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Viewing 211 to 240 of 22743
2016-04-05
Technical Paper
2016-01-0120
Libo Huang, Huanlei Chen, Zhuoping Yu, Jie Bai
Abstract Automotive radar is the most important component in the autonomous driving system, which detects the obstacles, vehicles and pedestrians around with acceptable cost. The target tracking is one of the key functions in the automotive radar which estimates the position and speed of the targets having regarding to the measurement inaccuracy and interferences. Modern automotive radar requires a multi-target tracking algorithm, as in the radar field of view hundreds of targets can present. In practice, the automotive radar faces very complicated and fast-changing road conditions, for example tunnels and curved roads. The targets’ unpredictable movements and the reflections of the electromagnetic wave from the tunnel walls and the roads will make the multi-target tracking a difficult task. Such situation may last several seconds so that the continuous tracks of the targets cannot be maintained and the tracks are dropped mistakenly.
2016-04-05
Technical Paper
2016-01-0125
Michael Kaessmeyer, Michael Soden
Abstract Automotive engineering processes are dynamic, iterative and driven by changes. Reasons for changes on development artifacts are manifold, but the result is a new evolution step which may influence all, some, or just a single development artifact. Consequently, research on impact analysis put forth approaches to assess the adverse effects of changes. However, understanding and implementing functional changes and its consequences in the safety domain is often aggravated by dependencies between different types of development artifacts, scattered in various (tool) formats. Safety properties may change depending on the type of a modification. Thereby, connected analyses like fault trees, Failure Modes and Effects Analysis (FMEA), and safety concepts cannot be reused easily if the artifacts on which they are based on are affected by changes.
2016-04-05
Technical Paper
2016-01-0126
Philip Daian, Shinichi Shiraishi, Akihito Iwai, Bhargava Manja, Grigore Rosu
The Runtime Verification ECU (RV-ECU) is a new development platform for checking and enforcing the safety of automotive bus communications and software systems. RV-ECU uses runtime verification, a formal analysis subfield geared at validating and verifying systems as they run, to ensure that all manufacturer and third-party safety specifications are complied with during the operation of the vehicle. By compiling formal safety properties into code using a certifying compiler, the RV-ECU executes only provably correct code that checks for safety violations as the system runs. RV-ECU can also recover from violations of these properties, either by itself in simple cases or together with safe message-sending libraries implementable on third-party control units on the bus. RV-ECU can be updated with new specifications after a vehicle is released, enhancing the safety of vehicles that have already been sold and deployed.
2016-04-05
Technical Paper
2016-01-0123
Mostafa Anwar Taie, Mohamed ElHelw
Abstract The evaluation of Advanced Driver Assistance Systems (ADAS including driver assistance and active safety) has increasing interest from authorities, industry and academia. AsPeCSS active safety project concludes that good results in a laboratory test for active safety system design does not necessarily equate to an effective system in real traffic conditions. Moreover, many ADAS assessment projects and standards require physical testing on test tracks (dummy vehicles, pedestrian mannequins…), which are expensive and limit testing capabilities. This research presents a conceptual framework for on-board evaluation (OBE) of ADAS, which can be used as a cost effective evaluation in real-life traffic conditions. OBE shall monitor, record, analyze and report both internal behavior and external environment (external objects list and video stream) of ADAS under evaluation (ADASUE).
2016-04-05
Technical Paper
2016-01-0124
Andrew Scott Alden, Brian Mayer, Patrick Mcgowen, Rini Sherony, Hiroyuki Takahashi
Abstract Animal-vehicle collision (AVC) is a significant safety issue on American roads. Each year approximately 1.5 million AVCs occur in the U.S., the majority of them involving deer. The increasing use of cameras and radar on vehicles provides opportunities for prevention or mitigation of AVCs, particularly those involving deer or other large animals. Developers of such AVC avoidance/mitigation systems require information on the behavior of encountered animals, setting characteristics, and driver response in order to design effective countermeasures. As part of a larger study, naturalistic driving data were collected in high AVC incidence areas using 48 participant-owned vehicles equipped with data acquisition systems (DAS). Continuous driving data including forward video, location information, and vehicle kinematics were recorded. The respective 11TB dataset contains 35k trips covering 360K driving miles.
