Criteria

Text:
Sector:
Display:

Results

Viewing 121 to 150 of 86934
2018-04-03
Technical Paper
2018-01-0018
Qiang Hu, Feng Luo
In the automotive network architecture, the basic functions of gateway include routing, diagnostic, network management and so on. With the rapid development of connected vehicles, the cyber security has become an important topic in automotive network. A spoof ECU can be used to hack the automotive network. In order to prevent the in-vehicle networks from attacking, automotive gateway is an important part of the security architecture. A secure gateway should be able to authenticate the connected ECU and control the access to critical network domain. The data and signals transferred between gateway and ECU should be protected to against wiretap attacking. The purpose of this paper is to design a secure gateway for in-vehicle networks. In this paper, the designing process of automotive secure gateway is presented. Based on the threat analysis, security requirements for automotive gateway are defined.
2018-04-03
Technical Paper
2018-01-0031
Nazmuzzaman khan, Gregory Medlock, Scott Graves, Sohel Anwar
In this paper, the design, implantation, and testing of an autonomous agricultural robot with GPS guidance is presented. This robot is also responsible for weed detection and killing by spraying appropriate herbicide as well as fertilizing. This rover is powered by 5 12V electric bike batteries and two electric motors. Machine learning algorithms such as Haar Cascade has been successfully utilized to detect three kind of common weeds found in a corn field. The robot control system consists of GPS guided control of propulsion system and steering actuators, an image processing and detection system, and an spray control system for herbicide and fertilizer applications. Multiple microprocessors such as Raspberry Pi 3, Arduino, as well as an on-board computer have used to provide all control functions in an integrated fashion. Open sources software such as Mission Planner and ReachView have been used to provide autonomous guidance of the vehicle.
2018-04-03
Technical Paper
2018-01-0030
Yifan Ye, Jian Zhao, Jian Wu, Weiwen Deng
When the vehicles are at the threat of collisions, steering usually needs shorter longitudinal distance than braking for collision avoidance, especially under the condition of high speed or low adhesion. Thus, more collision accidents can be avoided in the same situation. The steering assistance is in need since the operation is hard for drivers. And considering the dynamic characteristics of vehicles in those maneuvers, the real-time and the accuracy of the assisted algorithms is essential. In view of the above problems, this paper first takes lateral acceleration of the vehicle as the constraint, aiming at the collision avoidance situation of the straight lane and the stable driving inside the curve, and trajectory of the collision avoidance is derived by a quintic polynomial.
2018-04-03
Technical Paper
2018-01-0024
Igor V. Gritsuk, Dmytro Klets PhD, Vasyl Mateichyk PhD, Miroslaw Smieszek PhD
Remote monitoring is the most important stage in controlling the technical condition of a modern vehicle in operation conditions. Remote control of the technical condition involves using of V2I systems in order to form and apply individual maintenance and repair systems. Developed in the article V2I information model is characterized by the presence of the vehicles digital space, limited by regulatory rules, with means for technical condition parameters monitoring and components of infrastructure for each vehicle monitoring. The article describes the features of the V2I information system and the process of monitoring and evaluation the vehicle technical condition in operating conditions, with the possibility of forecasting. The monitoring information system is designed to ensure the vehicles efficient operation in non-stationary operating conditions, with continuous consideration of information from road and transport infrastructure.
2018-04-03
Technical Paper
2018-01-0026
Hothaifa Al-Qassab, Mohammed Al-Qizwini, Hayder Radha, Su Pang
The development of connected-vehicle technology, which includes vehicle-vehicle and vehicle-infrastructure communications, opens the door for unprecedented active safety and driver-enhanced systems. In addition to exchanging basic traffic messages among vehicles for safety applications, a significantly higher level of safety can be achieved when vehicles and designated infrastructure-locations share their sensor data. In this paper, we propose a new system where cameras installed on multiple vehicles and infrastructure-locations share and fuse their visual data and detected objects in real-time. The transmission of camera data and/or detected objects (e.g., pedestrians, vehicles, cyclists, etc.) can be accomplished by many communication methods. In particular, such communications can be accomplished using the emerging Dedicated Short-Range Communications (DSRC) technology.
