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One of the critical tasks of aircraft design is the definition of mass of aircraft's main items, and the aircraft mass distribution. Depending on the type of aircraft (e.g. commercial, general aviation, highly-maneuverable) different types of mass distribution data or trend curves are available; and in general these curves are based on the existing aircraft. But some lack of data is noticeable in terms of solar aircraft, i.e. the available information in terms of mass trends does not fulfill the needs of the designers of this type of aircraft. Considering this perspective, the main motivation of this study is to provide some information, in terms of mass trends and mass analysis for sun-powered aircraft, which could fill part of the gap, and stimulate other efforts in the same direction. Through this work, studies of mass breakdown of different examples of sun-powered aircraft are presented.

Core competitiveness is rapidly becoming of more importance in todays dynamic automotive sector. Customer demands are to be analyzed and implemented rapidly and precisely through setting clear vehicle targets for future models. Software tools deployed over a wide spectrum of applications are hereby a key resource to be acquired in the reach for efficient and accurate vehicle development. For more than two decades, Applus+ IDIADA has been using advanced measurement techniques to characterise vehicle dynamics performance. Target setting necessitates the definition of appropriate objective test programs together with subjective performance evaluations carried out by expert drivers. Their individual outputs, together with in-depth correlation between the two, form the core activity of the process.

In embedded system software architectural design, the Real-Time (RT) behavior estimation needs special care and contains many technical challenges. Most of the current approaches depend on either the engineering judgment or the actual measurements that are performed during the integration-testing phase. Both approaches may cause errors that lead to violations in the RT constraints. Both approaches are not error proof and can yield to RT constraints violations discovered during simulation of RT architectural design or during product validation. Impact on project could even be a Central Processing Unit (CPU) change. In this work, Operating System (OS) process Execution Time (ET) is considered the basic element of RT architectural design. Each process ET is predicted based on previous software releases, using Machine Learning (ML) algorithms.

In the context of the ARAMiS project, AUDI AG contributed the development of a multi-core demonstrator based on car functions already in production. For this demonstrator, these legacy car functions were ported from single-core platforms to a multi-core platform to gain real world close-to-production experience while utilizing the new technology. For complex functions with high demands for computational resources, it may be necessary to distribute computation over several cores. In this context, we investigated the parallelization of a legacy sequential AUTOSAR function. A main contribution of this work is an analysis of mechanisms provided by AUTOSAR, their limitations and, possible remedy. This paper will point out observations and experiences during the development of this demonstrator and show practical solutions for parallelization in an AUTOSAR environment.

Vehicle electronics systems will continue to become more complex and larger in scale. This causes their development to be conducted without control. As a result, system development involves things becoming intertwined with each other, like spaghetti. This has made it extremely difficult to develop an entire electronics system coherently and efficiently, from functional architecture down to physical architecture. There is thus a need to reform the development style of the electronics field to a style which will continuously and efficiently generate high-quality products. This will be achieved by dividing development into functions and components. Function development refer to developing functions that OEMs want to equip in the vehicles, that is, “what to make. Components development refers to “how to realize these components. For this activity, it is necessary to promote and accelerate platform-based development looking down at entire electronics systems.

Improving reliability and quality of software is a major aspect in automotive industry. Software reliability and quality improves by reducing bugs or defects in the software. However, finding these defects at an early stage in the software development life cycle is important to reduce rework and cost. Manually detecting defects or bugs in large code sets is time consuming and is less accurate. Hence, using static or dynamic analysis tools has become a standard practice in automotive industry. Though many such tools are commercially available, it is observed that these tools are less used for various reasons. Some of the major reasons are users need to spend considerable amount of time to learn to use these tools to get desired output reports, customized checks are required for an application that are not provided by the tool and reports are too lengthy as well as cumbersome to analyze.

Automated software testing for both hardware and software components is one of the ways industry is gaining efficiency in testing. A standard based approach can help in reducing the dependency on one particular tool chain, reduce re-training of engineers, reducing development time and increase collaboration between supplier and OEM's. Tula's Dynamic Skip Fire (DSF) technology achieves fuel efficiency by activating only the required cylinders required to achieve desired torque. Validation of the DSF algorithms requires reading of the crank, cam, spark, fuel injector, and intake and exhaust actuator positions on an individual cylinder firing opportunity. Decisions made on a cylinder by cylinder basis can be validated. The testing architecture at its core is based on the ASAM Hardware in the loop (HIL) API standard. Following the HIL-API standard gives the flexibility of choosing the best in class measurement hardware and test case management tools.

