associated rights is a current issue whose solution will determine how business will be done in the future automotive market. Automotive experts and researchers agree that ICT security technologies are a vital part to implement such a market. In this paper we examine the software life cycle of an automotive Electronic Control Unit (ECU) and discuss potential threats and countermeasures for each stage.

Future automotive systems will be connected with other vehicles and information systems for improved road safety, mobility and comfort. This new connectivity establishes data and command channels between the internal automotive system and arbitrary external entities. One significant issue of this paradigm shift is that formerly closed automotive systems now become open systems that can be maliciously influenced through their communication interfaces. This introduces a new class of security challenges for automotive design. It also indirectly impacts the safety mechanisms that rely on a closed-world assumption for the vehicle. We present a new security analysis approach that helps to identify and prioritize security issues in automotive architectures. The methodology incorporates a new threat classification for data flows in connected vehicle systems.

Ti-alloy sheet is a high-modulus elastic-plastic material, about which the resilience in the cold-forming process is quite difficult to control. As a matter of fact, the procedure of cold-forming is composed of many cases such as tensile case and bending case. An expression of ultimate radius for bending-curvature is obtained based on tri-parameters elastic-plastic constitutive model. By classifying the cold-forming process, some typical cases of cold-forming are presented in this paper, and analytical solutions with a high precision of resilience for high-modulus elastic-plastic material such as Ti-alloy sheet under the different typical cases are obtained in this paper. The accurate analytical solutions of resilience for high-modulus elastic-plastic material presented in this paper will contribute to cold-forming process both in the mould-designing and optimizing of cold-forming procedure.

With the ever increasing pressure to improve the fuel economy of vehicles, there has been a corresponding interest in reducing the mass and size of vehicles. While mass is easily quantifiable, vehicle size, particularly the notion of “interior space” as perceived by the customer, is not. This paper explores different ways in which vehicle spaciousness can be quantified and explores new metrics based on customer verbatims. A novel ‘spaciousness calculator’ combines individual metrics to provide a singular holistic rating for spaciousness, useful during vehicle development. Beyond spaciousness, the paper discusses techniques to quantify the ‘packaging efficiency’ of a vehicle; this allows engineers to maximize the interior space for a given exterior size.

In electronic vehicles (EVs) or hybrid electronic vehicles (HEVs), an inverter system has a direct-current-link capacitor (DC-link capacitor) which provides reactive power, attenuates ripple current, reduces the emission of electromagnetic interference, and suppresses voltage spikes. A film capacitor has been used as the DC-link capacitor in high level power system, but the film capacitor's performance has deteriorated over operating time. The decreasing performance of the film capacitor may cause a problem when supplying and delivering energy from the battery to the vehicle's power system. Therefore, the lifetime prediction of the film capacitor could be one of critical factors in the EVs and HEVs. For this reason, the lifetime and reliability of the film capacitor are key factors to show the stability of the vehicle inverter system. There are a lot of methods to predict the lifetime of the film capacitor.