2016-04-05
Technical Paper
2016-01-0140
Yang Zheng, Navid Shokouhi, Nicolai Thomsen, Amardeep Sathyanarayana, John Hansen
Abstract The use of smart portable devices in vehicles creates the possibility to record useful data and helps develop a better understanding of driving behavior. In the past few years the UTDrive mobile App (a.k.a MobileUTDrive) has been developed with the goal of improving driver/passenger safety, while simultaneously maintaining the ability to establish monitoring techniques that can be used on mobile devices on various vehicles. In this study, we extend the ability of MobileUTDrive to understand the impact on driver performance on public roads in the presence of distraction from speech/voice based tasks versus tactile/hands-on tasks. Drivers are asked to interact with the device in both voice-based and hands-on modalities and their reaction time and comfort level are logged. To evaluate the driving patterns while handling the device by speech/hand, the signals from device inertial sensors are retrieved and used to construct Gaussian Mixture Models (GMM).
2016-04-05
Technical Paper
2016-01-0139
Andreas Himmler, Klaus Lamberg, Tino Schulze, Jann-Eve Stavesand
Abstract Increasing productivity along the development and verification process of safety-related projects is an important aspect in today’s technological developments, which need to be ever more efficient. The increase of productivity can be achieved by improving the usability of software tools and decreasing the effort of qualifying the software tool for a safety-related project. For safety-critical systems, the output of software tools has to be verified in order to ensure the tools’ suitability for safety-relevant applications. Verification is particularly important for test automation tools that are used to run hardware-in-the-loop (HIL) tests of safety-related software automatically 24/7. This qualification of software tools requires advanced knowledge and effort. This problem can be solved if a tool is suitable for developing safety-related software. This paper explains how this can be achieved for a COTS test automation tool.
2016-04-05
Technical Paper
2016-01-0138
Bernard Dion
Abstract Automotive manufacturers and their suppliers increasingly need to follow the objectives of ISO 26262 as it is now state-of-the art and as it is the case that an ever increasing number of active and passive safety systems are developed within cars. This has increased the need to define a safe system development process. This paper proposes a model-based approach including automatic and certified code generation to efficiently implement the embedded software that controls these systems while meeting the needed safety requirements and obeying the rules of ISO 26262.
2016-04-05
Technical Paper
2016-01-0137
Heiko Doerr, Ingo Stuermer
Abstract A key component of developing a safety-critical automotive system in compliance with ISO 26262 is developing what is known as the safety case. This delivery justifies that the system is free from unreasonable risk and that the safety requirements are complete and satisfied according to evidence from ISO 26262 work products. However, the standard provides neither practical guidance on how the safety case should be developed, nor how the safety argument should be evaluated in the functional safety assessment process. This paper discusses quality and product readiness of the system under development in the context of safety case generation. We will focus on the software level and ISO 26262-6 requirements that relate to this. We will look at the software lifecycle of the system and how to measure and deliver key data throughout this lifecycle.
2016-04-05
Journal Article
2016-01-0215
Amey Y. Karnik, Adrian Fuxman, Phillip Bonkoski, Mrdjan Jankovic, Jaroslav Pekar
Abstract An advanced powertrain cooling system with appropriate control strategy and active actuators allows greater flexibility in managing engine temperatures and operating near constraints. An organized controls development process is necessary to allow comparison of multiple configurations to select the best way forward. In this work, we formulate, calibrate and validate a Model Predictive Controller (MPC) for temperature regulation and constraint handling in an advanced cooling system. A model-based development process was followed; where the system model was used to develop and calibrate a gain scheduled linear MPC. The implementation of MPC for continuous systems and the modification related to implementing switching systems has been described. Multiple hardware configurations were compared with their corresponding control system in simulations.
