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Viewing 31 to 60 of 86934
2018-04-03
Technical Paper
2018-01-0570
Felix Ellensohn, Markus Schwienbacher, Joost Venrooij, Daniel Rixen
In periods of a growing relevance for automated driving, dynamic simulators present an appropriate simulation environment to repeat driving scenarios with good fidelity. A realistic replication of the driving dynamics is an important criterion to immerse persons in virtual environments provided by the simulator. Motion Cueing Algorithms (MCA) determine the simulator's input subject to the driving dynamics demand. The main limitations come from technical restrictions of the simulator's actuators. Typical dynamical simulators consists of a hexapod, exhibiting six degrees of freedom (DoF) to reproduce the vehicle motion in all dimensions. As its workspace dimensions are limited, an approach is to expand the simulator with redundant DoF by additional motion systems. This work introduces a global optimization scheme which is able to find an optimal motion for a driving simulator exhibiting three redundant degrees of freedom.
2018-04-03
Technical Paper
2018-01-0571
Xin Xia, Lu Xiong, Xuefeng Lin, Zhuoping Yu
Vehicle sideslip angle is significant for electronic stability control devices and hard to estimate due to the nonlinear and uncertain vehicle and tire dynamics. In this paper, based on the two track vehicle dynamic model considering the tire pneumatic trail variation, the vehicle sideslip angle estimation method was proposed. First, the extra steering angle of each wheel caused by kinematics and compliance characteristics of the steering system and suspension system was analyzed. The steering angle estimation method was designed. Since the pneumatic trail would vary with different tire slip angle, distances between the center of gravity and front&rear axle also change with the tire slip angle. Then, based on the dynamic pneumatic trail and estimated steering angle, we modified the traditional two track vehicle dynamic model using a brush tire model. This model matches the vehicle dynamics more accurately.
2018-04-03
Technical Paper
2018-01-0569
Wei Liu, Lu Xiong, Xin Xia
The estimation of vehicle key state which cannot be measured with ordinary vehicle-mounted sensors directly is the basic condition for vehicle motion following control. Especially, the accuracy and real time performance of the sideslip angle estimation have great influence on the control effect, which has been the focus in the vehicle state observation field. In this paper, the research status of the vehicle sideslip angle estimation methods is summarized: kinematics based method, dynamic based method, kinematics and dynamics fusion method, and multi-source sensors fusion method. The characteristic of different estimation algorithms is discussed. With new sensors equipment in intelligent vehicle such as GPS, camera and magnetometer, the new problems of the sideslip angle estimation including multi-rate sampling, measurement delay and attitude estimation are analyzed. Finally, the development trend of the sideslip angle estimation is prospected.
2018-04-03
Technical Paper
2018-01-0567
Achyut Vemuri, Nitin Talekar, Bhaskar Avutapalli
Durability assessment for suspension systems requires loads on each component from different road profiles. These road loads are typically obtained by testing the vehicle on the proving grounds. If a new vehicle is to be assessed for durability early in the design phase, a prototype is required which can be time consuming and expensive. Given the large number of configurations offered in the truck industry, it is not practical to measure data for each one. The only options would be to depend on generic load cases or to use a virtual method that can translate limited measurements to various configurations. If the road profiles for the proving grounds can be captured based on measurements on a few vehicle configurations, then they can be applied to new CAE full vehicle models to obtain road loads for preliminary analysis.
2018-04-03
Technical Paper
2018-01-0582
Junyi Zou, Xuexun Guo, Lin Xu, Mohamed A. A. Abdelkareem, Bian Gong, Jie Zhang, Gangfeng Tan
In this paper, a hydraulic interconnected suspension system (HIS) based on a hydraulic energy-regenerative shock absorber (HESA) is presented. At first, the structure and working principle of the suspension system is described in detail; secondly, the mathematic model of the suspension system is demonstrated to describe the hydraulic fluid characteristics, which means the relationship between the flow rate, flow velocity and oil pressure; then, a full vehicle model with 8-dof is built to research the dynamic characteristic of the HIS-HESA system; furthermore, a simulation model is established to carry out the parameter analysis of the suspension system; And in the simulation, the stability characteristic of the system is the main evaluation index, such as the anti-roll, anti-yaw, and anti-pitch performance, so the fishhook and the double lane change tests are considered as the working conditions of the simulation.
