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The Chevrolet Volt is an electric vehicle with extended-range that is capable of operation on battery power alone, and on engine power after depletion of the battery charge. First generation Chevrolet Volts were driven over half a billion miles in North America from October 2013 through September 2014, 74% of which were all-electric [1, 12]. For 2016, GM has developed the second-generation of the Volt vehicle and “Voltec” propulsion system. By significantly re-engineering the traction power inverter module (TPIM) for the second-generation Chevrolet Volt extended-range electric vehicle (EREV), we were able to meet all performance targets while maintaining extremely high reliability and environmental robustness. The power switch was re-designed to achieve efficiency targets and meet thermal challenges. A novel cooling approach enables high power density while maintaining a very high overall conversion efficiency.

Many vehicles are currently equipped with active safety systems that can detect vulnerable road users like pedestrians and bicyclists, to mitigate associated conflicts with vehicles. With the advancements in technologies and algorithms, detailed motions of these targets, especially the limb motions, are being considered for improving the efficiency and reliability of object detection. Thus, it becomes important to understand these limb motions to support the design and evaluation of many vehicular safety systems. However in current literature, there is no agreement being reached on whether or not and how often these limbs move, especially at the most critical moments for potential crashes. In this study, a total of 832 pedestrian walking or cyclist biking cases were randomly selected from one large-scale naturalistic driving database containing 480,000 video segments with a total size of 94TB, and then the 832 video clips were analyzed focusing on their limb motions.

Development pace of new embedded projects often requires usage of model-based design process (MBD). More individuals start using MBD without previous experience with tools and new processes. Matlab/Simulink/Stateflow is a common tool that is used in control applications in automotive and airspace industries. Because of its complexity, the tool has a steep learning curve. Therefore, it is vitally important to set the MBD environment that allows persons to develop real-life projects even without a deep knowledge of the tool. The quality of the product should not be compromised and the development time should not be extended due to the initial lack of knowledge of the tool by the developers. The shifting to MBD leads to changes of roles and responsibilities of algorithm designers and software implementers. This shift is due to ability of creating of efficient production code by code generators.

Audio playbacks are mechanisms which read data from a storage medium and produce commands and signals which an audio system turns into music. Playbacks are constantly changed to meet market demands, requiring that the control software be updated quickly and efficiently. This paper reviews a 12 month project using the MATLAB/Simulink/Stateflow environment for model-based development, system simulation, autocode generation, and hardware-in-the-loop (HIL) verification for playbacks which read music CDs or MP3 disks. Our team began with a “clean slate” approach to playback architecture, and demonstrated working units running production-ready code. This modular, layered architecture enables rapid development and verification of new playback mechanisms, thereby reducing the time needed to evaluate playback mechanisms and integrate into a complete infotainment system.

As the speed and memory capabilities of microprocessors have increased, it has become more popular for the signal conditioning of knock sensor outputs to be performed entirely within the microprocessor. One method of this signal conditioning process utilizes the Discrete Fourier Transform (DFT). It is common for systems that use this method to limit the knock detection window to one length across all RPM and load points to reduce computation and memory constraints on the processor. This paper will summarize this method and explain a further enhancement, variable window length, that may become more popular as processor capabilities increase.

In this paper we present a fast symmetry search and filtering algorithm for monocular vision based pedestrian candidate detection application. First the ROI of symmetry search is focused on the pedestrian leg region, where the background is relatively simple ground plane. Afterward, the search region is divided into 2 × 4 sub blocks and symmetry density and distribution of each sub block is calculated. Finally, by comparing the symmetry density and distribution of the sub blocks, the correct symmetry axis of the pedestrian candidate is search and also some no-pedestrian candidates are filtered out. The results shown in this method are fast, cost effective and well suited for real-time vision applications.

Automotive radar application is a focus in active traffic safety research activities. And accurate lateral position estimation from the leading target vehicle through radar is of great interest. This paper presents a method based on the regression tree, which estimates the rear centroid of leading target vehicle with a long range FLR (Forward Looking Radar) of limited resolution with multiple radar detections distributed on the target vehicle. Hours of radar log data together with reference value of leading vehicle's lateral offset are utilized both as training data and test data as well. A ten-fold cross validation is applied to evaluate the performance of the generated regression trees together with fused decision forest for each percentage of the training data.

