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Viewing 151 to 180 of 86934
2018-04-03
Technical Paper
2018-01-0036
Yu Takeuchi, Tanaka Hideyuki, Hitosugi Kazuo, Uno Tomoki
Currently, development of vehicle control system targeting Full Driving Automation (Autonomous driving level 5) has been advanced. Then, some applications of autonomous driving system likes Lane keeping Assist system (LKA) and Auto Lane Change system (ALC) are put on the market (Autonomous driving level 1-3). However, the conventional system using information from front camera, it is difficult to operate in some situations. We propose autonomous driving system using high accuracy vehicle position estimation technology and high definition map. LKA system calculates target steering wheel angle based on both of vehicle position information from the Global Navigation Satellite System (GNSS) and target lane of high definition map, according to the method of front gaze driver model. Then, the system controls steering wheel angle by Electric Power Steering (EPS). In the case of ALC, a target path of lane-change is generated based on information of own lane and next one.
2018-04-03
Technical Paper
2018-01-0037
Tsung-Ming Hsu, Wei-Jen Wang
Intersections and road junctions are with higher traffic accidents due to the wrong decisions of human drivers. In this paper, we consider an artificial intelligence method to mimic decisions of human drivers for highly automated vehicles at passing an urban intersection. We applied the Principal Component Analysis and uniformly scaling for the Support Vector Machine learning is applied to model time series features. The effect due to misspecification by ignoring time series issue is investigated through the comparison of predicted action accurate rate is investigated by a simulation study on the software PreScan. Keywords: Intersections, Artificial intelligence, Principal Component Analysis, Uniformly scaling, Support Vector Machine, Time series.
2018-04-03
Technical Paper
2018-01-0042
William Buller, Helen Kourous, Jakob Hoellerbauer
One of the principal bottlenecks for sensing and perception algorithm development for autonomous vehicles is the ability to evaluate tracking algorithms against ground truth data. By ground truth we mean independent knowledge of the position, size, speed, heading, and class of objects of interest (moving and stationary) in complex operational environments. Our goal was to execute a data collection campaign at an urban test track in which trajectories of moving objects of interest are measured with auxiliary instrumentation, in conjunction with several AVs with a full sensor suite of radar, LiDAR, and cameras. Multiple autonomous vehicles (both moving and stationary) collected measurements in a variety of scenarios designed to incorporate real world interactions of vehicles with bicyclists and pedestrians. Trajectory data for a set of bicyclists and pedestrians was collected by separate means.
2018-04-03
Technical Paper
2018-01-0043
Arvind Jayaraman, Nathan Kurtz
In the world of automated driving, sensing accuracy is of course of the utmost importance, and proving that your sensors can do the job is serious business. This is where ground-truth labeling has an important role in Autoliv’s validation process. Currently annotating ground-truth data is a tedious manual effort, involving finding the important events of interest and using the human eye to determine objects from LiDAR point cloud images. We present a tool we developed in MATLAB to alleviate some of the pains associated with labeling point-cloud data from a LiDAR sensor and the advantages that tool provides to the labeler. We discuss the capabilities of the tool to assist users in visualizing, navigating and annotating objects in point-cloud data, tracking these objects through time over multiple frames and then using the labeled data for developing machine-learning based classifiers.
2018-04-03
Technical Paper
2018-01-0041
Ayush Goel, Somnath Sengupta
Autonomous vehicles at various stages will impact the future of transportation by improving reliability, comfort and safety of the passengers. In this paper, for an existing experimental vehicle, a level-1 autonomous controller is proposed primarily for stop-and-go scenarios along with the additional functionalities of automatic cruise control (ACC) and automatic emergency braking (AEB). Since the rigorous testing of autonomous vehicle in actual roads can be time consuming, costly and having safety issues, a simulation test-bench based approach is considered to develop and test the controller. Based on practical data from ultrasonic sensors, camera, throttle and brake signals, a controller is developed in simulation environment to primarily maintain a safe distance from surrounding traffic objects while fulfilling certain requirements such as jerk levels, conditional braking, speed limits, etc.
