Photographs and video recordings of vehicle crashes and accident sites are more prevalent than ever, with dash mounted cameras, surveillance footage, and personal cell phones now ubiquitous. The information contained in these pictures and video provide critical information to understanding how crashes occurred, and in analyzing physical evidence. This course teaches the theory and techniques for getting the most out of digital media, including correctly processing raw video and photographs, correcting for lens distortion, and using photogrammetric techniques to convert the information in digital media to usable scaled three-dimensional data.
This seminar is offered in China only and presented in Mandarin Chinese. The course materials are bilingual (English and Chinese). RTCA DO-178C is the worldwide accepted standard for civil aviation software development and certification. Compliance with the objectives of DO-178C is the primary means for meeting airworthiness requirements and obtaining approval of airborne software in TC/STC/TSO, etc. Even after learning the DO-178C, many people said they still lack of experience and still find it difficult to produce DO-178C compliant airborne software in real applications.
This seminar is offered in China only and presented in Mandarin Chinese. The course materials are bilingual (English and Chinese). With the development of Chinese civil aviation industry, more and more people realized the importance of airborne software. During the certification process of previous ARJ21 aircraft, airborne software had captured many concerns. Nowadays the certification process of C919 aircraft has also reached its peak after its maiden flight.
Crash reconstruction is a scientific process that utilizes principles of physics and empirical data to analyze the physical, electronic, video, audio, and testimonial evidence from a crash to determine how and why the crash occurred. This course will introduce this reconstruction process as it gets applied to various crash types - in-line and intersection collisions, pedestrian collisions, motorcycle crashes, rollover crashes, and heavy truck crashes. Methods of evidence documentation will be covered. Analysis methods will also be presented for electronic data from event data recorders and for video.
Autonomous driving is currently one of the most challenging Artificial Intelligence (AI) problems as it requires combination of state-of-the-art solutions in multiple areas including computer vision, sensor fusion, control theory and software engineering. Deep learning has been pivotal to solving some of these problems, especially in computer vision. This enabled some autonomous vehicle companies started leveraging the benefits of deep learning for creating smooth, natural, human-like motion planning systems. In particular, the plethora of driving data captured from modern cars is a key enabler for training data-driven path planning systems. , Developing deep learning-powered systems relies heavily on big and high-quality data required for training of the models, in which the intrinsic statistics of the data that the model is trained on can result in different agent behavior in different scenarios.
Nowadays simulation of the fatigue life is an essential part of the development of components in the automotive and machinery industry. Weak points can be identified fast and reliable with respect to stiffness, strength and lightweight. A pure virtual optimization of the design can be performed without the need of prototypes. Only for the production release a final test is necessary. A lot of parameters influence the fatigue life as the local stress, material, surface roughness, size of the component, temperature etc. Notches have the strongest impact on fatigue life, depending on radius and shape. Stresses at the notch base are increased because the load flow is forced through a reduced cross section, or changes its direction around an inwardly curved edge. But notches cause not only an increase of the local stress. Also, the local fatigue strength is increased because of a support effect from the neighboring areas, where the stress is already reduced.
The increasing complexity of vehicle electronics and software is bringing an abundance of vehicle health related challenges, including quality issues and increasing costs of warranty claims, recalls, maintenance, and downtime. This negatively impacts both OEM and fleet profitability, user experience, and end customer costs. In order to reduce OEM costs and the total cost of ownership for consumers and fleets, new methods are needed to detect, predict, and diagnose vehicle health issues. Existing vehicle health management solutions rely on diagnostics trouble codes (DTC) and limited amounts of telematics data. These solutions can detect known failure modes using hard-coded signal behavior validation rules that are frequently based on thresholds. They also provide alerts based on pre-defined error codes. However, they are unable to detect and diagnose unforeseen failure modes that do not have hard-coded rules, nor can they prognose future vehicle health issues.
In 1930, John Maynard Keynes predicted, that due to software and automation, 15-hour work weeks would be a reality by the end of the century. While that envisioned “utopia” has not been realized, Mr. Keynes did have the radical vision to imagine a pretty radical low code highly automated future - one to which the future of software in mobility arguably depends on. So, what went wrong? Well, its not about as much about what went wrong but about how adoption is taking place and how it needs to change. In any software development, no matter where in history, as soon as software testing became a hot topic, automation tools started springing up and then "selective parts" that were iterative and time-consuming in the software were automated away. This begs several questions. The first and obvious, why automate these parts - and the second - whether software developers are making themselves obsolete by building automation tools.
The CAE industry always moves towards new ways to improve the productivity, efficiency and to reduce the solution times. Conventional method of Cohesive Zone Modelling has drawback of higher computation and modelling time. Due to this problem, sometimes Engineers need to avoid simulations and rely only on some sort of approximation of crack from previous designs. This approximation can lead to either product failure or overdesign of the product. A new approach is discussed in this paper to simulate crack initiation and propagation with Cohesive Zone Modelling. Conventional method uses Cohesive zone modelling with Hex or Penta elements by assigning material with cohesive properties, which increases computation and modelling time. The new approach models Cohesive zone as contact between two bodies, thus eliminating the need to use cohesive elements which will essentially reduce the computation time as well as modelling time.
Durability engineering for vehicles is about relating real operational loading to the actual strength of the product and its components. In the first part of this presentation, we show how to calculate failure probabilities and safety factors based on the load and strength distributions. We discuss the uncertainty within the estimations, which is considerably large in case of extremely small failure probabilities as required for safety critical components. In the second part, we focus on modelling and simulating the loads based on real vehicle usage, such that the resulting statistics allows to understand and quantify the usage variability. The idea is, to simulate thousands of vehicle life spans of, say, 300.000 km or 15.000 h of operation each. The input data for such simulations typically consists of a combination of geographic data (like road network, topography, road conditions, traffic data, and points of interest) and properly segmented rich data from measurement campaigns.
