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Viewing 181 to 210 of 16460
2017-03-28
Technical Paper
2017-01-1617
Sherif Aly
Abstract The evolution in automotive qualified electronic components, including the birth of powerful multicore System-on-Chip (SoC) platforms has fundamentally changed the approach to designing automotive electronic systems today. This evolution is not only happening on the hardware side, but also on the software design side where there has been consolidation of multiple domains onto a single SoC. This type of consolidation allows shorter time-to-market with consumer-ready features to address immediate market demands. This paper explores the reasons for this trend and available architectures for achieving consolidation. AUTOSAR on Linux is one of those architectures and has been popular in Advanced Driver Assistance Systems (ADAS) and infotainment applications, allowing complex functions to smoothly integrate into the vehicle network.
2017-03-28
Technical Paper
2017-01-1618
Max Mauro Dias Santos, Victor Ambiel, Mauro Acras, Peter Gliwa
Abstract Modern cars contain more and more safety-relevant features which require addressing safety aspects during all development phases: on the functional level, on the architectural level, during integration as well as throughout the verification. The workflow of designing safe and reliable automotive embedded systems start with appropriate requirements definitions. According to the automotive safety standard ISO 26262, functional as well as non-functional threats need to be addressed. Non-functional aspects of safe software include a sound and safe timing of the software. The right methods, tools and standards enable OEMs and suppliers developing and providing applications which meet their timing requirements and a high level of quality. We present with this paper some important aspects related to timing in automotive embedded systems as well as the major standards such as TIMMO and AUTOSAR.
2017-03-28
Technical Paper
2017-01-1619
Charles Loucks
Abstract The introduction of floating point math in Embedded Application ECU’s has made the implementation of complex math functions less error prone but not error proof. This paper shall focus on raising awareness of the pitfalls that come from the use of the basic floating point arithmetic operations, that is, Divide, Multiply, Add and Subtract. Due to the known pitfalls inherent in these basic math operations, it is proposed that a standard library with common functions appropriate for Powertrain Embedded applications (but not limited to Powertrain) be identified. This paper shall explore what these common functions will look like for both standard C code as well as the equivalent versions in Matlab™ Simulink™. The particular pitfalls this paper shall discuss are Divide-By-Zero, Overflow, Underflow and Loss-Of-Precision for both single and double precision floating point variables. This paper shall reference the IEEE-754 Floating Point standard used by most Embedded C applications.
2017-03-28
Technical Paper
2017-01-1630
Yiu Heng Cheung, Zhijia Yang, Richard Stobart
Abstract Since the first stop-start system introduced in 1983, more and more vehicles have been equipped with this kind of automatic engine control system. Recently, it was found that there is strong correlation between engine resting position and the subsequent engine start time. The utilization of the synchronization time working from a required engine stop position prior the engine start request was shown to reduce start times. Hence the position control of an engine during shutdown becomes more significant. A naturally aspirated engine was modelled using the GT-Suite modelling environment to facilitate the development of position controllers using Simulink ®. The use of respectively the throttle and a belt mounted motor generator to provide a control input was considered. Proportional-Integral-Differential (PID), sliding mode and deadbeat control strategies were each used in this study.
2017-03-28
Technical Paper
2017-01-1631
Weizhe Qian, Henry Zhang
Abstract Double Clutch Transmission system becomes more and more popular in vehicles because of the fuel saving performance, cost efficiency and comfortable feeling during gear change. To save fuel consumption and reduce CO2 emissions, pump can be driven by an electric motor for oil pressure on demand. This paper will introduce a technical solution for sensorless control of an electric pump motor used in a DCT system. Oil pressure control is fulfilled by a speed controller of the oil pump motor. Some critical control requirements for the pump motor are short and reliable start-up stage, stable and accurate speed control. This paper will elaborate on the difficulties of oil pump sensorless control, and how to solve these difficulties with minimum electronic hardware. Test results will be presented. In conclusion, the proposed sensorless control strategy can meet application requirements and meanwhile provide a cost-effective and motor parameters-independent control solution.
