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2017-10-31
White Paper
WP-0002
The environmental impact of hydrocarbon-burning aircraft, both from the perspective of gas emissions and that of noise, is one of the main motivations for the move to electric propulsion. The added benefit from this shift to electric propulsion is that it has resulted in lowering the costs of electrical components such as motors, power electronic (PE) circuits, and batteries that are essential to this technology. This white paper seeks to explore the history, architecture, electrical components, and future trends of electric flight technology.
2017-10-08
Technical Paper
2017-01-2452
Kingsley Joel Berry, Abdrahamane Traore, Aravind Krishna, Pavankumar Gangadhar, Allan Taylor
This paper documents the electrical infrastructure design of a Hybrid Go Kart competition vehicle which includes a dual Fuel Cell power system, Ultra Capacitors for energy storage, and a dual AC induction motor capable of independent drive. The Kart was built primarily to compete in the 2009 Formula Zero international event. The vehicle model was developed in Simulink to determine whether the fuel cell and ultra-capacitor combination will be sufficient for peak transient power requirement of 36 kW. The vehicle’s functional description and performance specifications are documented including the integration of the fuel cell power modules, energy storage system, power converters, and AC motor and motor controllers.
2017-10-08
Technical Paper
2017-01-2301
Hongli Gao, Fujun Zhang, Wenwen Zeng, Tianpu Dong, Zhengkai Wang
Abstract The electronic control of direct injection fuel system, which could improve engine fuel efficiency, dynamics and engine emission performance through good atomization, precise control of fuel injection time and improvement of fuel-gas mixture, is the key technology to achieve the stratified combustion and lean combustion. In this paper, a direct injection injector that based on voice coil motor was designed aiming at the technical characteristics of one 800cc two-stroke cam-less engine. Prior to a one - dimensional simulation model of injector was established by AMEsim and the maximal fuel injection demand was met via the optimization of the main parameters of the injector, the structure of the voice coil motor was optimized by magnetic equivalent circuit method. After that, the maximal flow rate of the injector was verified by the injector bench test while the atomization characteristic of the injector was verified by using a high-speed camera.
2017-10-08
Technical Paper
2017-01-2283
Anand Prabu Kalaivanan, Gnanasekaran Sakthivel
Abstract Electronic Fuel Injection Systems have revolutionised Fuel Delivery and Ignition timing in the past two decades and have reduced the Fuel Consumption and Exhaust Emissions, ultimately enhancing the Economy and Ecological awareness of the engines. But the ignition/injection timing that commands the combustion is mapped to a fixed predefined table which is best suited during the stock test conditions. However continuous real time adjustments by monitoring the combustion characteristics prove to be highly efficient and be immune to varying fuel quality, lack of transient performance and wear related compression losses. For developing countries, Automotive Manufacturers have been Tuning the Ignition/Injection timing Map assuming the worst possible fuel quality. Conventional knock control system focus on engine protection only and doesn't contribute much in improving thermal efficiency.
2017-10-08
Technical Paper
2017-01-2286
A S Ramadhas, Punit Kumar Singh, Reji Mathai, Ajay Kumar Sehgal
Abstract Ambient temperature conditions, engine design, fuel, lubricant and fuel injection strategies influence the cold start performance of gasoline engines. Despite the cold start period is only a very small portion in the legislative emission driving cycle, but it accounts for a major portion of the overall driving cycle emissions. The start ability tests were carried out in the weather controlled transient dynamometer - engine test cell at different ambient conditions for investigating the cold start behavior of a modern generation multi-point fuel injection system spark ignition engine. The combustion data were analyzed for the first 200 cycles and the engine performance and emissions were analyzed for 300 s from key-on. It is observed that cumulative fuel consumption of the engine during the first 60 s of engine cold starting at 10 °C was 60% higher than at 25 °C and resulted in 8% increase in the value of peak speed of the engine.