2018-04-03
Technical Paper
2018-01-0581
Wei HAN
BBW (Brake-by-wire) can increase the vehicle safety performance due to high control accuracy and fast response speed. As one solution of BBW, the novel Integrated-electro-hydraulic brake system (I-EHB) is proposed, which consists of electro-hydraulic booster and hydraulic pressure control unit. The electro-hydraulic booster is activated by an electric motor that driving linear motion mechanism to directly produce the master cylinder pressure. With electro-hydraulic booster as an actuator, the hydraulic pressure control problem is a key issue. Most literatures deal with the pressure control issue based on the feedback pressure signal measured by pressure sensor. As far as the authors are aware, none of the proposed techniques takes into account the pressure sensor unequipped BBW. In this paper, there is no pressure feedback signal, but there is only position feedback signal measured by position sensor for control law design.
2018-04-03
Technical Paper
2018-01-0579
Letian GAO, Lu Xiong, Xiang Gao
Cornering of skid-steered vehicles without steering mechanism is realized by differential drive/brake torque generated from in-wheel motors at left and right sides. Compared to traditional Ackerman steered vehicles, skid-steered vehicles consume much more energy while cornering due to greater steering resistance. So torque allocation is critical to the distributed drive skid-steered vehicles, since it influences not only steering performance, but also energy consumption. Most researches of torque allocation control for distributed drive electric skid-steered vehicles have paid much attention to tire force characteristics or efficiency characteristics of electric motors, however, torque allocation control based on unique dynamic characteristics of skid-steered vehicles are seldom studied.
2018-04-03
Technical Paper
2018-01-0590
Minghao Shen, Ting Jun Li, Weiwen Deng, Hongyu Zheng
On-ramp merging maneuver on highway requires slower passing velocity due to collision avoidance constraints. The slower velocity leads to the declination of traffic efficiency and more energy consumption. With the help of V2V technology, vehicles have access to state information of traffic vehicles and can cooperatively make decisions and motion planning. Platooning is an important application. In this article, we study a scenario where a platoon on ramp merges into another platoon on the main lane. We propose a systematic approach to planning and controlling the merging process, minimizing the energy consumption while ensuring driving safety. Due to strong coupling of system dynamics, the whole control process is made up of two consecutive steps. First a desired velocity is determined for vehicles to track, and the final merging order is planned using virtual vehicle method.
2018-04-03
Technical Paper
2018-01-0586
Balakrishna Chinta, Srinivasa Mandadapu
Understanding customer expectations is critical to satisfying customers. Holding customer clinics is one approach to set winning targets for the engineering functional measures to drive customer satisfaction. In these clinics, customers are asked to operate and interact with vehicle systems or subsystems such as doors, lift gates, shifters, and seat adjusters, and then rate their experience. From this customer evaluation data, engineers can create customer loss or preference functions. These functions let engineers set appropriate targets by balancing risks and benefits. Statistical methods such as cumulative customer loss functions are regularly applied for such analyses. In this paper, a new approach based on the Taguchi method is proposed and developed. It is referred to as Taguchi Customer Loss Function (TCLF).
2018-04-03
Technical Paper
2018-01-0596
Sughosh Rao, Timothy Seitz, Venkata Raghava Ravi Lanka, Frank Barickman, Garrick Forkenbrock, Gary Heydinger, Dennis Guenther
With the emergence of Advanced Driver Assistance Systems (ADAS), an increase in the necessity of autonomous vehicle validation is observed. However, ADAS features are much more challenging to evaluate than traditional safety features, because an understanding of the feature's response at all possible scenarios is required. In this paper, one such ADAS feature, Traffic Jam Assist (TJA) is studied. This study focused on the longitudinal behavior of autonomous vehicles, while following a lead vehicle (LV) in traffic jam scenarios. The autonomous vehicle behavior is modeled using different car-following models. In this study, three vehicles were used: 2017 Mercedes E300, 2017 Tesla S 90D, and 2017 Volvo S90. The vehicles were tested for a typical traffic scenario, where the subject vehicle (SV) is following a LV. Under this scenario, two different velocity profiles were used, one for testing and another to validate.