2017-03-28
Technical Paper
2017-01-1632
Norihiro Tsukamoto, Tomohiro Chimbe, Tomohiro Asami, Keisuke Ota, Seiji Masunaga
Abstract A new shift control system using a model-based control method for stepped automatic transmissions. Using a gear train numerical formula model, the model-based shift control system is constructed using minimum calibration parameters with feedforward and feedback controllers. It also adopts control target values for the input shaft revolution and output shaft torque, thus enabling precise control that provides the most suitable shift feeling in various driving situations and for various vehicle characteristics. Furthermore, the model-based shift control system improves robustness in terms of disturbance elements such as production tolerance, time degradation, and use environment. Toyota has adopted this model-based shift control system in its UA80/UB80 8-speed automatic transmissions for front-wheel-drive vehicles and its AGA0 10-speed automatic transmission for rear-wheel-drive vehicles. This paper describes the details of this model-based shift control system.
2017-03-28
Technical Paper
2017-01-1626
Tomas Poloni, Jianbo Lu
Abstract This paper proposes a method to make diagnostic/prognostic judgment about the health of a tire, in term of its wear, using existing on-board sensor signals. The approach focuses on using an estimate of the effective rolling radius (ERR) for individual tires as one of the main diagnostic/prognostic means and it determines if a tire has significant wear and how long it can be safely driven before tire rotation or tire replacement are required. The ERR is determined from the combination of wheel speed sensor (WSS), Global Positioning sensor (GPS), the other motion sensor signals, together with the radius kinematic model of a rolling tire. The ERR estimation fits the relevant signals to a linear model and utilizes the relationship revealed in the magic formula tire model. The ERR can then be related to multiple sources of uncertainties such as the tire inflation pressure, tire loading changes, and tire wear.
2017-03-28
Technical Paper
2017-01-1633
Eiji Kojima, Kazuhiko Kano, Hiroyuki Wado, Noriyuki Iwamori
Abstract In automotive applications, magnetic field sensors are widely used for detecting position and current. However, magnetic field sensors are required to be highly precise with good usability. To satisfy demand, we have developed a graphene Hall sensor that senses magnetic fields by the Hall effect. The sensitivity of a Hall sensor is proportional to the carrier mobility, and graphene has an extremely high carrier mobility compared with conventional materials like Si, GaAs and InSb. Thus, graphene Hall sensors are expected to give high sensitivity that will enable sensing of the Earth’s magnetic field. In addition, graphene has a low temperature dependence on carrier mobility due to its ballistic transport, so good usability in actual use is also anticipated. In this paper, we demonstrate a graphene Hall sensor made using conventional Si process technology.
2017-03-28
Technical Paper
2017-01-1628
Atsushi Ito, Masahiro Kawano, Shohei Fujita
Abstract In gasoline direct injection (GDI) systems, various injection types are needed to reduce emissions and improve fuel consumption. This requires high-precision injection in the region in which the amount of injection is small. Achieving injection of a small amount of fuel using GDI solenoid injectors requires the use of the half-lift region. In this region, however, the variation in the injection amount tends to increase due to the variation in the lift behavior of the injectors, posing the problem of how to achieve high-precision injection. To reduce the variation, we analyzed the lift timing out of the injector current and voltage signal with the ECU in an attempt to adjust the amount of injection.
2017-03-28
Technical Paper
2017-01-1629
Jing Wang, John Michelini, Yan Wang, Michael H. Shelby
Abstract Time to torque (TTT) is a quantity used to measure the transient torque response of turbocharged engines. It is referred as the time duration from an idle-to-full step torque command to the time when 95% of maximum torque is achieved. In this work, we seek to control multiple engine actuators in a collaborative way such that the TTT is minimized. We pose the TTT minimization problem as an optimization problem by parameterizing each engine actuator’s transient trajectory as Fourier series, followed by minimizing proper cost function with the optimization of those Fourier coefficients. We first investigate the problem in CAE environment by constructing an optimization framework that integrates high-fidelity GT (Gamma Technology) POWER engine model and engine actuators’ Simulink model into ModeFrontier computation platform. We conduct simulation optimization study on two different turbocharged engines under this framework with evolutionary computation algorithms.