2018-04-03
Technical Paper
2018-01-0047
Yucheng Liu
A data acquisition system along with a sensor package was designed and installed on an existing mechanically-controlled cargo tractor to gather more data on their usage patterns. The data collected through the developed system include GPS route, vehicle speed and acceleration, engine state, transmission state, seat occupancy, fuel level, and video recording. The sensor package was designed and integrated in a way that does not interfere with the driver’s operation of the cargo tractor. Cellular network connectivity was employed to retrieve sensor data so as to minimize human effort and maintain typical usage patterns of the outfitted cargo tractors. Testing and validation results showed that the developed system can correctly and effectively record data necessary for further analysis and optimization. A fuel usage analysis was then completed using a chassis dynamometer based on the collected data.
2018-04-03
Technical Paper
2018-01-0044
Toshiki KINDO, Bunyo Okumura
The collision avoidance capability of automated vehicles consists of response capability and preparation capability. A collision occurs when the a-th vehicle's path and the b-th vehicle path have a crossing point and the two vehicles drive on the crossing point at same time. To describe the above conditions, we introduce candidate path matrix R_{an} representing the a-th vehicle's path with dense way-points referred by n and conflict tensor C_{an,bm} representing whether there is enough arrival time interval to avoid collision with the b-th vehicle or not. Then the collision avoidance equation of the automated vehicle a is given by a following equation in terms of R_{an} and its speed v_a, Σ_{nm} R_{an} C_{an,bm}(v_a,v_b) R^n_{bm}= 0 where the b-th vehicle condidate matrix R^n_{bm} and its speed v_b are evaluated with "normal driving" model. On the concise representation, we consider a behavioral hazard describing the candidate path matrix change from R^n_{bm} to R^h_{bm}.
2018-04-03
Technical Paper
2018-01-0045
Sudripto De
Ford Motor’s Allan Mullaly said in a Consumer Electronics Show in Las Vegas “we are a car company, but we are learning how to think like an electronics company”. As mobile data traffic expands 10-fold from 30 Exabytes to 292 Exabytes in 2019, and the total mobile services subscription reaches 6.8 billion, in a global population of 7.3 billion, there is a compelling move towards connected cars and services. Though SDB research suggests US$ 18 billion additional revenue from these services, but most important question is “Are the consumers, who buy cars, willing to pay extra for these services”. Traditional business models of OEMs buys parts from Tier-1 suppliers, and selling the vehicles to consumers as a one-time sales revenue per consumer, is not the successful model. Telematics services, introduced in early 2000, bears testimony. For the New Business Models, the OEMs have to work with the ecosystem of service providers, who themselves have different business model.
2018-04-03
Technical Paper
2018-01-0051
Satvik Jain, Rahul Fageria
Turboexpansion is a concept which is aimed at reducing the fuel consumption of pressure-charged combustion engines by providing over-cooled air to the engine prior to its induction in the combustion chamber. The performance of the engine is dependent on intake charge density which is preferred to be high at reduced charge air temperature. This becomes achievable through a cooling system known as a turbo expander which expands a high-pressure gas to produce work that is usually employed to drive a compressor. Though, initially used for the purpose of refrigeration in industries, for the past few decades various researches have proved its efficiency in internal combustion engines. In gasoline engines, it is usually employed to extend the knock limit and reduce carbon emissions. Also, an extension to the knock limit allows several improvements in parameters such as increased specific output, an increase in compression ratio and a reduction in the fuel consumption of the engine.
2018-04-03
Technical Paper
2018-01-0050
Zhijia Yang, Richard Stobart
Thermoelectric generator has very quickly become a hot research topic in the last five years because its broad application area and very attractive features such as no movable parts, low maintenance, variety of thermoelectric materials that total together cover a wide temperature range. The biggest disadvantage of thermoelectric generator is its low conversion efficiency. So that when design and manufacture a thermoelectric generator for exhaust waste heat recovery from an automotive engine, the benefit of fuel consumption from applying a thermoelectric generator would be very sensitive to the weight, the dimensions, the cost and the practical conversion efficiency. Additionally, the exhaust gas conditions vary with the change of engine operating point which creates a big challenge for the design of the hot side heat exchanger in terms of optimizing the electrical output of the thermoelectric generator during an engine transient cycle.
