Browse Topic: Throttles

Items (1,416)
Hybrid Electric Vehicles (HEVs) combine combustion and electric propulsion means to achieve key objectives, such as: reducing fuel consumption, minimizing pollutant emissions, and enhancing the overall energy efficiency of the Powertrain System. The series hybrid electric vehicles, in special, have a topology compound by four Subsystems, which are: Traction, Storage, Energy Generation, and Energy Management. The Energy Generation Subsystem is responsible for the power supply of the electric traction motors and batteries, depending on the control strategy promoted by the Energy Management Subsystem. The Energy Generation Subsystem is essentially made by an Internal Combustion Engine (ICE) and a Generator. Effective control of the power output from the Energy Generation Subsystem necessitates precise regulation of the engine speed. Thus, it is necessary to control the engine speed because this is directly related to the power demand of the consumers of other subsystem components. This
Júnior, João Marcos Hilário Barcelosde Sousa Oliveira, Alessandro BorgesTeixeira, Evandro Leonardo SilvaPereira, Bruno LuizPinheiro, Leandro Soaresdos Santos Ribeiro, Eduardodos Santos de Oliveira, Jordano
This SAE Recommended Practice describes two-dimensional, 95th percentile truck driver, side view, seated shin-knee contours for both the accelerator operating leg and the clutch operating leg for horizontally adjustable seats (see Figure 1). There is one contour for the clutch shin-knee and one contour for the accelerator shin-knee. There are three locating equations for each curve to accommodate male-to-female ratios of 50:50, 75:25, and 90:10 to 95:5
Truck and Bus Human Factors Committee
Sometimes, I cringe; sometimes, I just listen and wonder. These past few months have given us all a lot to think about in the automotive space, and it's clear now that the coming years will keep the foot down on the accelerator when it comes to the dramatic changes we've experienced this past decade. One thing that stood out to me in various recent conversations is that there's a widening gulf opening between Chinese automakers and the rest of the world. This isn't exactly news, and this column isn't meant to monger any fears. It's just a bit of off-the-cuff reporting that sheds a bit of light on the level of the challenges we face. As you can read in Chris Clonts' excellent report further in this issue about the warning that Voltaiq's CEO gave at The Battery Show this October, the U.S. is in serious danger of falling well behind Chinese competitors in the EV battery race (Michael Robinette tackles similar ground through a tariff lens in this month's Supplier Eye). But that message was
Blanco, Sebastian
The purpose of this SAE Recommended Practice is to provide guides toward standard conditions for operating marine engine throttles (gasoline or diesel) where push-pull cable control is applicable. For control cable information see SAE J917
Marine Technical Steering Committee
Based on the basic structure and operation function of engine throttle, according to the actual structure of a throttle, a 3-dimensional simulation of the transient airflow during the rotation of the throttle from the closed position to the fully open position is realized by using CFD together with the moving mesh technology and the user-defined program. The influence of the throttle movement on the airflow process is studied. The velocity field, pressure field, and flow noise field are analyzed at different angles of throttle rotation. The numerical simulation results show that at the beginning period of the throttle rotation, the vortex appears in the flow field behind the throttle, and the drop of the air pressure between the upstream and downstream position of the throttle is sharp. In addition, the results show that the flow noise field appears near the top dead center and bottom dead center of the throttle, and the maximum value of the acoustic power appears when the throttle
Yang, ShuaiDing, JieYan, KaiLiu, HaifengChen, Yilin
The present study aims to determine the comparative performance evaluation in terms of fuel economy (kmpl) and wide open throttle (WOT) power derived from set of different blends of high octane gasoline fuel(s) i.e., Neat Gasoline (E0), E10 & E20 (With different dosages of additives) in high compression ratio (HCR) motorcycle on chassis dynamometer facility. With the Government of India focus on use of alcohol as co-blend of gasoline with the endeavour to save foreign exchange and also to reduce greenhouse gases (GHG) emissions. The commercially available blended fuels, E10 & E20, have high research octane number (RON, 92-100) and as per the available literature high RON fuel have the better anti-knocking tendencies thereby lead to higher fuel economy. There are various routes to formulate high octane fuel (refining technologies, additive approach & ethanol blending route) in the range of 92-100 octane number which are currently commercialized in Indian market. In the present study