2017-03-28
Technical Paper
2017-01-1361
Huan-Ping Chiu, Gerald Uhlenberg, Alex Wang, Jung Hsien Yen
Abstract In this study, we are presenting design considerations for the development of a LED (Light-Emitting Diode) bi-function headlight module to replace conventional HID (High-Intensity Discharge) projector modules for retrofitting or first installation purposes. The objective was to develop a projector-type module to outperform current 35 W HID light sources in both low beam and high beam, but with far less installation space. Essential features like multichip LED usage and the optical system design will be described in detail. Special care was taken for the heat management of the high-power LEDs, with optimization of the heat dissipation thermal path via printed circuit board, heatsink and active cooling by extensive Computational Fluid Dynamics simulation work (CFD). The achieved projector lumen output of greater 1300 lm in low beam and 2000 lm in high beam enables a projector module of very compact size (<1,200 cm3) to easily replace HID modules.
2017-03-28
Technical Paper
2017-01-1419
Smruti Panigrahi, Jianbo Lu, Sanghyun Hong
Abstract Characterizing or reconstructing incidents ranging from light to heavy crashes is one of the enablers for mobility solutions for fleet management, car-sharing, ride-hailing, insurance etc. While crashes involving airbag deployment are noticeable, light crashes without airbag deployment can be hidden and most drivers do not report these incidents. In this paper, we are using vehicle responses together with a dynamics model to trace back if abnormal forces have been applied to a vehicle so as to detect light crashes. The crash location around the perimeter of the vehicle, the direction of the crash force, and the severity of the crashes are all determined in real-time based on on-board sensor measurements which has further application in accident reconstruction. All of this information will be integrated to a feature called “Incident Report”, which enable reporting of minor accidents to the relevant entities such as insurance agencies, fleet managements, etc.
2017-03-28
Technical Paper
2017-01-1422
Toby Terpstra, Seth Miller, Alireza Hashemian
Abstract Photogrammetry and the accuracy of a photogrammetric solution is reliant on the quality of photographs and the accuracy of pixel location within the photographs. A photograph with lens distortion can create inaccuracies within a photogrammetric solution. Due to the curved nature of a camera’s lens(s), the light coming through the lens and onto the image sensor can have varying degrees of distortion. There are commercially available software titles that rely on a library of known cameras, lenses, and configurations for removing lens distortion. However, to use these software titles the camera manufacturer, model, lens and focal length must be known. This paper presents two methodologies for removing lens distortion when camera and lens specific information is not available. The first methodology uses linear objects within the photograph to determine the amount of lens distortion present. This method will be referred to as the straight-line method.
2017-03-28
Technical Paper
2017-01-1407
Helene G. Moorman, Andrea Niles, Caroline Crump, Audra Krake, Benjamin Lester, Laurene Milan, Christy Cloninger, David Cades, Douglas Young
Abstract Lane Departure Warning (LDW) systems, along with other types of Advanced Driver Assistance Systems (ADAS), are becoming more common in passenger vehicles, with the general aim of improving driver safety through automation of various aspects of the driving task. Drivers have generally reported satisfaction with ADAS with the exception of LDW systems, which are often rated poorly or even deactivated by drivers. One potential contributor to this negative response may be an increase in the cognitive load associated with lane-keeping when LDW is in use. The present study sought to examine the relationship between LDW, lane-keeping behavior, and concurrent cognitive load, as measured by performance on a secondary task. Participants drove a vehicle equipped with LDW in a demarcated lane on a closed-course test track with and without the LDW system in use over multiple sessions.
2017-03-28
Technical Paper
2017-01-1408
Satoshi Kozai, Yoshihiko Takahashi, Akihiro Kida, Takayuki Hiromitsu, Shinji Kitaura, Sadamasa Sawada, Gladys Acervo, Marius Ichim
Abstract A Rear Cross Traffic Auto Brake (RCTAB) system has been developed that uses radar sensors to detect vehicles approaching from the right or left at the rear of the driver’s vehicle, and then performs braking control if the system judges that a collision may occur. This system predicts the intersecting course of approaching vehicles and uses the calculated time-to-collision (TTC) to control the timing of automatic braking with the aim of helping prevent unnecessary operation while ensuring system performance.