2018-04-03
Technical Paper
2018-01-0049
Ge-Qun Shu, Nanhua Yan, Mingru Zhao, Linqing Li
Transcritical Rankine cycle (TRC) is a promising technology for the engine waste heat recovery due to its good temperature matching ability for the waste heat sources from engines. Since CO2 and small molecule hydrocarbons have good chemical stability and thermal performance, their mixtures are the potential working fluids for the engine waste heat recovery. Besides, CO2 can be used as the retardant to suppress the flammability of hydrocarbons to ensure safety. In this research, zeotropic mixtures of CO2 blends with five small molecule hydrocarbons as the working fluids of TRC are studied. A thermodynamic model of TRC system is established to evaluate the thermal performance of those mixtures, the effects of mass fraction of CO2, turbine inlet temperature and pressure are investigated. The influence of composition shift of the zeotropic mixtures during condensation is also discussed.
2018-04-03
Technical Paper
2018-01-0048
Takeshi Sakuma, Tatsuo Kawaguchi, Daisuke Kimura, Makoto Yoshihara, Teijiro Takahashi, Hitoshi Mizuno
Exhaust heat recovery (EHR) system is attracting much attention as an effective means of improving fuel economy, especially at a low ambient temperature. Reducing the weight (heat mass) of EHR system is important for effective warm-up the engine at cold start, because recovered heat energy from exhaust gas is consumed to warm up the system itself. In this paper, we propose a new concept EHR system which applies a highly heat-conductive SiC honeycomb with thermal conductivity of 150W/mK, and also present vehicle testing results of two prototypes compared to the metal (stainless steel, 20W/mK) heat exchanger system on the market. SiC_prototype-1 adopted coaxial-bypass design with weight of 1kg, and steady-state heat recovery efficiency of 55% (at 36kg/h).
2018-04-03
Technical Paper
2018-01-0058
Ge-Qun Shu, Daiqiang Li, Guopeng Yu, Guangdai Huang
The supercritical CO2 power cycle system for waste heat recovery (WHR) of internal combustion engine (ICE) has widely been concerned as a research hotspot. And the expander is a key component in the supercritical CO2 power system. Rolling rotor expander has the following advantages: compact size, light weight, less moving parts, high stability and long service life, which qualify it a very suitable choice for engine’s waste heat recovery system. For a self-designed rolling rotor expander using supercritical CO2 as its working fluid, FLUENT software was used to simulate its internal flow field in this study, obtaining the changes of the internal pressure field and turbulent kinetic energy. The causes of local vortex in the expansion process were analyzed. Under different working conditions of the expander, the change of internal pressure and the distribution of P-V curve were observed, and the work capacity under different inlet pressure was analyzed.
2018-04-03
Technical Paper
2018-01-0054
James Szybist, Steven Davis, John Thomas, Brian C. Kaul
Thermoelectric generators (TEGs) have been researched and developed for harvesting energy from otherwise wasted heat. For automotive applications this will most likely involve using internal combustion engine exhaust after the catalyst system as the heat source, although applications to exhaust gas recirculation systems and compressed air coolers have been suggested. A thermoelectric generator based on half-Heusler thermoelectric materials was developed, engineered and fabricated, targeting a gasoline passenger sedan application. This generator was installed on a gasoline engine exhaust system in a dynamometer cell, and positioned immediately downstream of the close-coupled three way catalyst. The generator was characterized at over a matrix of steady-state conditions representing the important portions of the engine map, and also at selected transient conditions. Detailed performance results are presented.
2018-04-03
Technical Paper
2018-01-0059
Masahiro Morishita, Toshiya Uchida, Gursaran D. Mathur, Takenao Kato, Kazuhiko Matsunaga
Masahiro Morishita & Toshiya Uchida, CalsonicKansei Japan Gursaran D. Mathur*, CalsonicKansei North America Kazuhiko Matsunaga, Isuzu Motors Inc, Japan In recent years, a number of OEMs have started using idle start stop function to save energy and to reduce pollution. For vehicles with internal combustion engines the engine stops at a red light or a stop sign when the vehicles comes to a rest. At this time the compressor of the AC loop also stops. Blower fan remains operating at idle condition and the air temperature at the vent outlets increases. This cause discomfort to the occupants sitting within the vehicle cabin. In these this situation, engine needs to start idling to run AC system to provide comfort to occupants by spending fuel. For idle start stop technology, it is necessary to design a highly efficient system. To develop a highly efficient idle start stop system, idling time needs to be minimized.