The FCC allocated the 5.9 GHz spectrum to enhance the safety and productivity of the nations transportation system. Dedicated Short Range Communication (DSRC) is a medium range wireless communication protocol that supports vehicle-to-vehicle, vehicle-to-roadside, and roadside-to-vehicle communication. It enables both public safety and licensed private transactions. DSRC contrasts cellular and Wi-Fi by providing fast acquisition, low latency communication in a relatively close communication range. IEEE is developing the Wireless Access in Vehicular Environment (WAVE) communication standards to provide the groundwork for DSRC and enable seamless, interoperable services. The WAVE architecture includes IEEE P1609.1 (Application layer), IEEE P1609.2 (Security layer), IEEE P1609.3 (Network layer), IEEE P1609.4 (Upper MAC Layer), and IEEE 802.11p (Lower MAC and Physical layers).

Vehicle Infrastructure Integration (VII) is an initiative of the US Department of Transportation to provide communications among vehicles and between vehicles and roadside infrastructure in order to increase the safety and productivity of transportation systems. It makes use of but is not restricted to the 5.9 GHz Dedicated Short Range Communication (DSRC) spectrum. There are 3 major categories of applications for VII - Highway Safety, Vehicular Mobility, and Consumer & Commercial Services. There are currently approximately 42,000 traffic fatalities a year in the United States. Reducing deaths, injuries and property damage is of the highest priority in the development of VII applications. Electronic Brake Warning, Signal Phase and Timing, and Collision Detection are among the applications dedicated to improving highway safety. Increasing traffic volume is outpacing the addition of new roadway capacity, resulting in increasing delays, congestion and frustration.

Nomadic mobile consumer electronic (CE) devices are growing in functionality and popularity. Some of these devices, such as navigation systems, are being used in vehicles as a lower cost alternative to integrated vehicle options. Other devices, such as MP-3 players, are becoming the preferred source of music on the go. Wireless nomadic devices are now capable of accessing E-mail and other Internet-based functions. Automakers are beginning to recognize the importance of integrating support for such devices to facilitate their use in vehicles. A key element of this integration is the ability of the vehicle HMI to support both the operation of nomadic devices as well as the display of content from such devices. This paper presents an example of how a nomadic device can be properly integrated with the vehicle HMI using the AMI-C HMI architecture. In particular, a commercial nomadic device was used to stream MP3 content to a vehicle radio using an 802.11 wireless connection.

This work proposes a new method to design crashworthiness structures that made of functionally graded cellular (porous) material. The proposed method consists of three stages: The first stage is to generate a conceptual design using a topology optimization algorithm so that a variable density is distributed within the structure minimizing its compliance. The second stage is to cluster the variable density using a machine-learning algorithm to reduce the dimension of the design space. The third stage is to maximize structural crashworthiness indicators (e.g., internal energy absorption) and minimize mass using a metamodel-based multi-objective genetic algorithm. The final structure is synthesized by optimally selecting cellular material phases from a predefined material library. In this work, the Hashin-Shtrikman bounds are derived for the two-phase cellular material, and the structure performances are compared to the optimized structures derived by our proposed framework.

As part of active safety systems for reducing bicyclist fatalities and injuries, Bicyclist Pre-Collision System (BPCS), also known as Bicyclist Autonomous Emergency Braking System, is being studied currently by several vehicles manufactures. This paper describes the development of a surrogate bicyclist which includes a surrogate bicycle and a surrogate bicycle rider to support the development and evaluation of BPCS. The surrogate bicycle is designed to represent the visual and radar characteristics of real bicyclists in the United States. The size of bicycle surrogate mimics the 26 inch adult bicycle, which is the most popular adult bicycle sold in the US. The radar cross section (RCS) of the surrogate bicycle is designed based on RCS measurement of the real adult sized bicycles.

Pedestrian Automatic Emergency Braking (PAEB) for helping avoiding/mitigating pedestrian crashes has been equipped on some passenger vehicles. Since approximately 70% pedestrian crashes occur in dark conditions, one of the important components in the PAEB evaluation is the development of standard testing at night. The test facility should include representative low-illuminance environment to enable the examination of the sensing and control functions of different PAEB systems. The goal of this research is to characterize and model light source distributions and variations in the low-illuminance environment and determine possible ways to reconstruct such an environment for PAEB evaluation. This paper describes a general method to collect light sources and illuminance information by processing large amount of potential collision locations at night from naturalistic driving video data.