2017-03-28
Technical Paper
2017-01-1409
Markus Schratter, Susie Cantu, Thomas Schaller, Peter Wimmer, Daniel Watzenig
Abstract Highly Automated Driving (HAD) opens up new middle-term perspectives in mobility and is currently one of the main goals in the development of future vehicles. The focus is the implementation of automated driving functions for structured environments, such as on the motorway. To achieve this goal, vehicles are equipped with additional technology. This technology should not only be used for a limited number of use cases. It should also be used to improve Active Safety Systems during normal non-automated driving. In the first approach we investigate the usage of machine learning for an autonomous emergency braking system (AEB) for the active pedestrian protection safety. The idea is to use knowledge of accidents directly for the function design. Future vehicles could be able to record detailed information about an accident. If enough data from critical situations recorded by vehicles is available, it is conceivable to use it to learn the function design.
2017-03-28
Technical Paper
2017-01-1399
Bin Wu, Xichan Zhu, Jianping Shen, Xuejun Cang, Lin li
Abstract A driver steering model for emergency lane change based on the China naturalistic driving data is proposed in this paper. The steering characteristic of three phases is analyzed. Using the steering primitive fitting by Gaussian function, the steering behaviors in collision avoidance and lateral movement phases can be described, and the stabilization steering principle of yaw rate null is found. Based on the steering characteristic, the near and far aim point used in steering phases is analyzed. Using the near and far aim point correction model, a driver steering model for emergency lane change is established. The research results show that the driver emergency steering model proposed in this paper performs well when explaining realistic steering behavior, and this model can be used in developing the ADAS system.
2017-03-28
Technical Paper
2017-01-1402
SeHwan Kim, Junmin Wang, Dennis Guenther, Gary Heydinger, Joshua Every, M. Kamel Salaani, Frank Barickman
Abstract The rapid development of driver assistance systems, such as lane-departure warning (LDW) and lane-keeping support (LKS), along with widely publicized reports of automated vehicle testing, have created the expectation for an increasing amount of vehicle automation in the near future. As these systems are being phased in, the coexistence of automated vehicles and human-driven vehicles on roadways will be inevitable and necessary. In order to develop automated vehicles that integrate well with those that are operated in traditional ways, an appropriate understanding of human driver behavior in normal traffic situations would be beneficial. Unlike many research studies that have focused on collision-avoidance maneuvering, this paper analyzes the behavior of human drivers in response to cut-in vehicles moving at similar speeds. Both automated and human-driven vehicles are likely to encounter this scenario in daily highway driving.
2017-03-28
Technical Paper
2017-01-1401
Trong-Duy Nguyen, Joseph Lull, Satish Vaishnav
Abstract In this paper, a method of improving the automated vehicle’s perception using a multi-pose camera system (MPCS) is presented. The proposed MPCS is composed of two identical colored and high frame-rate cameras: one installed in the driver side and the other in the passenger side. Perspective of MPCS varies depending on the width of vehicle type in which MPCS is installed. To increase perspective, we use the maximum width of the host vehicle as camera to camera distance for the MPCS. In addition, angular positions of the two cameras in MPCS are controlled by two separate electric motor-based actuators. Steering wheel angle, which is available from the vehicle Controller Area Network (CAN) messages, is used to supply information to the actuators to synchronize MPCS camera positions with the host vehicle steering wheel.
2017-03-28
Technical Paper
2017-01-1405
Tzu-Sung Wu
Abstract Autonomous Emergency Braking Systems (AEBS) usually contain radar, (stereo) camera and/or LiDAR-based technology to identify potential collision partners ahead of the car, such that to warn the driver or automatically brake to avoid or mitigate a crash. The advantage of camera is less cost: however, is inevitable to face the defects of cameras in AEBS, that is, the image recognition cannot perform good accuracy in the poor or over-exposure light condition. Therefore, the compensation of other sensors is of importance. Motivated by the improvement of false detection, we propose a Pedestrian-and-Vehicle Recognition (PVR) algorithm based on radar to apply to AEBS. The PVR employs the radar cross section (RCS) and standard deviation of width of obstacle to determine whether a threshold value of RCS and standard deviation of width of the pedestrian and vehicle is crossed, and to identity that the objective is a pedestrian or vehicle, respectively.