2018-04-03
Technical Paper
2018-01-0057
Alberto Carriero, Matteo Locatelli, Kesavan Ramakrishnan, Giampiero Mastinu, Massimiliano Gobbi
The paper reviews the state of the art of cooling systems employed in electric traction motors. In recent years, the pursuit of sustainable and ecofriendly mobility solutions has pushed the research towards the development of electric vehicle powertrains. Permanent magnet electric machines are preferred over the other possible motors due to high efficiency and torque density. However, the performance of PM machines is deteriorated at high temperatures since the magnet remanence reduces with increasing temperature until a maximum allowable point, above which demagnetization occurs. Moreover, the reduction of remanence requires higher electric current to produce the demanded output torque which increases the winding loss significantly. The temperature rise of stator winding increases its DC resistance as well. In order to mitigate these problems, different solutions for the thermal problem have been researched and adopted, each one with its own pros and cons.
2018-04-03
Technical Paper
2018-01-0063
Dandong Wang, Tianyuan Gao, Wanyong Li, Yun Yang, Jun-ye Shi, Jiangping chen
Automobile heat pump technology is an effective method to save energy consumption and extend driving ranges in cold weather for electrical vehicles. Due to the reverse thermal cycle and changed operation conditions, automobile heat pump cycle characteristics are different from conventional air conditioning system. This paper presents KULI-based models to simulate steady-state operation of both direct expansion (DX) and secondary loop (SL) automobile heat pump systems using HFC-R134A or HFO-R1234yf refrigerant. The DX model includes a compressor, an indoor condenser, an expansion device and an outdoor evaporator. The condenser in DX model is replaced by a secondary coolant loop in SL model, which consists of a coolant plate type heat exchanger, an electrical pump and a coolant to air heat exchanger. The developed R134A DX and SL models were verified against steady-state experimental data.
2018-04-03
Technical Paper
2018-01-0055
Gursaran D. Mathur
In last few years, the author has conducted a number of experimental studies with refrigerant HFO-1234yf. In these experimental studies, the author has experimentally determined overall system performance with and without suction line heat exchanger; TXV optimization; both evaporator and condenser thermal and hydrodynamic performances; and heat transfer coefficients for both two-phase flow boiling and condensation of HFO-1234yf for typical automotive heat exchangers and AC loop configurations. In some of the studies by the author, the experimentally measured heat transfer coefficients for flow boiling and condensation were compared to the predictions from standard correlations available in the literature. The experimentally measured magnitudes of the heat transfer coefficients were within ±12~20% of the predicted numbers. However, these correlations were not specifically developed for HFO-1234yf refrigerant.
2018-04-03
Technical Paper
2018-01-0060
Jingwei Zhu, Stefan Elbel
Expansion work recovery by two-phase ejector is known to be beneficial to vapor compression cycle performance. However, one of the biggest challenges with ejector vapor compression cycles is that the ejector cycle performance is sensitive to working condition changes which are common in automotive applications. Different working conditions require different ejector geometries to achieve maximum performance. Slightly different geometries may result in substantially different COPs under the same conditions. The ejector motive nozzle throat diameter (motive nozzle restrictiveness) is one of the key parameters that can significantly affect ejector cycle COP. This paper presents the experimental results of the application of a new two-phase nozzle restrictiveness control mechanism to an automotive transcritical R744 ejector cycle.
2018-04-03
Technical Paper
2018-01-1393
Eitaro Koya, Masahiko Nakagawa, Shinya Kitagawa, Jun Ishimoto, Yoshikatsu Nakano, Naoya Ochiai
The authors have found that it is effective to generate an atomized state of molten metal, when filling it to a cavity, to improve the strength of the products manufactured by HPDC. In the experiments so far, the atomization state during filling of aluminum molten metal has been observed by spraying it into open space. However, with this method, it is not possible to clarify the behaviors of the molten aluminum injected into a cavity. Accordingly, we tried to clarify the state in the cavity by simulation. There has been no study where the filling condition of molten aluminum in HPDC is calculated in detail. Consequently, the calculation method was developed by applying LES (Large Eddy Simulation). In LES, it is possible to perform a large-scale calculation while using a fine mesh, so it is possible to simulate in detail the state of the tip portion of the injected molten metal.