2017-10-08
Technical Paper
2017-01-2302
Tobias Knorsch, Dmitrii Mamaikin, Philippe Leick, Philipp Rogler, Jin Wang, Zhilong Li, Michael Wensing
Abstract The fuel spray behavior in the near nozzle region of a gasoline injector is challenging to predict due to existing pressure gradients and turbulences of the internal flow and in-nozzle cavitation. Therefore, statistical parameters for spray characterization through experiments must be considered. The characterization of spray velocity fields in the near-nozzle region is of particular importance as the velocity information is crucial in understanding the hydrodynamic processes which take place further downstream during fuel atomization and mixture formation. This knowledge is needed in order to optimize injector nozzles for future requirements. In this study, the results of three experimental approaches for determination of spray velocity in the near-nozzle region are presented. Two different injector nozzle types were measured through high-speed shadowgraph imaging, Laser Doppler Anemometry (LDA) and X-ray imaging.
2017-10-08
Technical Paper
2017-01-2314
Genmiao Guo, Zhixia He, Qian Wang, Shenxin Sun, Zhou Chen
Abstract Study of the spray formation in vicinity of the nozzle is essential to better understand and predict the physical processes involved in the diesel atomization. The initial spray patterns were found to be different from one injection to another during our visualization experiments, which was carried out based on a long distance microscope with a high speed camera in this work. It was found that the initial spray might contain a clear single mushroom, tail region and intact liquid column, or have a tail in front of the mushroom without changing its direction. Occasionally, it presented as a double-mushroom shape, or did not include a clear mushroom. Our visualization results showed that the various spray structures were observed at different injection pressures and different injection cycles under the same injection pressure.
2017-10-08
Technical Paper
2017-01-2307
Yijie Wei, Tie Li, Bin Wang, Weiquan Shi
Lift-off length is defined as the distance from injector hole to the location where flame stabilized on a high injection pressure direct injection (DI) diesel spray. In this paper we used the high-speed (40 kHz) Schlieren and time-averaged OH chemiluminescence imaging technique to simultaneously measure the flame lift-off locations on a DI diesel spray in an optically accessible and constant-volume combustion vessel. The time-resolved development of the diesel spray acquired from the high-speed Schlieren imaging system enabled us to observe the instantaneous spray structure details of the spray flames. The OH chemiluminescence image obtained from a gated, intensified CCD video camera with different delay and width settings was used to determine the quiescent lift-off length. Experiments were conducted under various ambient temperatures, ambient gas densities, injection pressures and oxygen concentrations.
2017-10-08
Technical Paper
2017-01-2198
Zhihong Li, Guoxiu Li, Lan Wang, Hongmeng Li, Jie Wang, Haizhou Guo, Shuangyi He
The electromagnetic valve driving mechanism is the significant equipment, which plays a vital role in the unit pump injection system; therefore, the performance of the electromagnetic valve directly influences the function of the control system. Based on the operation conditions of the unit pump injection system, a steady electromagnetic valve model was modified to study the influence factors of electromagnetic force and the best combination to get the maximum electromagnetic force. The validation model was verified by experiment. The effects of some crucial parameters upon the electromagnetic force were investigated in the present paper, (including working airspace, magnetic pole’s cross-sectional area, coil position, coil turn, the armature thickness). The result shows that the electromagnetic force of the solenoid valve enhanced with the increasing driving current and reduced with the decreasing of working condition.
2017-10-08
Technical Paper
2017-01-2425
Ramit Verma, Ramdas R Ugale
Abstract On two wheelers, magneto/alternator generates either single/three phase AC power and Regulator Rectifier Unit (RRU) does regulated rectification to charge the battery. In order to face the requirements of 2-wheeler engine with respect to upcoming stringent regulations like electronic fuel injection (EFI), anti-lock braking system (ABS), automatic headlamp on (AHO) in emerging markets like India; vehicles demand more electrical power from batteries. This demands higher power from alternator and consequently from RRU. Requirement of higher output power presents challenges on regulator rectifier unit in terms of size, power dissipation management and reliability. In this paper, improved performance of MOSFET based RRU is discussed in comparison to Silicon Controlled Rectifier (SCR) based RRU. The motivation/benefits of MOSFET based design is described along with the thermal behavior and temperature coefficient performance of RRU with test results.