2016-04-05
Technical Paper
2016-01-0266
Greg K. Caswell, James McLeish
The use of Micro Electro-Mechanical Systems (MEMS) for measuring accelerations, pressure, gyroscopic yaw rate and humidity in engine controls, inflatable restraint, braking, stability and other safety critical vehicle systems is increasing. Their use in these safety critical systems in high stress automotive environments makes ensuring their reliability and durability essential tasks, especially as the Vehicle System Functional Safety requirements of ISO-26262 are being implemented across the industry. A Design for Reliability (DfR) approach that applies Physics of Failure methods to evaluate and eliminate or mitigate susceptibilities to failure modes of a device during the design of a product is the most effective and efficient way to achieve Functional Safety levels of reliability-durability. MEMS packages exhibit several failure modes that can be predicted as a device is designed using modern Computer Aided Engineering (CAE) software tools.
2016-04-05
Technical Paper
2016-01-0241
Sina Shojaei, Simon Robinson, Andrew McGordon, James Marco
Abstract The power demand of air conditioning in PHEVs is known to have a significant impact on the vehicle’s fuel economy and performance. Besides the cooling power associated to the passenger cabin, in many PHEVs, the air conditioning system provides power to cool the high voltage battery. Calculating the cooling power demands of the cabin and battery and their impact on the vehicle performance can help with developing optimum system design and energy management strategies. In this paper, a representative vehicle model is used to calculate these cooling requirements over a 24-hour duty cycle. A number of pre-cooling and after-run cooling strategies are studied and effect of each strategy on the performance of the vehicle including, energy efficiency, battery degradation and passenger thermal comfort are calculated. Results show that after-run cooling of the battery should be considered as it can lead to significant reductions in battery degradation.
2016-04-05
Technical Paper
2016-01-0246
Rupesh Sonu Kakade, Prashant Mer
Abstract Vehicle occupants, unlike building occupants, are exposed to continuously varying, non-uniform solar heat load. Automotive manufacturers use photovoltaic cells based solar sensor to measure intensity and direction of the direct-beam solar radiation. Use of the time of the day and the position - latitude and longitude - of a vehicle is also common to calculate direction of the direct-beam solar radiation. Two angles - azimuth and elevation - are used to completely define the direction of solar radiation with respect to the vehicle coordinate system. Although the use of solar sensor is common in today’s vehicles, the solar heat load on the occupants, because of their exposure to the direct-beam solar radiation remains the area of in-car subjective evaluation and tuning. Since the solar rays travel in parallel paths, application of the ray tracing method to determine solar insolation of the vehicle occupants is possible.
2016-04-05
Technical Paper
2016-01-0611
Dejan Kihas, Daniel Pachner, Lubomir Baramov, Michael Uchanski, Priya Naik, Nassim Khaled
Abstract The interest for NOx estimators (also known as virtual sensors or inferential sensors) has increased over the recent years due to benefits attributed to cost and performance. NOx estimators are typically installed to improve On-Board Diagnostics (OBD) monitors or to lower bill of material costs by replacing physical NOx sensors. This paper presents initial development results of a virtual engine-out NOx estimator planned for the implementation on an ECM. The presented estimator consists of an airpath observer and a NOx combustion model. The role of the airpath observer is to provide input values for the NOx combustion model such as the states of the gas at the intake and exhaust manifolds. It contains a nonlinear mean-value model of the airpath suitably transformed for an efficient and robust implementation on an ECM. The airpath model uses available sensory information in the vehicle to correct predictions of the gas states.
2016-04-05
Technical Paper
2016-01-0614
Donald V. Johnson, Gregory Roth, Andrew Fedewa, Jeremy Kraenzlein, Xiaojian Yang
Abstract Delphi is developing a new combustion technology called Gasoline Direct-injection Compression Ignition (GDCI), which has shown promise for substantially improving fuel economy. This new technology is able to reuse some of the controls common to traditional spark ignition (SI) engines; however, it also requires several new sensors and actuators, some of which are not common to traditional SI engines. Since this is new technology development, the required hardware set has continued to evolve over the course of the project. In order to support this development work, a highly capable and flexible electronic control system is necessary. Integrating all of the necessary functions into a single controller, or two, would require significant up-front controller hardware development, and would limit the adaptability of the electronic controls to the evolving requirements for GDCI.