According to the U.S. National Highway Traffic Safety Administration, 743 pedal cyclists were killed and 48,000 were injured in motor vehicle crashes in 2013. As a novel active safety equipment to mitigate bicyclist crashes, bicyclist Pre-Collision Systems (PCSs) are being developed by many vehicle manufacturers. Therefore, developing equipment for evaluating bicyclist PCS is essential. This paper describes the development of a bicycle carrier for carrying the surrogate bicyclist in bicyclist PCS testing. An analysis on the United States national crash databases and videos from TASI 110 car naturalistic driving database was conducted to determine a set of most common crash scenarios, the motion speed and profile of bicycles. The bicycle carrier was designed to carry or pull the surrogate bicyclist for bicycle PCS evaluation. The carrier is a platform with a 4 wheel differential driving system.

This work introduces a new Advanced Layered Composite (ALC) design that redirects impact load through the action of a lattice of 3D printed micro-compliant mechanisms. The first layer directly comes in contact with the impacting body and its function is to prevent an intrusion of the impacting body and uniformly distribute the impact forces over a large area. This layer can be made from fiber woven composites imbibed in the polymer matrix or from metals. The third layer is to serve a purpose of establishing contact between the protective structure and body to be protected. It can be a cushioning material or a hard metal depending on the application. The second layer is a compliant buffer zone (CBZ) which is sandwiched between two other layers and it is responsible for the dampening of most of the impact energy.

With the advent of active safety technologies in the automotive industry, a need to record and replay the actual on-road vehicular scenario has risen, especially in systems involving camera-based vision. The primary objective of the paper is to propose a design of a system for real-time video acquisition. Hence, a design for a Camera Hardware simulator has been proposed in this paper. The system involves a camera that captures visual information through its image sensor. The system is designed such that it can do direct display; that is, it can generate vertical and horizontal synchronization signals, as per the specification of the camera and it can buffer the pixel clock coming from the camera and send it to another system that uses the video information being received such as an in-vehicle display to display it. It also includes the ability to record the incoming data stream in a computer for offline processing.

Through the use of finite-element modeling, pressure patterns on the underside of seat foam can be computed for a variety of occupants and seating positions. A design tool has been created which allows an engineer to evaluate different layouts for a pressure-sensing bladder in just minutes. This is important to meet FMVSS-208 safety regulations for vehicles sold in the US. Further, an artificial intelligence search engine has been applied to this problem to achieve near-optimal performance given the constraints of the seat design. Results are shown and compared with the traditional manual method of layout design.

Since the end of the 1990s, model-based development processes have increasingly been adopted for the development of automotive embedded control software. One of the main goals of this approach is a reduction of project development time. This reduction is achieved through the use of executable modeling and autocoding. Due to the current constraints for a majority of embedded controllers on microprocessor memory and throughput, efficient production-quality code can not be generated from an executable model with the push of a button. The autocoding process requires manual setting of the software properties for the model's blocks and components by a software professional. Once the code is generated, code verification is needed. Although in many cases autocode generation and verification stages take less time to execute as compared to handcoding techniques, they still require substantial time to perform.

Driver error is a major cause of vehicle accidents and fatalities. Many of these accidents are related to impaired driver cognition because of fatigue, drowsiness, stress, or mental workload. Physiological parameters such as heart rate and respiration rate are useful for monitoring the cognitive state of a vehicle driver. The Delphi Passive Occupant Detection System (PODS) is passive, non-invasive and non-intrusive. We studied the PODS AC output to explore its utility for measuring occupant physiological parameters in a static environment. We demonstrated that with suitable filtering, amplifying, and signal processing, PODS AC signals can give respiration rate, heart rate and heart rate variability.

The evolution of car radio in the past seven decades is a perfect illustration of the convergence of diverse technical fields: RF electronics, mobile wireless communications, the Internet, personal computers, consumer electronics, and automotive human machine interfaces. The early part of the radio evolution was driven by the need to improve the received audio signal quality while in the past two decades the driver has been to increase the channel capacity and to enhance the degree of personalization. Besides traditional AM/FM programming, today's radios also play a variety of media such as cassette tape, CD, MP3, DVD-A etc. as well as over 100 channels of satellite digital audio programs. Going forward, we believe that the radio will continue to be the entertainment center of the vehicle, and that the consumers are expecting to have access to personalized information anywhere and anytime.