2017-10-08
Technical Paper
2017-01-2412
Dojoong Kim, Dong Hyeong Lee, Jong Wung Park, Soo Hyun Hwang, Wan Jae Jeon
Abstract This paper introduces a two-step variable valve actuation (VVA) mechanism equipped with an electronic switching system, which can be applied to OHC valve trains with end pivot rocker arms. The electronic switching system is driven by a dedicated solenoid and is not affected by the temperature or pressure of the engine oil. Therefore, not only can the dynamic stability be secured at the time of mode switching but the operation delay time can also be kept short enough. Several models of two-step VVA mechanisms were fabricated and the operability of the mechanism and switching system was experimentally confirmed. The two-step VVA mechanism developed in this study can also be used as a cylinder deactivation (CDA) system by assigning the lift of the low-speed cam to be zero. By attaching a roller to the portion of the rocker arm that is in contact with the base cam, the problem of pad wear, which is often present in CDA mechanism, is also fundamentally solved.
2017-10-08
Technical Paper
2017-01-2221
Peixuan Zeng, Penghao Zhang, Binyu Mei, Shiping Huang, Gangfeng Tan
Abstract:In low temperature condition, the increase of fuel viscosity, the decrease of flow-ability of lubricating oil and the decrease of storage battery performance cause the engine starting difficult. The current electrical heating method can improve the engine starting performance in low temperature condition, but it causes a negative influence on storage battery performance and exhaust emission. In this paper, a warming device uses solar energy to directly warm up the engine. The device transfers solar power into thermal energy and store it into heat reservoir and uses heat conductor to warm up the engine. By using solar power to save power, the lifespan of the engine is extended and exhaust emission is decreased. This paper find out the heat amount necessary for diesel engine through resource gathering and calculation, choose an appropriate device and design a corresponding solar warming system. Keywords: warming system, solar power, diesel engine
2017-10-08
Journal Article
2017-01-2459
Liu Xiaojun, Yu Jinpeng, Yang Xia, Wu Daoming, Jie Zhu
In the case of electric vehicles, due to the charging current limitation of lithium battery at low temperatures (below -20℃), it has been proposed to heat the battery pack up to a suitable temperature range before charging through a liquid-heating plate with PTC. However, in the low state of charge (SOC), there is a question which one could take the place of battery pack to supply power for PTC when heating. So that off-board charger has been considered to supply power for PTC detailed in this paper. In order to control the current charging to the battery pack as less as possible at low temperatures, three control strategy models are established and compared: First, BMS controls the charging request current value which is send to off-board charger as a signal, and equals to the working current of PTC. Second, BMS controls the charging request voltage value which is slightly lower than the battery pack voltage.
2017-10-08
Technical Paper
2017-01-2367
Ganesan Mahadevan, Sendilvelan Subramanian
Abstract Control of harmful emissions during cold start of the engine has become a challenging task over the years due to the ever increasing stringent emission norms. Positioning the catalytic converter closer to the exhaust manifold is an efficient way of achieving rapid light-off temperature. On the other hand, the resulting higher thermal loading under high-load engine operation may substantially cause thermal degradation and accelerate catalyst ageing. The objective of the present work is to reduce the light-off time of the catalyst and at the same time reduce the thermal degradation and ageing of the catalyst to the minimum possible extent by adopting an approach with Dynamic Catalytic Converter System (DCCS). The emission tests were conducted at the cold start of a 4 cylinder spark ignition engine with DCCS at different positions of the catalyst at no load conditions.
2017-09-23
Technical Paper
2017-01-1951
Lingfei Wu, Hongshan Zha, Caijing Xiu, Qiaojun He
Abstract Local path planning for obstacle avoidance is one of the core topics of intelligent vehicle. A novel method based on dubins curve and tentacle algorithm is proposed in this article, with the consideration of obstacle avoidance and vehicle motion constraints. First, the preview distance of the vehicle is given according to the current speed, so that the preview point can be found with the information of global path. Then dubins curve is adopted to find a path with appropriate turning radius, between the current position and preview point, satisfying the constraints of current direction and target direction, considering handling and ride comfort of the vehicle. In order to avoid obstacle, tentacle algorithm is adopted. 20 tentacle points are given by moving the original preview point, and then 21 local paths can be given by using dubins curve. Cost function is used to find out the best option of the 21 paths.