2018-04-03
Technical Paper
2018-01-0064
Takuya Kubota, Takayuki Ishilkawa, Jun Tosaka, Hidetoshi Okayasu
This paper describes newly developed model-in-the-loop simulation (MILS) which makes design for cooperative climate control logics between automotive HVAC (heating, ventilation and air conditioner) and auxiliary thermal devices more efficient in considering thermal sensation and comfort of occupants. The auxiliary thermal devices such as an air-conditioned seat and a heated steering wheel consume less energy than the HVAC, and they have a potential to improve the total energy consumption satisfying thermal comfort of occupants. However, it is not easy to design the cooperative climate control logics for these thermal devices since thermal sensation and comfort must be taken into account while the logic optimization. The proposed MILS consists of thermal-environment model, thermal-device model, ambient conditions and climate control logics. The thermal-environment model simulates dynamics of temperature distribution in a cabin and human body.
2018-04-03
Technical Paper
2018-01-0065
Mark Hepokoski, Allen Curran, Timothy Viola, Niklas Lindedal, Ronnie Hansson, Sam Gullman
In a previous study, a passive sensor (HVAC) manikin coupled with a human thermal model was used to predict the thermal comfort of human test participants. The manikin was positioned among the test participants while they were collectively exposed to a mild transient heat up within a thermally asymmetric chamber. Ambient conditions were measured using the HVAC manikins’ distributed sensor system, which measures air velocity, air temperature, radiant heat flux, and relative humidity. These measurements were supplied as input to a human thermal model to predict thermophysiological response and subsequently thermal sensation and comfort. The model predictions were shown to accurately reproduce the group trends and the “time to comfort” at which a transition occurred from a state of thermal discomfort to comfort. In the current study, the effectiveness of using a coupled HVAC manikin-model system to evaluate a vehicle climate control system was investigated.
2018-04-03
Technical Paper
2018-01-0067
Jiu Xu, Pega Hrnjak
Oil management is an important issue of automobile air conditioning system. High oil circulation ratio (OCR) in the vapor compression system is harmful for heat exchanger performance and compressor reliability. Oil separator is commonly used in air conditioning systems to reduce oil circulation ratio. A better design of oil separator can reduce compressor size and improve system performance. In this study, coalescer and impingement separators are visualized and modeled to investigate the impact of refrigerant properties and flow conditions on oil separation efficiency. Re-entrainment phenomenon of the wire mesh and wavy plate is explained based on the force balance of drag force and surface tension. Oil mist flow at the compressor discharge is quantified by video processing method to evaluate the separation efficiency of different separation structures. A single-layer based model is used to predict the separation efficiency of wire mesh and wavy plates.
2018-04-03
Technical Paper
2018-01-0068
Paul Christ, Thomas Sattelmayer
In modern vehicle air conditioning concepts, the temperatures at the outlets of the Heating Ventilation and Air Conditioning (HVAC) unit are controlled by an automatic climate control system. Therefore, costly temperature sensors are located in the outlet cross sections of the HVAC unit. A novel coupled Proper Orthogonal Decomposition (POD) and Flow Resistance Network (FRN) approach is proposed to accurately predict the enthalpy flow rates at the outlets of an HVAC unit for real time model based control. For this purpose, the integral enthalpy flow rates at the outlets, which result from a complex mixing process in the mixing chamber of the HVAC unit, are approximated by a linear combination of orthonormal POD modes. Furthermore, a classical FRN is established to compute the volume flow rate at the outlets. By combining the classical FRN with the POD model, the weighting coefficients for the POD modes can be determined from the volume flow rates estimated by the network model.
2018-04-03
Technical Paper
2018-01-0070
Saravanan Sambandan, Manuel Valencia, Aamir Khawaja
Abstract In today’s automotive industry, the A/C (Air-conditioning) system emerging into a high level of technological growth to provide quick cooling, warm up and maintaining the air quality of the cabin during all-weather conditions. In the HVAC system, TXV (thermal expansion valve) plays vital role by separating the high side to low side of vapor compression refrigeration system. It also regulates the amount of refrigerant flow to the evaporator based on the A/C system load. The HVAC system bench laboratory is used to conduct the test at different system load conditions and outputs from the tests are evaluated during the initial development stage to select the right TXV in terms of capacity and Superheat set point for a given system. This process is critical in the developmental activity, since the selected TXV was used to build the mule cars for initial assessment of the system performance.