2018-04-03
Technical Paper
2018-01-1398
Penglei Fu, Baoxiang Qiu, Chao Ding, Bomei Shi, Yunqing Zhang
The optimal design of vehicle NVH performance plays an important role in Vehicle research and development. However, the unbalance of propeller shaft has a great influence on the vehicle NVH performance. Analysis of unbalanced propeller shaft concentrates mainly on single propeller shaft at present. But, the distance of gearbox and final drive is relatively far in heavy truck, and the power is transmitted by multiple propeller shafts, so the coupling phenomenon of the unbalance on single propeller shaft will occurs. Coupling phenomenon of unbalance could worsen vehicle NVH performance. The main cause of vehicle NVH performance and the forces on propeller shaft support bearing was analyzed in this paper, such as the characteristics of multiple propeller shafts arrangement, phase angle of propeller shafts and the location and phase of unbalance. A rigid-flexible coupled model of three propeller shafts was set up.
2018-04-03
Technical Paper
2018-01-1397
Fulun Yang, Kieran Hess, Larry Geer
Bushing such as converter inlet and outlet, muffler inlet and outlet is one of most important components of exhaust system. Durability performance of bushing fatigue impacts durability of exhaust system directly. One effective method to predict bushing fatigue life accurately is very critical to optimize bushing design, and to reduce bushing fatigue life validation cycle and cost. It is well known that fatigue is not deterministic phenomenon but statistical phenomenon. Prediction of reliability of bushing fatigue life makes more sense for bushing fatigue life validation and verification. In this study, different methods such as traditional stress analysis method and Verity method are used to predict busing fatigue life. Both parent material and weld failures are considered. Prediction results by different method are compared to correlate test results. Weibull distribution is used to calculate reliability of bushing fatigue life.
2018-04-03
Technical Paper
2018-01-1404
Avik Banerjee, Pankaj Mallick, Ankit Mitra
This study presents a comparative analysis of seat and suspension parameters on a system level to achieve optimum ride comfort for the occupant. A lumped-parameter full-vehicle ride model with five occupants is used and a low amplitude pulse signal is provided as the road disturbance input. The peak vertical displacement and acceleration of the occupant’s head are used as measures of ride comfort. Using a design of experiments approach, the most critical seat cushion, seat structure and suspension parameters and their interactions affecting the ride comfort are determined. An optimum combination of parameters to achieve minimum peak vertical displacement of the occupant’s head is identified using a response surface methodology.
2018-04-03
Technical Paper
2018-01-1403
Hui Pang, Junjie Yang, Jun Liang, Zeren xu
This paper aims to present a novel variable rate reaching law (VRRL) control scheme for vehicle semi-active suspension system, which can reduce the chattering phenomena in high frequency compared with the traditional exponent reaching law (TERL) sliding-mode controller. First, an ideal-skyhook damping suspension system is taken as the reference objective to be followed. Then, this control scheme is combined with the fuzzy logic control (FLC) to change the sliding mode reaching rate dynamically with consideration of the sliding-mode reaching segment characteristics in the close-loop control system, and further to achieve the chattering suppression. Afterwards, the simulation analysis is conducted under the random road and bump road surface, respectively, and the results verify the effectiveness and feasibility of the proposed enhanced fuzzy sliding-mode controller.
2018-04-03
Technical Paper
2018-01-1402
H. El-taweel, Mohamed M. Abd elhafiz, H. Metered
A fuzzy-PID controller is designed for a half vehicle active suspension system. The optimal values of controller parameters for minimizing the objective function are tuned using Genetic Algorithm (GA). A mathematical half-vehicle model of five degrees of freedom suspension system is derived and simulated using Matlab/Simulink software. Bump and random road excitations are used to evaluate the performance of the proposed controller. The performance of the active suspension with fuzzy-PID controller is compared with passive suspension system to show the efficiency of the proposed active suspension. The simulation results show that the active suspension system controlled using the fuzzy-PID controller can offer significant improvements of ride comfort and vehicle stability.