2017-09-23
Technical Paper
2017-01-1952
ChengJun Ma, Fang Li, Chenglin Liao, Lifang Wang
Abstract With the load of urban traffic system becomes more serious, the Automatic Parking System (APS) plays an important role in alleviating the burden of drivers and improving vehicle safety. The APS is consisted of environmental perception, path planning and path following. The path following controls the lateral movement of vehicle during the parking process, and requires the trajectory tracking error to be as small as possible. At present, some control algorithms are used including PID control, pure pursuit control, etc. However, these algorithms relying heavily on parameters and environment, have some problems such as slow response and low precision. To solve this problem, a path following control method based on Model Predictive Control (MPC) algorithm is proposed in this paper. Firstly, Kinematic vehicle model and path tracker based on MPC algorithm are built. Secondly, a test bench that composed of CANoe hardware in the loop (HIL) system and steering wheel system is built.
2017-09-23
Technical Paper
2017-01-1954
Peng Hang, Xinbo Chen, Fengmei Luo
Abstract Path tracking is the rudimentary capability and primary task for autonomous ground vehicles (AGVs). In this paper, a novel four-wheel-independent-steering (4WIS) and four-wheel-independent-drive (4WID) electric vehicle (EV) is proposed which is equipped with steer-by-wire (SBW) system. For path-tracking controller design, the nonlinear vehicle model with 2 degrees of freedom (DOF) is built utilizing the nonlinear Dugoff tire model. The nonlinear dynamic model of SBW system is conducted as well considering the external disturbances. As to the path-tracking controller design, an integrated four-wheel steering (4WS) and direct yaw-moment control (DYC) system is designed based on the model predictive control (MPC) algorithm to track the target path described by desired yaw angle and lateral displacement. Then, the fast terminal sliding mode controller (FTSMC) is proposed for the SBW system to suppress disturbances.
2017-09-23
Technical Paper
2017-01-1971
Sihan Chen, Libo Huang, Xin Bi, Jie Bai
Abstract For sensing system, the trustworthiness of the variant sensors is the crucial point when dealing with advanced driving assistant system application. In this paper, an approach to a hybrid camera-radar application of vehicle tracking is presented, able to meet the requirement of such demand. Most of the time, different types of commercial sensors available nowadays specialize in different situations, such as the ability of offering a wealth of detailed information about the scene for the camera or the powerful resistance to the severe weather for the millimeter-wave (MMW) radar. The detection and tracking in different sensors are usually independent. Thus, the work here that combines the variant information provided by different sensors is indispensable and worthwhile. For the real-time requirement of merging the measurement of automotive MMW radar in high speed, this paper first proposes a fast vehicle tracking algorithm based on image perceptual hash encoding.
2017-09-23
Technical Paper
2017-01-1989
Yi Chen, Gaoxiang Lin, Ying He
Abstract Chinese National projects “13th Five Year Plan” and “Made in China 2025” have both put forward a goal of developing Intelligent and Connected Vehicles(ICV). Shanghai is a typical city of automobile industry which spearhead the development of China’s ICV industry. After the adjustment and transition of industrial structure, Shanghai has initially formed the industrialization layout of ICV covering core areas including environmental perception, intelligent decision-making, actuator, human-computer interaction and vehicle integration. However, currently Shanghai is still in the beginning stage and there exists a large gap with world advanced level in both the core technology and marketization. This article is based on former qualitative survey combined with quantitative analysis which uses the Analytic Hierarchy Process(AHP) method to objectively evaluate the status quo and development trend of Shanghai’s ICV.
2017-09-23
Technical Paper
2017-01-2010
Junfeng Yang, Michael Ward, Jahangir Akhtar‎
Abstract The Connected and Autonomous Vehicles (CAVs) promise huge economic, social and environmental benefits. The autonomous vehicles supposed to be safer than human drivers. However, the advanced systems and complex levels of automation could also bring accidents by tiny faults of hardware or errors of software. To achieve complete safety, a safety case providing guidance on the identification and classification of hazardous events, and the minimization of these risks needs to be developed throughout the entire development lifecycle process of CAVs. A comprehensible and valid safety case has to employ appropriate safety approaches complying with the automotive functional safety requirements in ISO 26262.