2018-04-03
Technical Paper
2018-01-0071
Lili Feng, Predrag Hrnjak
With market share of electric vehicles continue to grow, there is an increasing demand of heat pump for cabin climate control, as it has much higher energy efficiency when compared to electric heating and helps to cut drive range reduction due to heating. However, heating capacity of heat pump system drops significantly when operating at very low ambient temperature, mostly due to their low operating pressure. This paper presents a way to improve low ambient temperature heating performance by using intermediate vapor bypass at the outdoor heat exchanger, which works as an evaporator in heat pump mode. The experimental results show a 35% increase of heating capacity at -20 ̊C ambient with the improved system as compared to the baseline, and heating performance factor also slightly increased when the system is working at higher ambient temperature to reach the same heating capacity as the baseline.
2018-04-03
Technical Paper
2018-01-0074
Gursaran D. Mathur
During summer season people typically drive their vehicles by setting air conditioning system in recirculation mode to maximize cooling. Carbon dioxide exhaled by occupants remains within the cabin during operation in recirculation mode. The concentration of carbon dioxide starts increasing in the cabin. The CO2 that is inhaled by the occupants goes into their blood stream that negatively affects occupant's health. ASHRAE Standard 62 specifies the safe levels of carbon dioxide in conditioned space for humans. The CO2 concentration limit per ASHRAE is 700 ppm over the ambient conditions on a continuous basis. Current global average ambient concentration level of CO2 as of April 2017 (NOAA, 2017) is approximately 407 ppm. Hence, if the CO2 concentration exceeds approximately 1100 ppm inside of a home or a vehicle cabin, then we must introduce outside air into the home or vehicle cabin to reduce the CO2 concentration.
2018-04-03
Technical Paper
2018-01-0073
Somnath Sen
The present paper outlines the selection and numerical modeling of a high performance and efficient blower motor of an automotive HAVC system. In today’s scenario blower motor is present in every car fitted with HVAC system. The selection of a blower motor is very important in terms of delivering right amount of airflow with minimum consumption of electric power. As the power consumption goes up it significantly contributes in indirect GHG emission from a vehicle. The other major factor of a blower motor is that when it rotates it generates some amount of heat which is very detrimental for its life and performance as well. Also the generated heat may lead to increase in temperature of the main stream flow causing reduction in the cabin cooling. The present study describes the step by step methodology of selecting a blower motor suitable for automotive HVAC application. It involves the evaluation of motor characteristics followed by its durability under operating conditions.
2018-04-03
Technical Paper
2018-01-0075
Ernesto B. Abaya, Karl B. Vergel, Edwin N. Quiros, Ricardo G. Sigua, Jose Bienvenido Biona PhD
The instantaneous fuel consumption measurements obtained from the chassis dynamometer tests using the drive cycles for light duty vehicles in Metro Manila was used in the development of speed-acceleration-fuel consumption models. The Shepard’s interpolation method was used in the development of the models. A program C# language was used to execute the interpolation method. The resulting models are represented by speed-acceleration-fuel consumption surface graphs. The surface graph of each test vehicle represents its estimated fuel consumption variation according to its combined instantaneous speed and acceleration. Actual instantaneous speeds from speed data of surveyed vehicles, defining different traffic conditions by average speed, are used to interpolate instantaneous fuel consumption. Fuel economy, in terms of distance travelled (km) per volume of fuel consumed (liter), is computed from the totaled fuel consumption and total distance traversed.
2018-04-03
Technical Paper
2018-01-0076
Lili Feng, Predrag Hrnjak
The demand for mobile heat pump systems increases with the growing popularity of electric vehicles. One big challenge of such systems using low pressure refrigerant is the substantial drop of heating capacity at low ambient temperature conditions, when heat is most needed. The low suction density associated with low operating pressure in the evaporator is the major reason for the capacity drop. In extremely low ambient temperature, compressor speed may need to be regulated in order to prevent suction pressure going below atmospheric pressure, hence further reducing heat pumping capability. Other factors, such as pressure drop, and refrigerant maldistribution also weakens the system. This paper presents detailed and in-depth analysis of the limiting factors on low ambient temperature operation of a mobile heat pump system. Experimental data are taken for ambient temperatures ranging from -20 to 20 ̊C. Analysis of losses are presented with the aid of a simulation model.