Wide varieties of vehicle Engine Management Systems are designed by different Tier#1 suppliers to meet highly complex requirements with the help of electronics. Emerging technologies and features of Engine Management Systems require a number of strategies for reducing the overall timing for verification with high quality testing. Analysis and decoding of data especially for highly critical and complex such as gasoline direct injection (GDi) engine fuel delivery output, high pressure fuel pump (HPFP), spark control output and different varieties of engine position signals are time consuming. This paper introduces Virtual Engine Control Module (VECM) technology to solve the problem of decoding complex signals and high level verification. A proposed test bench setup consists of VECM, ECM, simulator and real actuator load with complete software flashed inside the ECM.

Engine ECU testing requires sophisticated sensor simulation and event capture equipment. FPGAs are the ideal devices to address these requirements. Their high performance and high flexibility are perfectly suited to the rapidly changing test needs of today's advanced ECUs. FPGAs offer significant advantages such as parallel processing, design scalability, ultra-fast pin-to-pin response time, design portability, and lifetime upgradability. All of these benefits are highly valuable when validating constantly bigger embedded software in shorter duration. This paper discusses the collaboration between Valeo and NI to define, implement, and deploy a graphical, open-source, FPGA-based engine simulation library for ECU verification.

Presented in this research is methodology for modeling the behavior of an automotive ECU (Electronic Control Unit) to verify in a production system. The methodology of this paper is to verify the defects of ECU products during in a real operation, before the defective ECU equipped to an automobile. The performance of an ECU operation is dependent on not only the specification of a hardware device, but also a software program installed in the memory of an ECU. The software program of an ECU is able to be validated before installation, but the validation process is usually executed in a very controllable environment. In order to consider the software program which is frequently changeable in practice, the verification methodology of ECU products as the hardware device and software program integrated is required for detecting defective ECU products caused by inappropriate software program during in manufacturing processes.

As a significant control component of vehicles, automatic transmissions should have failure protection function. The failure protection function partly is determined by the hydraulic control system. However traditional design could not cover all of failures, and there is no general design method. A design method is proposed for designing the shift control oil circuit of the hydraulic control system with the failure protection function. The design method is applied to optimize the hydraulic control system of a six-speed automatic transmission. The function of the optimized hydraulic control system is confirmed by the dynamic simulation. The results show that the design method can simplify the hydraulic control system without losing any original functions. The proposed design method is proved to be suitable for all kinds of hydraulic control systems of automatic transmissions.

This paper presents a simple yet novel approach to remove redundant data from outdoor scenes, thus finding significant application in Advanced Driver Assistance Systems (ADAS). A captured outdoor scene has two main parts, the ground region consisting of the road area along with other lane markings and the background region consisting of various structures, trees, sky etc. To extract the ground region, first the yellow and white road markings are segmented based on the HSI (Hue Saturation Intensity) color model and these regions are filled with the surrounding road color. Further the background region is segmented based on the Lab (Color-opponent) color model, which shows significant improvement as compared to other color spaces. To extract the background region such as the sky or ground region, it is assumed that the top and bottom most portions of the image does not consist of useful information.

In view of the requirements of torque-based engine control and coordinated control for hybrid powertrain systems during mode switching and shifting, engine torque needs to be known. A framework for torque generated model was established, and the influencing factors of engine effective torque were analyzed. Then steady and transient performance tests of DEUTZ 6V1015 diesel engine were designed in order to get sample data to train ENNs. By use of the trained ENNs the estimations of both steady and transient friction torque and indicated thermal efficiency were completed, results were: the estimation error of friction torque and indicated thermal efficiency was less than 5%. Then the complete torque generated model was established by embedding the trained ENNs, and the estimation of effective torque was done, results were: the estimation error was less than 5%.

Gear-shift process of automatic transmission (AT) can be achieved with hydraulic control system which operates clutches or brakes' engagement or disengagement. According to the state of engagement elements, gear-shift process can be divided into torque phase and inertia phase. This article analyses gear-shift process of automatic transmission with the lever analogy and got the variation of the transmission's output torque. Then, the control principle of clutch to clutch shift is studied. This article takes power on up shift as study example and minimum of transmission output torque fluctuations during shifting as control target. Then this article analysis two control principles including inertia phase engine & transmission integrated control principle and entire shift process engine & transmission integrated control principle.