2018-04-03
Technical Paper
2018-01-0597
Venkata Raghava Ravi Lanka, Sughosh Rao, Timothy Seitz, Frank Barickman, Garrick Forkenbrock, Dennis Guenther, Gary Heydinger
Adaptive Cruise Control (ACC) is one of the popular Advanced Driver Assistance Systems (ADAS) features, being widely implemented in many new generation vehicles. However, evaluating safety of ACC is still challenging and requires vehicles response at various scenarios. In this paper, a method for effectively evaluating ACC is presented. Effective evaluation of ACC requires underlying control architecture and for better understanding of it, two physics-based linear mathematical models are developed. These models estimate the response of ACC in a car-following scenario, i.e., predicting the longitudinal acceleration. Developed models are listed below: 1) Single Degree of Freedom Spring Damper Model (SDM). 2) Time to Collision(TTC). These developed models are fit to Naturalistic Driving Study dataset (NDS), part of Strategic Highway Research Program-2. Next, the models are fit to newer generation autonomous vehicle data which consists of vehicles possessing ACC.
2018-04-03
Technical Paper
2018-01-0592
Günter Ehmen, Björn Koopmann, Frank Poppen, Philipp Reinkemeier, Ingo Stierand
The application of digital control in the automotive domain clearly follows an evolution with increasing complexity of both covered functions and their interaction. Advanced Driver Assistance Systems (ADAS) and Automated Driving Functions (AD) comprise modular interacting software components that typically build upon a layered architecture. As these components are generally developed by different teams, using different tools for different functional purposes and building upon different models of computation, an integration of all components guaranteeing the satisfaction of all requirements calls for coherent handling of timing properties. We propose an approach addressing this major challenge, which consists of four design paradigms. A compositional semantic framework - based on a notion of components, their interfaces and their interaction - provides the common ground.
2018-04-03
Technical Paper
2018-01-0593
Jordan A. Tunnell, Zachary D. Asher, Sudeep Pasricha, Thomas H. Bradley
Modern vehicles have incorporated numerous safety-focused Advanced Driver Assistance Systems (ADAS) in the last decade including smart cruise control and object avoidance. In this paper, we aim to go beyond using ADAS for safety, and propose to use ADAS technology to enable predictive optimal energy management and improve vehicle fuel economy. We combine ADAS sensor data with a previously developed prediction model, dynamic programming optimal energy management control, and a validated model of a 2010 Toyota Prius to explore fuel economy. First, a unique ADAS detection scope is defined based on optimal vehicle control prediction aspects demonstrated to be relevant from the literature. Next, during real world city and highway drive cycles in Denver Colorado, a camera is used to record video footage of the vehicle environment and define ADAS detection ground truth. Then, various known ADAS algorithms are combined, modified, and compared to the ground truth results.
2018-04-03
Technical Paper
2018-01-0595
Jie NI, Zhiqiang Liu PhD, Fei Dong, Jingwen Han
Based on the artificial potential field method, a elliptical influence model of obstacle vehicles was presented, and the mathematical model of lane changing trajectory planning was established including the lane boundary potential field, the multi obstacle vehicles potential field and the moving target potential field, which were used to study the trajectory planning of intelligent vehicle lane changing under the freeway scene. Taking the actual change scene as the prototype, the model was used to track the trajectory, the result shows that the planning trajectory is highly consistent with real one in good lane chaning conditions. Load the trajectory into CARSIM software to simulate, the simulation results show that the actual trajectory is consistent with the target trajectory, the front wheel steering angle, lateral acceleration are all satisfied with the dynamic constraint of vehicle, and the vehicle has well stability and comfort.
2018-04-03
Technical Paper
2018-01-0605
Julian Schatz, Manuel Eser, Philip Feig, Johann Gwehenberger, Marcel Borrack, Markus Lienkamp
The effectiveness of ADAS addressing property damage has an increasing impact on car manufacturers, insurers and customers, as accident avoidance or mitigation can lead to loss reduction. In order to obtain benefits, it is essential that ADAS primarily address monetarily relevant accident scenarios. Furthermore, sensor technologies and algorithms have to be configured in a way that relevant accident situations can be sufficiently avoided at reasonable system costs. A new methodology is developed to identify and configure monetarily effective parameters for ADAS at parking and maneuvering. In the first step, ADAS requirements regarding accident occurrence are analyzed. ADAS parameters e.g. relevant accident scenarios, required crash avoidance velocities and different sensor layouts are analyzed and evaluated using a real world in-depth accident database of insurance claims provided by Allianz Center for Technology and Allianz Automotive Innovation Center.