2018-04-03
Technical Paper
2018-01-0077
Jingwei Zhu, Francesco Botticella, Stefan Elbel
In this study, the influence of compressor speeds, ejector motive nozzle needle positions and evaporator inlet EEV openings on the OCRs of an automotive R744 transcritical standard ejector cycle was experimentally investigated. Significantly higher OCR (~10%) was observed at the evaporator inlet of the ejector cycle than at the high pressure side, which is due to the large ratio of compressor mass flow rate to oil return flow rate. It has been observed that evaporator OCR was increased with increasing compressor speed. When the motive nozzle needle moved towards the nozzle throat, evaporator OCR was observed to be significantly lowered due to the higher oil separation efficiency of the internal oil separator at lower compressor discharge flow rate and smaller ratio of compressor mass flow rate to oil return flow rate.
2018-04-03
Technical Paper
2018-01-0078
Rahul Fageria, Satvik Jain
Turbochargers have become an inevitable part of modern engines for their ability to improve an engine's efficiency and power output through forced induction using the exhaust gas energy which otherwise would have been wasted. And with their use, there is always some unwanted heat as a by-product. For that, turbo intercoolers are employed, they reduce the temperature of the forced air before reaching the engine and improve their volumetric efficiency by increasing intake air charge density through an isobaric cooling. The forced air produced by the turbocharger is routed through the intercooler where its temperature is reduced before reaching the engine. Intercoolers also eliminate the need for using the wasteful method of lowering intake charge temperature by the injection of excess fuel into the cylinders' air induction chambers, to cool the intake air charge, prior to its flowing into the cylinders.This has made modern heavy duty diesel vehicles far more efficient.
2018-04-03
Technical Paper
2018-01-0079
Rishabh Bahuguna, Tanmay Prasad, Rishabh Khanna, Akshyt Bimal Kumar, K Nantha gopal, Sushant Srivastava, Aagosh Mishra, Ashok B
In Formula Student, the vehicle working parameters are quite disparate from that of a commercially designed vehicle. The inability of teams to incorporate the atypical running conditions in their design causes multiple unforeseen issues. One such condition where the teams fail to improvise upon is the cooling system. Due to the high performance requirement of the competition, multiple teams participating face recurring heating problems. Maximum efficiency from a combustion vehicle can only be achieved when the cooling system is designed to handle the increasing power demand. This paper brings forth a detailed study on the intricate design of the cooling system. The problem has been approached using both theoretical and simulation models. Firstly, NTU-ℇ method was used to calculate the overall heat transfer coefficient and the temperature drop through the radiator core.
2018-04-03
Technical Paper
2018-01-0081
Pradip Dube, Sadashiv Hiravennavar, Abbas Ali Z
In a typical ground vehicle, airflow enters engine compartment through grill and carries heat from the engine, cabin and other auxiliaries through heat exchangers such as radiator, condensers and oil coolers and charge air coolers respectively. The amount of airflow entering the engine compartment is governed by their individual resistances, the grill and engine compartment resistances. This flow adds to drag and deteriorates overall aerodynamic efficiency. It is known as cooling drag which contributes to 8 to 12 percent of overall drag. Aerodynamics and Front End Air Flow (FEAF) development happens through CFD which require accurate heat exchanger pressure drop data and it is obtained from supplier at very early stages of a vehicle development. Historically, this data is found to have considerable variations compared to in-house test data.
2018-04-03
Technical Paper
2018-01-0080
Rezwanur Rahman, Sadek Rahman
The demand for vehicles with electrified powertrain systems is increasing due to government regulations on fuel economy. The battery systems in a PHEV (Plug-in Hybrid-electric Vehicle) have achieved tremendous efficiency over past few years. The system has become more delicate and complex in architecture which requires sophisticated thermal management. Primary reason behind this is to ensure effective cooling of the cells. Hence the current work has emphasized on developing a “Physics based” thermal management modeling framework for a typical battery system. In this work the thermal energy conservation has been analyzed thoroughly in order to develop necessary governing equations for the system. Since cooling is merely a complex process in HEV battery systems, the underlying mechanics has been investigated using the current model. The framework was kept generic so that it can be applied with various architectures. In this paper the process has been standardized in this context.