2016-04-05
Technical Paper
2016-01-0626
Benedikt Raidt
Abstract Air charge calibration of turbocharged SI gasoline engines with both variable inlet valve lift and variable inlet and exhaust valve opening angle has to be very accurate and needs a high number of measurements. In particular, the modeling of the transition area from unthrottled, inlet valve controlled resp. throttled mode to turbocharged mode, suffers from small number of measurements (e.g. when applying Design of Experiments (DoE)). This is due to the strong impact of residual gas respectively scavenging dominating locally in this area. In this article, a virtual residual gas sensor in order to enable black-box-modeling of the air charge is presented. The sensor is a multilayer perceptron artificial neural network. Amongst others, the physically calculated air mass is used as training data for the artificial neural network.
2016-04-05
Technical Paper
2016-01-0633
Yichao Guo
Abstract Per California Air Resources Board (CARB) regulations, On-board diagnostic (OBD) of vehicle powertrain systems are required to continuously monitor key powertrain components, such as the circuit discontinuity of actuators, various circuit faults of sensors, and out-of-range faults of sensors. The maturing and clearing of these continuous monitoring faults are critical to simplification of algorithm design, save of engineering cost (i.e., calibration), and reduction of warranty issues. Due to the nature of sensors (to sense different physical quantities) and actuators (to output energy in desired ways), most of OEM and supplies tend to choose different fault maturing and clearing strategy for sensors and actuators with different physics nature, such as timer-based, counter-based, and other physical-quantity-based strategies.
2016-04-05
Technical Paper
2016-01-0637
Yusheng Wang, David L.S. Hung, Hanyang Zhuang, Min Xu
Abstract The cycle-to-cycle variations of in-cylinder flow field represent a significant challenge which influence the stability, fuel economy, and emissions of engine performance. In this experimental investigation, the high-speed time-resolved particle image velocimetry (PIV) is applied to reveal the flow field variations of a specific swirl plane in a spark-ignition direct-injection engine running under two different swirl air flow conditions. The swirl flow is created by controlling the opening of a control valve mounted in one of the two intake ports. The objective is to quantify the cycle-to-cycle variation of in-cylinder flow field at different crank angles of the engine cycle. Four zones along the measured swirl plane are divided according to the positions of four valves in the cylinder head. The relevance index is used to evaluate the cycle-to-cycle variation of the velocity flow field for each zone.
2016-04-05
Technical Paper
2016-01-0638
Suresh Gadekar, Akhilendra Pratap Singh, Avinash Kumar Agarwal
Abstract In this study, 3D air-flow-field evolution in a single cylinder optical research engine was determined using tomographic particle imaging velocimetry (TPIV) at different engine speeds. Two directional projections of captured flow-field were pre-processed to reconstruct the 3D flow-field by using the MART (multiplicative algebraic reconstruction technique) algorithm. Ensemble average flow pattern was used to investigate the air-flow behavior inside the combustion chamber during the intake and compression strokes of an engine cycle. In-cylinder air-flow characteristics were significantly affected by the engine speed. Experimental results showed that high velocities generated during the first half of the intake stroke dissipated in later stages of the intake stroke. In-cylinder flow visualization indicated that large part of flow energy dissipated during the intake stroke and energy dissipation was the maximum near the end of the intake stroke.
2016-04-05
Technical Paper
2016-01-0677
Terry A. Johnson, Michael T. Leick, Ronald W. Moses
Abstract This paper describes the experimental evaluation of a prototype free piston engine - linear alternator (FPLA) system developed at Sandia National Laboratories. The opposed piston design was developed to investigate its potential for use in hybrid electric vehicles (HEVs). The system is mechanically simple with two-stroke uniflow scavenging for gas exchange and timed port fuel injection for fuel delivery, i.e. no complex valving. Electrical power is extracted from piston motion through linear alternators which also provide a means for passive piston synchronization through electromagnetic coupling. In an HEV application, this electrical power would be used to charge the batteries. The engine-alternator system was designed, assembled and operated over a 2-year period at Sandia National Laboratories in Livermore, CA.