2017-09-23
Technical Paper
2017-01-2005
Zhihong Wu, Jian_ning Zhao, Yuan Zhu, Qingchen Li
Abstract Vehicle cybersecurity consists of internal security and external security. Dedicated security hardware will play an important role in car’s internal and external security communication. TPM (Trusted Platform Module) can serve as the security cornerstone when vehicle connects with external entity or constructs a trusted computing environment. Based on functions such as the storage of certificate, key derivation and integrity testing, we research the principle of how to construct a trusted environment in a vehicle which has telematics unit. HSM (Hardware Security Module) can help to realize the onboard cryptographic communication securely and quickly so as to protect data. For certain AURIX MCU consisting of HSM, the experiment result shows that cheaper 32-bit HSM’s AES calculating speed is 25 times of 32-bit main controller, so HSM is an effective choice to realize cybersecurity.
2017-09-23
Technical Paper
2017-01-2007
Fang Li, Lifang Wang, Yan Wu
Abstract With the rapid development of vehicle intelligent and networking technology, the IT security of automotive systems becomes an important area of research. In addition to the basic vehicle control, intelligent advanced driver assistance systems, infotainment systems will all exchange data with in-vehicle network. Unfortunately, current communication network protocols, including Controller Area Network (CAN), FlexRay, MOST, and LIN have no security services, such as authentication or encryption, etc. Therefore, the vehicle are unprotected against malicious attacks. Since CAN bus is actually the most widely used field bus for in-vehicle communications in current automobiles, the security aspects of CAN bus is focused on. Based on the analysis of the current research status of CAN bus network security, this paper summarizes the CAN bus potential security vulnerabilities and the attack means.
2017-09-23
Technical Paper
2017-01-2011
Suyash Singh, Ankur Mathur, Sandeep Das, Purnendu Sinha, Vinay Singh
Abstract In the Smart Cities, main objective is to promote cities that provide core infrastructure and give a decent quality of life to its citizens, a clean and sustainable environment and application of ‘Smart’ Solutions. The process said for utilization of available resources is the best fit for our concept. Our concept is to convert and refurbish the old and scrap vehicles which will increase their longevity and can be used in any smart city in India or abroad. The ultimate aim to provide this technology for the development of any new smart city in India is the utilization of available resources and reduction in the junk materials and environmental pollution. Refurbishing the old and scrap vehicles with replacement of IC engines doesn’t mean that they will be kept as a scrap and be thrown away, our idea is to utilize maximum of all the available resources. The IC engines taken out of these vehicles will be re-used appropriately.
2017-09-23
Technical Paper
2017-01-1973
Yang Yin, Xin Bi, Libo Huang, Shitao Yan
Abstract Millimeter wave (MMW) automotive radar plays an important role in the advanced driving assistance system (ADAS), which detects vehicles, pedestrians and other obstacles. In the adaptive cruise control (ACC) and the automatic emergency brake (AEB) system, the target needs to be oriented. One of the automotive radar’s task is to get the direction information which includes the range, speed, azimuth and height of the target by high intermediate frequency (IF) signal sampling rate. In order to solve the problem of high sampling rate for the MMW radar caused by the traditional Nyquist sampling theorem when the target is located, a new method based on the compressed sensing (CS) for the target location is proposed in this paper. This paper presents the linear frequency modulated continuous wave (LFMCW) model and simulates the sampling and reconstruction of the radar’s IF signal via CS technique by using MATLAB.
2017-09-23
Technical Paper
2017-01-1982
Xiaoming Lan, Hui Chen, Xiaolin He, Jiachen Chen, Yosuke Nishimura, Kazuya Ando, Kei Kitahara
Abstract In the recent years, the interaction between human driver and Advanced Driver Assistance System (ADAS) has gradually aroused people’s concern. As a result, the concept of personalized ADAS is being put forward. As an important system of ADAS, Lane Keeping Assistance System (LKAS) also attracts great attention. To achieve personalized LKAS, driver lane keeping characteristic (DLKC) indices which could distinguish different driver lane keeping behavior should be researched. However, there are few researches on DLKC indices for personalized LKAS. Although there are many researches on modeling driver steering behavior, these researches are not sufficient to obtain DLKC indices. One reason is that most of researches are for double lane change behavior which is different from driver lane keeping behavior.
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