An efficient condition monitoring system provides early warning of faults by predicting them at an early stage. When a localized fault occurs in gears, the vibration signals always exhibit non-stationary behavior. The periodic impulsive feature of the vibration signal appears in the time domain and the corresponding gear mesh frequency (GMF) emerges in the frequency domain. However, one limitation of frequency-domain analysis is its inability to handle non-stationary waveform signals, which are very common when machinery faults occur. Particularly at the early stage of gear failure, the GMF contains very little energy and is often overwhelmed by noise and higher-level macro-structural vibrations. An effective signal processing method would be necessary to remove such corrupting noise and interference. In this paper, a new hybrid method based on optimal Morlet wavelet filter and autocorrelation enhancement is presented.

In modern cars, the Advanced Driver Assistance Systems (ADAS) is cardinal point for safety and regulation. The proposed method detects visual saliency region in a given image. Multiple ADAS systems require number of sensors and multicore processors for fast processing of data in real time, which leads to the increase in cost. In order to balance the cost and safety, the system should process only required information and ignore the rest. Human visual system perceives only important content in a scene while leaving rest of portions unprocessed. The proposed method aims to model this behavior of human visual system in computer vision/image processing applications for eliminating non salient objects from an image. A region is said to be salient, if its appearance is unique. In our method, the saliency in still images is computed by local color contrast difference between the regions in Lab space.

In the research field of automotive systems, Advanced Driver Assistance Systems (ADAS) are gaining paramount importance. As the significance for such systems increase, the challenges associated with it also increases. These challenges can arise due to technology, human factors, or due to natural elements (haze, fog, rain etc.). Among these, natural challenges, especially haze, pose a major setback for technologies depending on vision sensors. It is a known fact that the presence of haze in the atmosphere degrades the driver's visibility as well as the information available with the vision based ADAS. To ensure reliability of ADAS in different climatic conditions, it is vital to get back the information of the scene degraded by haze prior to analyzing the images. In this paper, the proposed work addresses this challenge with a novel and faster image preprocessing technique that can enhances the quality of haze affected images both in terms of visibility and visual perception.

In this study, a prospect of employing electric fans in a battery cooling system was investigated by means of a computational fluid dynamic (CFD) analysis. The concept was to have the fans to stimulate appropriate air flows inside the battery compartment. A rear utility space behind back passenger seats was dedicated for the battery compartment containing 100 cells of Lithium Ion batteries. Due to limited working space, a battery arrangement was conceived as a double stacking configuration. In computational analysis, the heat source model of employed batteries was obtained from the experimental work. Several potential designs of cooling patterns were investigated. The design parameters of interest were locations of inlet/outlet, and air flow rate. The performance criteria of cooling system were resulting battery temperatures, temperature distribution uniformity, required pump pressure, and structural integrity.

Wiper noise generated in the wiping process is one of the main influence factors affecting the driving comfort. Since the dynamic contact pressure of the contact between a blade and a windshield glass is difficult to be measured, it is also difficult to predict the degree of the wiper noise. In this paper, in the view of the reversal noise problem of a passenger-vehicle windscreen wiper system, the system dynamic models of the both wipers on the sides of the driver and copilot were built as considering the blade deformation and the elastic contact between the blades and the windscreen glass, including the crank pivot, the four linkage mechanism, the wiper blades, the wiper arms and the windscreen glass. The motion of the wiper system and the pressure distributions between the blades and the windscreen glass were analyzed under the half-dry condition.

Farm trucks, otherwise known as a light truck, is a vehicle used to transport agricultural products from farmers in the farm fields. Originally, farm trucks are assembled by local truck workshops using used parts of cars scrapped from abroad. It causes a serious problem in terms of quality and safety, since conventional truck garages are lack of correct engineering principles in the assembly and there has a potential risk of accidents that may occur during use. This study is focused on enhancement of life quality and safety of farm truck users from different regions in Thailand. One problem encountered in the operation is that a clutch case to cover the flywheel-clutch-module, consisting of the engine flywheel and the clutch, is mostly fabricated without applying engineering understanding. This leads to time-consuming trial and errors manufacturing process and overweight parts.