2017-03-28
Journal Article
2017-01-1403
Alexander Koenig, Michael Gutbrod, Sören Hohmann, Julian Ludwig
Abstract Highly automated driving (HAD) is under rapid development and will be available for customers within the next years. However the evidence that HAD is at least as safe as human driving has still not been produced. The challenge is to drive hundreds of millions of test kilometers without incidents to show that statistically HAD is significantly safer. One approach is to let a HAD function run in parallel with human drivers in customer cars to utilize a fraction of the billions of kilometers driven every year. To guarantee safety, the function under test (FUT) has access to sensors but its output is not executed, which results in an open loop problem. To overcome this shortcoming, the proposed method consists of four steps to close the loop for the FUT. First, sensor data from real driving scenarios is fused in a world model and enhanced by incorporating future time steps into original measurements.
2017-03-28
Journal Article
2017-01-1450
Daniel Perez-Rapela, Jason Forman, Haeyoung Jeon, Jeff Crandall
Abstract Current state-of-the-art vehicles implement pedestrian protection features that rely on pedestrian detection sensors and algorithms to trigger when impacting a pedestrian. During the development phase, the vehicle must “learn” to discriminate pedestrians from the rest of potential impacting objects. Part of the training data used in this process is often obtained in physical tests utilizing legform impactors whose external biofidelity is still to be evaluated. This study uses THUMS as a reference to assess the external biofidelity of the most commonly used impactors (Flex-PLI, PDI-1 and PDI-2). This biofidelity assessment was performed by finite element simulation measuring the bumper beam forces exerted by each surrogate on a sedan and a SUV. The bumper beam was divided in 50 mm sections to capture the force distribution in both vehicles. This study, unlike most of the pedestrian-related literature, examines different impact locations and velocities.
2017-03-28
Technical Paper
2017-01-1446
Allen Charles Bosio, Paul Marable, Marcus Ward, Bradley Staines
Abstract A dual-chambered passenger airbag was developed for the 2011 USNCAP to minimize neck loading for the belted 5th female dummy while restraining the unbelted 50th dummy for FMVSS208. This unique, patented design adaptively controlled venting between chambers based on occupant stature. A patented pressure-responsive vent on the second chamber permitted aspiration into the second chamber before a delayed outflow to the environment. The delayed flow through the pressure-responsive vent from the second chamber acted like a pressure-limiting membrane vent to advantageously reduce the injury assessment values for the HIC and the Nij for the 5th female dummy.
2017-03-28
Technical Paper
2017-01-1442
Dawei Luo, Jianbo Lu, Gang Guo
Abstract This paper proposes a low-cost but indirect method for occupancy detection and occupant counting purpose in current and future automotive systems. It can serve as either a way to determine the number of occupants riding inside a car or a way to complement the other devices in determining the occupancy. The proposed method is useful for various mobility applications including car rental, fleet management, taxi, car sharing, occupancy in autonomous vehicles, etc. It utilizes existing on-board motion sensor measurements, such as those used in the vehicle stability control function, together with door open and closed status. The vehicle’s motion signature in response to an occupant’s boarding and alighting is first extracted from the motion sensors that measure the responses of the vehicle body. Then the weights of the occupants are estimated by fitting the vehicle responses with a transient vehicle dynamics model.
2017-03-28
Technical Paper
2017-01-1441
Heungseok Chae, Kyong Chan Min, Kyongsu Yi
Abstract This paper describes design and evaluation of a driving mode decision and lane change control algorithm of automated vehicle in merge situations on highway intersection. For the development of a highly automated driving control algorithm in merge situation, driving mode change from lane keeping to lane change is necessary to merge appropriately. In a merge situation, the driving objective is slightly different to general driving situation. Unlike general situation, the lane change should be completed in a limited travel distance in a merge situation. Merge mode decision is determined based on surrounding vehicles states and remained distance of merge lane. In merge mode decision algorithm, merge availability and desired merge position are decided to change lane safely and quickly. Merge availability and desired merge position are based on the safety distance that considers relative velocity and relative position of subject and surrounding vehicles.