2018-04-03
Technical Paper
2018-01-0607
Namdoo Kim, Dominik Karbowski, Aymeric Rousseau
This paper presents a framework to simulate vehicle powertrains with human or a connected and automated driving in the same environment considering traffic light information, in order to develop control algorithm for a connected and automated vehicle. Connectivity and automation provide the potential to use information about the environment and future driving to minimize energy consumption. In order to achieve this goal, the designers of control strategy need to simulate a wide range of driving situations that be able to interact with other vehicles and the infrastructure in a close-loop fashion. RoadRunner is a framework based on Autonomie software, which can simulate longitudinal movements of one or more user-defined vehicles along a user-defined route. In the first part of the paper, we provide an overview of framework on how it is organized and under what process.
2018-04-03
Technical Paper
2018-01-0606
Kaiming Yang, Xiangkun He, Di Chen
Abstract: The new concept of "human-machine shared control" provides an amazing thinking to enhance driving safety, which has been attracted a great deal of research effort in recent years. However, little attention has been paid to the nonlinearity of the shared control system brought by tire, which significantly influences the control performance under extreme driving conditions. This paper presents a novel shared steering torque control scheme to model the human-machine steering torque interaction near the vehicle's handling limit, where both driver and driver assistance system (DAS) are exerting steering torque to maneuver the vehicle. A six-order driver-vehicle dynamic system is presented to elaborate the relationship between steering torque input and vehicle lateral motion response. Particularly, we use a piecewise-affine (PWA) method to approximate the tire nonlinearity.
2018-04-03
Technical Paper
2018-01-0603
Hoon Lee, Jaihyun Lee, Sanghoon Yoo, Kwangwoo Jeong, Byungho Lee, Sejun Kim, Levent Guvenc, Mustafa Ridvan Cantas, Santhosh Tamilarasan, Nitish Chandramouli
Coasting in neutral or Sailing has been widely recognized as one of the components of eco-driving. In neutral, the vehicle’s kinetic energy is preserved to keep the vehicle moving compared to coasting in gear, creating drag on the vehicle due to pumping and friction losses from the engine reaching the wheels. The increased coasting distance may lead to better fuel economy as compared to in-gear coasting which typically uses fuel cut-off. This has already been recognized in many vehicle implementations with names like Eco-Pro or Green mode in which the vehicle is able to coast in neutral in the absence of driver input. If available, a camera can assist detecting the obstacles in front for shifting gear back to drive as there might be the need for immediate torque for collision avoidance maneuvers. This paper presents a research prototype vehicle that has been setup to investigate and further develop an advanced coasting function connecting ADAS.
2018-04-03
Technical Paper
2018-01-0613
Xian Wu, Jing Ren, Yujun Wu, Jianwang Shao
Faced with intricate traffic conditions, the single sensor has been unable to meet the safety requirements of autonomous vehicles. In the field of multi-target tracking, the number of targets detected by vision sensor is sometimes less than the current tracks while the number of targets detected by millimeter wave radar is more than the current tracks. Hence, a multi-sensor information fusion algorithm is presented by utilizing advantage of both vision sensor and millimeter wave radar. The multi-sensor fusion algorithm is based on distributed fusion strategy that each sensor processes its own measurements to generate tracks respectively. At First, vision sensor and radar are used to detect the target and to measure the range and the angle of the target. Then, each sensor generates tracks for multi-target tracking. Vision sensor uses Hungarian Algorithm for data correlation and uses Kalman Filter for target tracking in view of its characteristics.
2018-04-03
Technical Paper
2018-01-0609
Gopal Athani, Srinivasa Raju Gavarraju, Punit Jain, Shashank Addala, Satishkumar P
Engine Stop/Start System (ESS) promises to reduce greenhouse gas emissions and improve fuel economy of the vehicles. In the previous work of the Authors, emphasis was laid in bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, the actual benefits of ESS are reduced. A slightly modified control algorithm was proposed and proven for the local driving conditions in India, which was developed through Design Thinking Methodology.