Saroj, ShyamsherKalita, MrinmoyKumar, PrashantKant, ChanderPatanwal, PradeepChakradhar, MayaSithananthan, MArora, Ajay KumarHarinarain, Ajay KumarMaheshwari, Mukul
Intelligent vehicle-to-everything connectivity is an important development trend in the automotive industry. Among various active safety systems, Autonomous Emergency Braking (AEB) has garnered widespread attention due to its outstanding performance in reducing traffic accidents. AEB effectively avoids or mitigates vehicle collisions through automatic braking, making it a crucial technology in autonomous driving. However, the majority of current AEB safety models exhibit limitations in braking modes and fail to fully consider the overall vehicle stability during braking. To address these issues, this paper proposes an improved AEB control system based on a risk factor (AERF). The upper-level controller introduces the risk factor (RF) and proposes a multi-stage warning/braking control strategy based on preceding vehicle dynamic characteristics, while also calculating the desired acceleration. Furthermore, a lower-level PID-based controller is designed to track the desired acceleration
Guo, ShaozhongGuo, JunZhang, YunqingWu, Jinglai
This paper defines a control method for shift torque exchange stage and a torque distribution control method for speed regulation stage. In the torque exchange stage, the torque distribution problem of active and passive clutches considers the injection of sine curve for local correction, which can solve the fish belly problem of hydraulic response (i.e. the hydraulic response is slow at the beginning and the hydraulic response is fast at the end). In the speed regulation stage, the target speed gradient profile is determined according to different shift types. The determination of the target speed gradient profile integrates different driving modes, throttle, P2 energy and clutch temperature. In the speed regulation stage, the torque distribution control problem of the speed phase including which actuator (P1, engine, C0 clutch) is used preferentially for speed regulation. a) If the speed regulation torque assigned to the input shaft exceeds the input shaft intervention torque
Jing, JunchaoZhang, JunzhiChen, JialuLiu, YiqiangHuang, Weishan
Diesel-fueled heavy-duty vehicles (HDVs) can be retrofitted with conversion kits to operate as dual-fuel vehicles in which partial diesel usage is offset by a gaseous fuel such as compressed natural gas (CNG). The main purpose of installing such a conversion kit is to reduce the operating cost of HDVs. Additionally, replacing diesel partially with a low-carbon fuel such as CNG can potentially lead to lower carbon dioxide (CO2) emissions in the tail-pipe. The main issue of CNG-diesel dual-fuel vehicles is the methane (CH4, the primary component of CNG) slip. CH4 is difficult to oxidize in the exhaust after-treatment (EAT) system and its slip may offset the advantage of lower CO2 emissions of natural gas combustion as CH4 is a strong greenhouse gas (GHG). The objective of this study is to compare the emissions of an HDV with a CNG conversion kit operating in diesel and dual-fuel mode during highway operation. Road tests were conducted on a three-axle Class-8 highway semi-trailer tractor
Dev, ShouvikQi, AiduAnderson, AndrewDahlseide, AustinSmith, BrettLussier, Simon-AlexandreGuo, HongshengRosenblatt, Deborah
This article investigates the performance of a low-cost throttle-by-wire-system (TbWS) for two-wheeler applications. Mopeds/scooters are still restricted as environmentally harmful. TbWSs can contribute to environmental protection by replacing conventional restrictors. Its consisting of an anisotropic magnetoresistance (AMR) throttle position sensor and a position-controlled stepper motor-driven throttle valve actuator. The decentralized throttle position sensor is operating contactless and acquires redundant data. Throttle valve actuation is realized through a position-controlled stepper motor, sensing its position feedback by Hall effect. Using a PI controller, the stepper motor position is precisely set. Both units transmit and receive data by a CAN bus. Furthermore, fail-safe functions, plausibility checks, calibration algorithms, and energy-saving modes have been implemented. Both modules have been evaluated through hardware-in-the-loop testing in terms of reliability and
Kreß, JannisRau, JensHebert, HektorSchmidt, KarstenPerez-Peña, FernandoMorgado-Estévez, Arturo
Methanol, a fuel obtainable through the capture and conversion of Carbon Dioxide (CO2), has garnered attention as a suitable alternative fuel for gasoline. Methanol-gasoline blends, characterized by their high-octane rating, commendable performance, and reduced carbon emissions, present themselves as promising alternative fuels for internal combustion engines. In the present study, a comprehensive comparative analysis was conducted to assess the performance and emissions characteristics of unmodified vehicles utilizing methanol blends at lower concentrations, ranging up to 30%, in gasoline. The research focused on two distinct classes of vehicles commonly found on the roads of India: those compliant with BS-IV (Euro IV) and BS-VI (Euro VI) emission standards. Experimental evaluations were carried out on a chassis dynamometer, with the vehicles subjected to the Worldwide Harmonized Motorcycle Test Cycle (WMTC) and Wide open throttle (WOT) driving tests. The emissions from these vehicles