2018-04-03
Technical Paper
2018-01-1401
Xinxin Shao, Fazel Naghdy, Haiping Du
Active suspension control for in-wheel SRM driven electric vehicle is proposed to improve the vehicle ride comfort and motor performance. The mounting of the electric drives on the wheels, known as in-wheel motor (IWM), has attracted increasing research interests in recent years due to its inherent merits. However, The IWMs directly attach to the wheels that can result in an increase in the unsprung mass of the vehicle and a significant drop in the suspension ride comfort performance and road holding stability. Structures with suspended shaftless direct-drive motors have the potential to improve the road holding capability and ride performance. The quarter car model equipped with SRM is established, in which the stator is served as a dynamic vibration absorber.
2018-04-03
Technical Paper
2018-01-1408
HeonJoon Park, SungChul Cha, SeHeon Kim
The aim of this work is to investigate the current expensive heat treatment “Kolsterizing” and subsequently to develop new modified inexpensive heat treatment with increase of material properties. Considered parts are stopper (SUS303) and position ring (1.4305) of high pressure injector in powertrain. With development of new modified heat treatment the supply chain shall be multiple and therefore stable. At first current Kolsterizing is investigated and resulted: hardness (HV50) 804-913, layer thickness of 16,1-21,52 ㎛, corrosion resistance was maximum 1 hour at 8.25% NaCl solution. New modified heat treatment is Super Saturated NitroCarburizing (SSNC) which is generated with nitrogen and carbon sourcing gas in temperature range of 350-450 ℃. The process in detail is: nitrogen purging and heating, activation at 360℃ for 1 hour, heating, nitrocarburizing at 350-450℃ for 4-48 hours, cooling. At the subsurface carbon rich S-phase is formed and at surface nitogen rich S-phase is formed.
2018-04-03
Technical Paper
2018-01-1407
Yoel Emun, Guangchun Quan, Joseph Kish, Hatem Zurob
The purpose of this project is to perform a comparative study on corrosion resistant behaviour of stainless steels currently used in industry. The three corrosion mechanisms commonly occurring in the exhaust system include high temperature oxidation, acid condensate corrosion and sensitization induced intergranular corrosion. To compare the materials thoroughly, high temperature oxidation testing, acid condensate testing and potentiodynamic testing was conducted. From these tests pitting densities from the acid condensate tests, double loop polarization curves from potentiodynamic testing and mass losses and gains from high temperature oxidation testing has been acquired. A ranking system was then put in place to incorporate the materials performance across all three tests to rank them accordingly.
2018-04-03
Technical Paper
2018-01-1406
Eric Randolph, Florent Bocher, Svitlana Kroll, Nolan Wright, Graham Conway, Craig Gibson
The objectives of this project were to investigate the corrosion potential of condensate in a stoichiometric spark-ignited (SI) engine when running exhaust gas recirculation (EGR) and determine the effects of fuel sulfur on corrosion. A 2.0 L turbocharged direct-injected SI engine was operated with low-pressure EGR for this study. The engine was instrumented for visual, thermodynamic and electrochemical analyses to determine the corrosion potential at locations where condensation was deemed likely in an EGR engine. The electrochemical analysis was performed using multi-electrode array corrosion probes. Condensate was also collected and analyzed. These analyses were performed downstream of both the charge air cooler and the EGR cooler. It was found that while conditions existed for sulfuric acid to form with high sulfur fuel, no sulfuric acid was detected by any of the measurement methods.
2018-04-03
Technical Paper
2018-01-1405
Kaiyan Wang
This paper starts with study on the transfer characteristics, and the vibration isolation of the cab suspension.The multi-body dynamic model of the vehicle was built in order to analyze the response of the cab suspension. This model includes the cab and its suspension, the power train and its mount, the frame, the suspension, the vehicle-bridge, the steering system and the tires, etc. Design of experiments method was taken to quantitatively analyze the impacts of changing cab suspension parameters.The piecewise function method was used in fitting the characteristic of the air spring. The vibration transmissibility was chosen as optimization objective.The genetic algorithm was used as the optimization method. The analysis results show that there only limited effectiveness on coil spring. So the improvement plans were proposed to replace the coil spring with an air spring and setting transverse damper. According to the plans, the original cab suspension was modified.
Viewing 151 to 180 of 86934