2018-04-03
Technical Paper
2018-01-0083
Ezio Mancaruso, Luigi Sequino, Bianca Maria Vaglieco
Internal combustion engines are characterized by high pressure and temperature loads on pistons and cylinders. The heat generated by the combustion process is dissipated by means of water and oil cooling systems. For the best design and optimization of the engine components is necessary to know the components temperature in order to estimate the thermal flows. The purpose of this work is to measure the piston sapphire window temperature in a research optically accessible engine by combining two different techniques: thermocouples measurements and thermography. The first is a well consolidated method that provides a reliable value of temperature. On the other hand, it requires high technical level to be applied because of the use of linkage systems to support the thermocouples wires or even more skills when wireless data transmission is set.
2018-04-03
Technical Paper
2018-01-0082
Eric C. Myers, Syed Ali
Jet pumps are viable options of pumping fluid if a pressurized flow stream is available as an energy source. For a Ford engine cooling circuit an effort was undertaken to improve an existing (conventional) jet pump design which could not meet more demanding pumped flow requirements. Various virtual jet pump designs were analyzed using 3D CFD where the pumped flowrate was used to evaluate the effectiveness of the design. It was found that the existing design could not be modified to provide the needed pump flow rate. It was decided to forgo the current design and develop a completely new configuration. This effort produced many design variances which were evaluated and resulted in a final design that closely reached the pumped flow rate requirements. As new designs were evaluated through the process, particular geometrical aspects were observed which improved the pumped flow performance.
2018-04-03
Technical Paper
2018-01-0084
Rohit Saha, Jagdeep Singh, Evangelos Koutsavdis, Hamid Ghazialam
Development of quick and efficient numerical tools is key to the design of industrial machines. While Computational Fluid Dynamics (CFD) techniques based on Navier Stokes (N-S) and Lattice Boltzman methods are becoming popular, predicting aeroacoustic behavior for complex geometries remains computationally intensive for design process and iteration. The goal of this paper is to evaluate application Navier–Stokes approach coupled with Ffowcs Williams and Hawkings (FW-H), Gutin’s model, and Broad-band Noise Model (BNS) to evaluate noise levels and predict design direction for industrial applications. Steady-state RANS based approaches are used to evaluate under-hood cooling performance and fan power demand. At each design iteration, noise levels and strength of noise source are evaluated using Gutin’s and broad-band noise models, respectively along with cooling performance. Each design feature selected for the final design has lower fan power and noise level with improved cooling.
2018-04-03
Technical Paper
2018-01-0085
Taichi Asano, Takashi Yasuda, Manabu Hasegawa, Jonathan Radzicki, Ken Muto, Michael John Tucker
Due to continuous environmental improvement trends in recent years, the use of turbocharged engines is expanding worldwide. The water cooled type CAC (WCAC) has the merit of simplifying the intake air path and is the current mainstream use of CACs. In this report, we introduce a newly-developed plate-type WCAC module that is integrated with the intake manifold and mounted directly onto the engine. The design length of the WCAC and shape of the module can change with different engine cylinder layouts. The module has crimped plastic tanks with large charge-air intake ports to obtain a smaller packaging and installation space. Therefore, the WCAC module shape, simple structure, and large intake ports allow for lower gas pressure loss and improved performance.
2018-04-03
Technical Paper
2018-01-0086
Azmi Osman, Razmi Mohd Razali, Nurul Nurdin
This study is a continuation of the earlier study published in SAE #2016-01-0647. The earlier test results have proven that the previously proposed engine cooling circuit when combined with exhaust heat recovery and reuse could expedite the warm-up process after cold-start and has improved the fuel economy by up to 4%. With the earlier concept being evolved further, the study discussed in this paper explores further improvements that can be made to the cooling circuit to further expedite the warm-up process. In particular, with some changes to the cooling circuit, the heat recovered from the exhaust gas can be reused right away to heat up the heat exchangers for engine oil, CVT oil and cabin heater before the coolant is recirculated into the engine. Next, the thermostat opening temperature and leakage rate can also be optimized to prolong the heat recirculation period.