2016-04-05
Technical Paper
2016-01-0314
Larry Michaels, Curtis G. Adams, Michael Juskiewicz
Abstract A simulation approach is defined that integrates a military mission assessment tool (One Semi-Automated Forces) with a commercial automotive control/energy consumption development tool (Autonomie). The objective is to enable vehicle energy utilization and fuel consumption impact assessments relative to US Army mission effectiveness and commercial drive cycles. The approach to this integration will be described, along with its potential to meet its objectives.
2016-04-05
Journal Article
2016-01-0149
Mehdi Jalalmaab, Mohammad Pirani, Baris Fidan, Soo Jeon
In this paper, a consensus framework for cooperative parameter estimation within the vehicular network is presented. It is assumed that each vehicle is equipped with a dedicated short range communication (DSRC) device and connected to other vehicles. The improvement achieved by the consensus for parameter estimation in presence of sensor’s noise is studied, and the effects of network nodes and edges on the consensus performance is discussed. Finally, the simulation results of the introduced cooperative estimation algorithm for estimation of the unknown parameter of road condition is presented. It is shown that due to the faster dynamic of network communication, single agents’ estimation converges to the least square approximation of the unknown parameter properly.
2016-04-05
Technical Paper
2016-01-0152
Pierre Michel, Dominik Karbowski, Aymeric Rousseau
Abstract Connectivity and automation are increasingly being developed for cars and trucks, aiming to provide better safety and better driving experience. As these technologies mature and reach higher adoption rates, they will also have an impact on the energy consumption: Connected and Automated Vehicles (CAVs) may drive more smoothly, stop less often, and move at faster speeds, thanks to overall improvements to traffic flows. These potential impacts are not well studied, and any existing studies tend to focus solely on conventional engine-powered cars, leaving aside electrified vehicles such as Hybrid Electric Vehicles (HEVs) and Battery Electric Vehicles (BEVs). This work intends to address this issue by analyzing the energy impact of various CAV scenarios on different types of electric vehicles using high-fidelity models. The vehicles-all midsize, one HEV, one BEV, and a conventional-are modeled in Autonomie, a high-fidelity, forward-looking vehicle simulation tool.
2016-04-05
Technical Paper
2016-01-0167
Hugh Luke Humphreys, Joshua Batterson, David Bevly, Raymond Schubert
Abstract The fuel efficiency improvement of a prototype Driver-Assistive-Truck-Platooning (DATP) system was evaluated using Computational Fluid Dynamics (CFD). The DATP system uses a combination of radar and GPS, integrated active safety systems, and V2V communications to enable regulation of the longitudinal distance between pairs of trucks without acceleration input from the driver in the following truck(s). The V2V linking of active safety systems and synchronized braking promotes increased safety of close following trucks while improving their fuel economy. Vehicle configuration, speed, and separation distance are considered. The objectives of the CFD analysis are to optimize the target separation distance and to determine the overall drag reduction of the platoon. This reduction directly results in fuel economy gains for all cooperating vehicles.
2016-04-05
Technical Paper
2016-01-0161
Valentin Soloiu, Imani Augusma, Deon Lucien, Mary Thomas, Roccio Alba-Flores
Abstract This study presents the design and development of a vehicle platform with intelligent sensors that has the capabilities to drive independently and cooperatively on roads. An integrated active safety system has been designed to optimize the human senses using ultrasonic infrared sensors and transmitter/receiver modules, to increase the human vision, feel and communication for increased road safety, lower congestion rates, and decrease CO2 emissions. Ultrasonic sensors mounted on the platform, emitted longitudinal 40 kHz waves and received echoes of these sound waves when an object was within its direction. The duration was converted to a distance measurement to detect obstacles as well as using distance measurement threshold values to implement adaptive cruise control. Infrared sensors equipped with an IR LED and a bipolar transistor detected a change in light intensity to identify road lanes.