Passive pre-chamber ignition concept has been proven as an excellent solution to increase the combustion velocity and to allow the use of different strategies that are able to reduce pollutant emissions of internal combustion engines. Although pre-chamber combustion concept has been extensively studied, the evaluation of the heat release rate (HRR) inside the pre-chamber and its effects on the performance of the engine has not been widely investigated. In this work, newly designed passive pre-chambers with different nozzle-hole patterns, featuring combinations of radial and axial holes, were experimentally investigated in a 4-stroke single-cylinder light-duty optical engine. All the pre-chambers analyzed had a narrow throat geometry to increase the velocity of the ejected jets. An inductive and a nanosecond spark ignition systems were implemented.
Fuel chemistry plays a crucial role in the continued reduction of particulate emission (PE) and cleaner air quality while using internal combustion engines (ICE). Over the past ten years, there has been great improvements in the measurements of particulate formation indices. Examples of these indices would be the Honda Particulate Matter Index (PMI) equation and the General Motors Particulate Evaluation Index (PEI), among others. Even though there have been improvements in particulate index (PI) measurement tools, the method analysis within these tools are still very time-consuming. These methods can include the use of chromatography separation techniques such as detailed hydrocarbon analysis (DHA), which have become very popular in the petrochemical industry. A review of historical PI methods will be discussed, along with a PE comparison to a less time-consuming simulated distillation method analysis.
This work is intended to be a comprehensive technical review of existing literature and a synthesis of current understanding of the governing physics behind the interaction of multiple fuel injectio ns, ignition and combustion behavior of multiple-injections in diesel engines. Multiple-injection is a widely adopted operating strategy applied in modern compression-ignition engines, which involves various combinations of small pre-injections and post-injections of fuel before and after the main injection and splitting the main injection into multiple smaller injections. This strategy has been conclusively shown to improve fuel economy in diesel engines while achieving simultaneous NOx, soot, and combustion noise reduction in addition to a reduction in the emissions of unburned hydrocarbons and CO by preventing fuel wetting and flame quenching at the piston wall.
Understanding the fundamental details of drop/wall interactions is important to improving engine performance. Most of the drop-wall interactions studies are based on the impact of a single drop on the wall. To accurately mimic and model the real engine conditions, it is necessary to characterize spray/wall interactions with different impingement frequencies at a wide range of wall temperatures. In this study, a numerical method, based on Smoothed Particle Hydrodynamics (SPH), is used to simulate consecutive droplet impacts on a heated wall both below and above Leidenfrost temperature. Impact regimes are identified for various impact conditions by analyzing the time evolution of the post-impingement process of n-heptane drops at different impingement frequencies and wall surface temperatures. At low temperature, crown propagation and merging are dominant at low K-number whereas at high K-number there is significant splashing with the traces of liquid film on the surface.
In this study, big data analysis and user survey of driving records were conducted to investigate frequency of use and ease of operation of the regen paddle to control one-pedal driving system in electric vehicle. According to3.8 million driving record big data analysis result, it was found that the driver manipulates 3.31 times on average during a single trip, mainly during the early stages of driving. According to user observation research result, 41.8% of participates did not used or used less than 5 time of regen paddle during one single trip. Also 336 participants, which is 83%, responded that the regen paddle manipulated for one-pedal driving was inconvenient. In conclusion, because the use frequency of the regen paddle is low and the operation convenience is bad, it seems necessary to change the design of the regen paddle.
Multiple approaches have been created to enhance intra-vehicle communications security over the past three decades since the introduction of CAN. The twin pair differential-mode communications bus is tremendously robust in the face of interference, yet physical access to the bus offers a variety of potential attack vectors whereby false messages and/or denial of service are easy to achieve. This paper seeks to evaluate extensions of a common-mode watermark-based authentication technique recently developed to improve authentication on the CAN bus by considering the watermark as a side-channel communications means for high value information. We also describe a variety of higher layer algorithms, with benefits and pitfalls, for employing the watermark as a physical-layer firewall. All of these results are backed by a software-defined radio (SDR) based hardware testbed.
ISO 26262 is a functional safety standard for automotive electrical and electronic system . Hazard Analysis and Risk Assessment (HARA) is a sub-phase of the ISO26262 concept phase, which is one of most important safety activities of the ISO 26262 safety lifecycle. This paper details application of HARA for Electric Power Steering (EPS) system. First, item definition for EPS System is sketched out，which is prerequisite for the HARA. Item definition includes system description, its function, boundary, and interfaces to external systems. Then analysis procedure HARA of EPS System is detailed out ,including identifying potential hazards, developing a set of specific hazardous events, and assessing the risk of each hazardous event to determine the Automotive Safety Integration Levels (ASIL). In the end，according to analysis procedure of HARA, a set of safety goals and safety states for EPS System is proposed.
Nyquist plots are a classical means to visualize a complex vibration frequency response function. By graphing the real and imaginary parts of the response, the dynamic behavior in the vicinity of resonances is emphasized. This allows insight into how modes are coupling, and also provides a means to separate the modes. Mathematical models such as Nyquist analysis are often embedded in frequency analysis hardware. While this speeds data collection, it also removes this visually intuitive tool from the engineer’s consciousness. The purpose of this paper is to review the fundamentals of Nyquist plots and their application to structural vibration. The behavior of a single degree of freedom system will be shown to be well described by a circle on its Nyquist plot. This observation allows simple visual examination of the response of a continuous system, and the determination of quantities such as uncoupled natural frequencies, modal damping factors, and uncoupled modes shapes.