2017-03-28
Technical Paper
2017-01-1439
John C. Steiner, Christopher Armstrong, Tyler Kress, Tom Walli, Ralph J. Gallagher, Justin Ngo, Andres Silva
Abstract The use of the United States’ Global Positioning System (GPS) to assist with the management of large commercial fleets using telematics is becoming commonplace. Telematics generally refers to the use of wireless devices to transmit data in real time back to an organization. When tied to the GPS system telematics can be used to track fleet vehicle movements, and other parameters. GPS tracking can assist in developing more efficient and safe operations by refining and streamlining routing and operations. GPS based fleet telematics data is also useful for reducing unnecessary engine idle times and minimizing fuel consumption. Driver performance and policy adherence can be monitored, for example by transmitting data regarding seatbelt usage when there is vehicle movement. Despite the advantages for fleet management, there are limitations in the logged data for position and speed that may affect the utility of the system for analysis and reconstruction of traffic collisions.
2017-03-28
Technical Paper
2017-01-1437
William Bortles, Sean McDonough, Connor Smith, Michael Stogsdill
Abstract The data obtained from event data recorders found in airbag control modules, powertrain control modules and rollover sensors in passenger vehicles has been validated and used to reconstruct crashes for years. Recently, a third-party system has been introduced that allows crash investigators and reconstructionists to access, preserve and analyze data from infotainment and telematics systems found in passenger vehicles. The infotainment and telematics systems in select vehicles retain information and event data from cellular telephones and other devices connected to the vehicle, vehicle events and navigation data in the form of tracklogs. These tracklogs provide a time history of a vehicle’s geolocation that may be useful in investigating an incident involving an automobile or reconstructing a crash. This paper presents an introduction to the type of data that may be retained and the methods for performing data acquisitions.
2017-03-28
Technical Paper
2017-01-1434
Dongran Liu, Marcos Paul Gerardo-Castro, Bruno Costa, Yi Zhang
Abstract Heart rate is one of the most important biological features for health information. Most of the state-of-the-art heart rate monitoring systems rely on contact technologies that require physical contact with the user. In this paper, we discuss a proof-of-concept of a non-contact technology based on a single camera to measure the user’s heart rate in real time. The algorithm estimates the heart rate based on facial color changes. The input is a series of video frames with the automatically detected face of the user. A Gaussian pyramid spatial filter is applied to the inputs to obtain a down-sampled high signal-to-noise ratio images. A temporal Fourier transform is applied to the video to get the signal spectrum. Next, a temporal band-pass filter is applied to the transformed signal in the frequency domain to extract the frequency band of heart beats. We then used the dominant frequency in the Fourier domain to find the heart rate.
2017-03-28
Technical Paper
2017-01-1428
Berkan Guleyupoglu, Ryan Barnard, F. Scott Gayzik
Abstract Computational modeling of the human body is increasingly used to evaluate countermeasure performance during simulated vehicle crashes. Various injury criteria can be calculated from such models and these can either be correlative (HIC, BrIC, etc.) or based on local deformation and loading (strain-based rib fracture, organ damage, etc.). In this study, we present a method based on local deformation to extract failed rib region data. The GHMBC M50-O model was used in a Frontal-NCAP severity sled simulation. Failed Rib Regions (FRRs) in the M50-O model are handled through element deletion once the element surpasses 1.8% effective strain. The algorithm central to the methodology presented extracts FRR data and requires 4-element connectivity to register a failure. Furthermore, the FRRs are localized to anatomical sections (Lateral, Anterior, and Posterior), rib level (1,2,3 etc.) and element strain data is recorded.
2017-03-28
Technical Paper
2017-01-1503
Jared Johan Engelbrecht, Tony Russell Martin, Piyush M. Gulve, Nagarjun Chandrashekar, Amol Dwivedi, Peter Thomas Tkacik, Zachary Merrill
Abstract Most commercial heavy-duty truck trailers are equipped with either a two sensor, one modulator (2S1M) or four sensors, two modulator (4S2M) anti-lock braking system (ABS). Previous research has been performed comparing the performance of different ABS modules, in areas such as longitudinal and lateral stability, and stopping distance. This study focuses on relating ABS module type and wheel speed sensor placement to trailer wheel lock-up and subsequent impact to tire wear for tandem axle trailers with the Hendrickson air-ride suspension. Prior to tire wear inspection, functionality of the ABS system was testing using an ABS scan tool communicating with the SAE J1587 plug access port on the trailer. Observations were documented on trailers using the 2S1M system with the wheel speed sensor placed on either the front or rear axle of a tandem pair.
Viewing 181 to 210 of 16460