2018-04-03
Technical Paper
2018-01-0611
Rebekah L. Thompson, Zhen HU, Jin Cho, Jose Stovall, Mina Sartipi
This paper presents a real-time application of see-through technology using computer vision (e.g., object detection) and Vehicle-to-X (V2X) communication (e.g., Vehicle-to-Vehicle (V2) and Vehicle-to-Infrastructure (V2I)). Our wireless communication testbed uses three access points (APs) mounted approximately 3.3 meters from the ground along a road on our campus. Each AP was connected to Chattanooga’s fiber optics internet, supporting a data transfer rate up to 10-Gpbs. Using a 5Ghz frequency, we set up vehicular communications with a seamless handover for transferring real-time data. Two web cameras acting as clients were mounted on the windshield of two of three vehicles. Each client captured and sent 30 frames per second to our server. Using multi-threaded programming, we processed both image feeds simultaneously, which is exponentially quicker than single-thread image transferring/processing.
2018-04-03
Technical Paper
2018-01-0610
Nathir Rawashdeh, Samir A. Rawashdeh
Visual odometry and mapping will be essential components in future ADAS and autonomous driving systems. In particular, visual odometry can provide localization when GPS estimates are lost or degraded, and can provide localization relative to the surrounding environment for purposes of navigation and hazard avoidance. Feature-based visual odometry algorithms extract distinct corners/features from the scene and track them over time in order to maintain an estimate of ego-motion. From prior work, it is known that odometry can fail depending on scene content. Tracking is lost when too few detected points contribute to tracking, where the remaining points are false-matches and are outliers to the motion estimator. For example, we observed that features on trees mostly fail to be tracked because they can be confused for one another and become outliers to the motion model.
2018-04-03
Technical Paper
2018-01-0005
Manoj Kumar Pant
This paper explain requirement based testing approach for ensuring the intended Automotive Software performing its functionality with a high level of confidence by satisfying the ISO 26262 functional safety standard to meeting the Aspice process assessment objectives. Requirement based testing can be achieved by performing the effectual test design in different levels of testing (UT/SIT) such as- 1. Normal Range Test case design 2. Robustness Test case design VectorCAST/Manage and Jenkins together provide a scalable approach to continuous testing of automotive software. It allows the verification and validation of the software product at the early stages of the project thus cutting down the failure cost and reducing time-to market. The major advantage of using both VectorCAST and Jenkins together is reduction of the manual effort and completion of the project in early stages.
2018-04-03
Technical Paper
2018-01-0004
Gunwant Dhadyalla, Chek Pin Yang, James Marco, Paul Jennings
Recent reports highlighted the increasing demand for new features in road-going vehicles through electronics and software. Electronic control systems are expected to respond to input demands in real-time (circa: milliseconds) to ensure occupant and road user safety and comfort. System complexity and real-time computing requirements create significant challenges in proving the robustness of control systems, here robustness is the degree to which a system can function correctly in the presence of unexpected inputs. Despite the efforts of many vehicle manufacturers, evidence shows that faults still escape to customers incurring large warranty costs. This implies that existing test methods can be ineffective with the primary focus being on requirements validation. Evidence from other industries, e.g. IT and medical, suggests that difficult to find faults manifest due to complex interactions and sequences of events which can cause race conditions.
2018-04-03
Technical Paper
2018-01-0013
Ryo Kurachi, Toshiyuki Fujikura
In recent years, the feasibility of attacks on contemporary automotive systems has already been demonstrated by many studies. In the automotive industry, to check deviations and vulnerabilities in software, static analysis, which implies analyzing software without its execution, is performed based on the coding check tools. Additionally, in order to detect abnormalities of integrated systems in early phase, the hardware in the loop simulator (HILS) environment is already used in automotive industry. Therefore, some researches discusses security testing method on HILS. Although all existing methods are effective for security testing for automotive systems, there is room for further improvement in terms of scalability and seamless testing. In this study, we designed security testing method that can integrate with requirement-based testing for virtualized automotive systems.