2018-04-03
Technical Paper
2018-01-0088
Jiaxin Liu, Baozhong Wang, Yankun Jiang, Haiyang Long
Construction vehicles own some inherent characteristics, such as low velocity, high power and following heavy heat flux et al. Aim at decreasing flow resistance and managing airflow, a 39 ton single drum road roller from one of the biggest manufactures in China was employed as a research target to seek out the effect of air flow resistance on the performance of its heat dissipation system. For a start, a simplified 3D model of the road roller in a virtual wind tunnel was established with a commercial software, which was pre-processed in Gambit later. The radiators were set with heat exchanger boundary condition based on the analysis on the air-side elementary unit, as for the cooling fan, the experimental results in the wind tunnel were transformed into the corresponding boundary condition.
2018-04-03
Technical Paper
2018-01-0035
Anthony Navarro, Jendrik Joerdening, Rana Khalil, Aaron Brown, Zachary Asher
Autonomous vehicle development has benefited from sanctioned competitions dating back to the original 2004 DARPA Grand Challenge. Since these competitions, fully autonomous vehicles have become much closer to significant real-world use with the majority of research focused on reliability, safety and cost reduction. Our research details the recent challenges experienced at the 2017 Self Racing Cars event where a team of international Udacity students worked together over a 6 week period, from team selection to race day. The team’s goal was to provide real-time vehicle control of steering, braking, and throttle through an end-to-end deep neural network. Multiple architectures were tested and used including convolutional neural networks (CNN) and recurrent neural networks (RNN). We began our work by modifying a Udacity driving simulator to collect data and develop training models which we implemented and trained on a laptop GPU.
2018-04-03
Technical Paper
2018-01-0034
Santhosh Tamilarasan, Daniel Jung, Levent Guvenc
An important part of automotive driving assistance systems and autonomous vehicles is speed optimization and traffic flow adaptation. Vehicle perception sensors like radar and camera and wireless communication with surrounding vehicles and road infrastructure allows for predictive control strategies taking near-future road and traffic information into consideration to improve fuel economy. Evaluation in real-life traffic situations is difficult and experimental methods are necessary where similar driving conditions can be reproduced to compare different control strategies. Predefined velocity profiles such as FTP75, that the vehicle should follow, are traditionally used for evaluating fuel consumption. However, if the vehicle velocity is part of the vehicle control output, a different vehicle evaluation framework is necessary.
2018-04-03
Technical Paper
2018-01-0032
Toshiyuki Hasegawa, Jeff Wians
Technology is continuously being developed to prevent self-driving vehicles from crashing. That technology could also be considered for other autonomous products. Collision avoidance in automated, guided systems using a light detection and ranging (LIDAR) scanner has been studied for application in low-speed autonomous Honda Power Equipment products, such as self-driving lawnmowers. The automotive application of a LIDAR scanner for autonomous driving uses it to identify lane markings on pavement, by which an automated drive system can control lateral vehicle distance to avoid collisions. Such delineations do not exist in areas where power equipment is used, such as grass fields; therefore, identifying object height and distance instead, is a relatively new area. For this study, a small LIDAR scanner with a resolution of 0.01 m and a measurement range of 0.05 m to 40.00 m was used on a Honda self-driving lawnmower.
2018-04-03
Technical Paper
2018-01-0039
Lin Liu
To promote the development of automated vehicles(AVs), large scale of FOTs were carried out around the world. Application of naturalistic driving data from FOT to function definition and test and evaluation of AVs base on related scenarios. However, most of the existing scenario typologies, aiming at advanced driving assistance system(ADAS) and extracting relevant fragments from continuous driving process, are not suitable for AVs, which need to deal with continuous driving task. In this paper, a systematic scenario-typology consisting of four layers (from top to bottom: trip, cluster, segment and process) was first proposed. A trip refers to the whole duration from starting at initial parking space to stopping at final parking space. The basic unit of a trip is process, during which the vehicle fulfils only one task. According to diverse driving tasks, processes are classified into parking process, long-, middle- and short-time-driving-process.
Viewing 121 to 150 of 86934