2016-04-05
Technical Paper
2016-01-0163
Thomas Rothermel, Jürgen Pitz, Hans-Christian Reuss
Abstract This paper proposes a framework for semi-autonomous longitudinal guidance for electric vehicles. To lower the risk for pedestrian collisions in urban areas, a velocity trajectory which is given by the driver is optimized with respect to safety aspects with the help of Nonlinear Model Predictive Control (NMPC). Safety aspects, such as speed limits and pedestrians on the roadway, are considered as velocity and spatial constraints within prediction horizon in NMPC formulation. A slack variable is introduced to enable overshooting of velocity constraints in situations with low risk potential to rise driver acceptance. By changing the weight of slack variable, the control authority can be shifted continuously from driver to automation. Within this work, a prototypical real-time implementation of the longitudinal guidance system is presented and the potential of the approach is demonstrated in human-in-the-loop test drives in the Stuttgart Driving Simulator.
2016-04-05
Technical Paper
2016-01-0158
Toshio Ito, Arata Takata, Kenta Oosawa
Abstract Automation of vehicles can be expected to improve safety, comfort and efficiency, and is being developed in various countries. Introduction of automated driving can be ranked from 0 to 5 (0: no automation, 1: driver assistance, 2: partial automation, 3: conditional automation, 4: high automation, 5: full automation). Currently, feasible automation levels are considered to be levels 2 or 3, and human manual take-over from the automated system is needed when the automated system exceeds these levels. In this situation, time required for take-over is an important issue. This study focuses on describing driving simulator experimental results of time required for take-over. The experimental scenario is that the automated system finds an object ahead during automated driving on the highway, and issues a take-over request to the driver. The subject driver can be in the following driver situations: hands-on or hands-off the steering, and strong or weak distractions.
2016-04-05
Journal Article
2016-01-0159
Luting Wang, Chong Cao, Bo Chen
Abstract This paper studies the bi-directional power flow control between Plug-in Electric Vehicles (PEVs) and an electrical grid. A grid-tied charging system that enables both Grid-to-Vehicle (G2V) and Vehicle-to-Grid (V2G) charging/discharging is modeled using SimPowerSystems in Matlab/Simulink environment. A bi-directional AC-DC converter and a bi-directional DC-DC buck-boost converter are integrated to charge and discharge PEV batteries. For AC-DC converter control, Predictive Current Control (PCC) strategy is employed to enable grid current to reach a reference current after one modulation period. In addition, Phase Lock Loop (PLL) and a band-stop filter are designed to lock the grid voltage phase and reduce harmonics. Bi-directional power flow is realized by controlling the mode of the DC-DC converter. Simulation tests are conducted to evaluate the performance of this bi-directional charging system.
2016-04-05
Journal Article
2016-01-0160
Takayuki Shimizu, Tomoya Ono, Wataru Hirohashi, Kunihiko Kumita, Yasuhiro Hayashi
Abstract In this paper, we consider smart charging and vehicle-to-home (V2H) technologies for plugin electric vehicles coordinated with home energy management systems (HEMS) for automated demand response. In this system, plugin electric vehicles automatically react to demand response events with or without HEMS’s coordination, while vehicles are charged and discharged (i.e., V2H) in appropriate time slots by taking into account demand response events, time-ofuse rate information, and users’ vehicle usage plan. We introduce three approaches on home energy management: centralized energy control, distributed energy control, and coordinated energy control. We implemented smart charging and V2H systems by employing two sets of standardized communication protocols: one using OpenADR 2.0b, SEP 2.0, and SAE standards and the other using OpenADR 2.0b, ECHONET Lite, and ISO/IEC 15118.
2016-04-05
Technical Paper
2016-01-0154
Pritesh Jain, Purushottam Bhumre, Saakshi Jain
Abstract This paper describes the Common Automobile Program (CAP) that can be implemented to improve mass transportation. CAP is the use of automated electric vehicles using smart navigation and control technologies to improve mass transportation. In CAP, common vehicles are used by different passengers, thus, reducing the on-road traffic and also the parking space required. Various low-cost stations are to be built along specified paths and the vehicle can be used at the convenience of the commuter. Currently, buses and trains require the passengers to wait at the station and a significant amount of time is spent at intermediate stops. The vehicle in CAP runs directly from origin to destination and also eliminates the waiting time at stations. Passengers do not wait for vehicles; instead vehicles wait for the passengers. The journey starts as the passenger enters the station and selects the destination.
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