2018-04-03
Technical Paper
2018-01-0014
Jin Seo Park, Daehyun kim, Seokmin Hong, Hyunjung Lee, EuiJung Myeong
Several external networks like telematics, and SOTA and many in-vehicle networks by gateways and domain controllers have been increasingly introduced. However, these trends may potentially make many critical data opened, attacked and modified by hackers. These days, vehicle security has been significantly required as these vehicle security threats are related to the human life like drivers and pedestrians. Threat modeling is process of secure software development lifecycle which is developed by Microsoft. It is a systematic approach for analyzing the potential threat in software and identifying the security risk associated with software. Through threat modeling, security risk is be mitigated and eliminated. In vehicle software System, one of vulnerability can affect critical problem about safety. An approach from experience and hacking cases is not enough for analyzing the potential threat and preparing new hacking attack.
2018-04-03
Technical Paper
2018-01-0010
Sivaprasad Nandyala, Mithun Manalikandy, Sri Ragavi
Automated testing is replacing manual testing on a large scale now-a-days. Automated testing tools can execute tests, report the results and do comparison of the same with the earlier results. Model Based Design provides an application called Model Based Testing (MBT) for performing software testing. MBT will identify defects at the early stages of development unlike manual testing. It enables higher level of automation, generates large quantities of nonrepetitive useful tests and provides number of statistical measures to evaluate software quality. Models can be used to represent testing strategies or the desired behaviour of the system. Model of software can also help refine poorly defined requirements. It eliminates model defects before coding and enables automatic test case creation which helps in cost reduction and provides high quality code. The various test mechanisms in MBT are Model-in-Loop (MIL) testing, Software-in-Loop (SIL) testing and Processor-in-Loop (PIL) testing.
2018-04-03
Technical Paper
2018-01-0020
Jana Karina von Wedel, Paul Arndt
The ever increasing complexity and connectivity of driver assist functions pose challenges for both functional safety and cyber security. Several of these challenges arise not only due to the new functionalities themselves but due to the numerous interdependencies between safety and security. Safety and security goals can conflict, safety mechanisms might be intentionally triggered by attackers to negatively impact functionality or mechanisms can compete for limited resources like processing power or memory to name just some conflict potentials. But there is also the potential for synergies, both in the implementation as well as during the development. For example, both disciplines require mechanisms to check data integrity, are concerned with freedom from interference and require architecture based analyses. So far there is no consensus in the industry on how to best deal with these interdependencies in automotive development projects.
2018-04-03
Technical Paper
2018-01-0017
Narendra Kumar SS
Days are not far off, when cars will be driving by themselves. Driverless cars or Autonomous vehicles are no more a fiction. Advanced Driver Assistance Systems (ADAS) has introduced lot of intelligence into car’s electronics. Cars can sense the surrounding, understand the scenario and take intelligent decisions. Cars can talk to other cars and exchange useful information. Cars can find out the best possible route to reach the destination. All this is made possible by tens of millions of lines of code running inside modern cars. Cars have been transformed to Cyber Physical Systems (CPS). They have more than hundred microcontrollers controlling all aspects of car from brake to steering to power windows. They are connected in various network topologies and are very complex. But, they are not secure. Researchers have already shown that, internal networks of modern cars are vulnerable to external attacks. Recent ransomware attacks have taken the IT world by storm.
2018-04-03
Technical Paper
2018-01-0019
Pallavi Kalyanasundaram, Venkatesh Kareti, Meghana Sambranikar, Narendra Kumar SS, Priti Ranadive
Controller Area Network (CAN) bus forms the major medium of communication between the Electronic Control Units (ECUs) in cars. As of today, it is impossible to imagine automobiles without CAN. Some of the recent studies reveal that it is possible to access the in-vehicle network and inject malicious messages to alter the behavior of the vehicle. Researchers have shown that, it is possible to hack a car and remotely take control of brake, steering, power window systems, etc. Hence, it becomes inevitable to implement schemes that detect anomalies and prevent attacks on CAN network. Our work explores the complete anomaly detection process for CAN network that includes the techniques followed, available tools and challenges at every stage. Various existing techniques to eliminate malicious CAN messages are also mentioned. Starting from what makes CAN protocol vulnerable, we discuss case studies about attacks on CAN network with major focus on Denial of Service (DoS) attacks.
Viewing 31 to 60 of 86934