Teja, RaviKhandai, ChinmayanandaMuralidharan, M
In today's volatile market environment, and with the change of user priorities, NVH refinement results in silent, vibration-free vehicle. The commercial vehicle industry is also starting to embrace this development in NVH vehicle refinement. There are health concerns associated with the discomfort experienced by occupants. This calls for cabins with no boom noise and less tactile vibrations. Noise within the vehicle is contributed by excitation from the Powertrain, Intake, Exhaust system, driveline, road excitations, suspension (structure borne noise) and its radiation into the air (air borne noise). This paper discusses the approach used to reduce “In-cab boom” noise in the operating speed sweep condition and seat track vibration during engine IDLE condition to improve driver comfort. In this paper NVH refinement was carried out on small commercial vehicles. Higher Seat track vibrations during IDLE and cabin boom noise during wide open throttle condition were observed during
Yeola, YogeshKharpude, YogeshKalsule, DhanajiChoudhary, AdityaSonar, SantoshNikam, Avinash
The development and improvement of efficient compressed natural gas (CNG) engines align with efforts to reduce greenhouse gas and pollutant emissions. The objective of this study is to evaluate the flame structure and compare the performance characteristics of an engine powered by compressed natural gas (CNG) under stoichiometric and lean combustion in wide open throttle. CFD simulation alongside experimental tests are performed. The experimental data were obtained using a Hyundai 2.5-liter HR engine, originally a Diesel engine, adapted for spark ignition operation. Lean and stoichiometric conditions were evaluated at compression ratio 14:1, operating at 1800 rpm in MBT spark timing. The results showed that increasing lambda (λ) had a significant effect on apparent heat release rate, laminar flame speed, flame thickness and flame surface area. While the flame speed decreased in a leaner operating condition, the flame thickness and surface area increased due to reduced reaction rates
da Silva, Cristian Douglas RosaFrança, Louise Bomfim MagalhãesFagundez, Jean Lucca SouzaLanzanova, Thompson Diórdinis MetzkaMartins, Mario Eduardo Santos
Rotary valve technology can provide increased flow area and higher discharge coefficients than conventional poppet valves for internal combustion engines. This increase in intake charging efficiency can improve the power density of four-stroke internal combustion engines, particularly at high engine speeds, where flow is choked through conventional poppet valves. In this work, the valvetrain of a light duty single cylinder spark ignition engine was replaced with a rotary valve train. The impact of this valvetrain conversion on performance and emissions was evaluated by comparing spark timing sweeps with lambda ranging from 0.8 to 1.1 at wide open throttle. The results indicated that the rotary valvetrain increased the amount of air trapped at intake valve closing and resulted in a significantly faster burn duration than the conventional valvetrain. Additionally, the spark to CA10 burn duration of the rotary valvetrain was highly sensitive to spark timing, which was not true of the
Gainey, BrianVaseleniuck, DarrickCordier, DanGarrett, Norman
Estimated engine torque is an important parameter used by automotive systems for automated transmission and clutch control. Heavy-duty engine and transmission manufacturers widely use SAE J -1939 based ECU torque calculation based on mass air/fuel flow steady state maps created during calibration of the engine for this purpose. As an alternative, to enhance the accuracy of this important control variable, a virtual flywheel torque sensor (VFTS) was developed. It measures the engine torque based on the harmonics of the instantaneous flywheel speed signal. Initial dynamometer testing showed the VFTS estimated torque values exhibited a maximum inaccuracy of 12% of the actual measured torque over the range of conditions tested. In this paper we report the results of on road truck testing of the VFTS. A loaded heavy truck with a gross vehicle weight rating of 80,000 pounds was used. The performance of the VFTS was tested in different gears at full throttle in the diesel engine speed range
Iddum, VivekBair, JohnChahal, Iqbal SinghMason, PaulGhantasala, Muralidhar K.
The design and development of a hydrogen powered spark-ignition engine, aimed for installation on a vehicle for on-road application. The experiment was conducted at WOT (Wide Open Throttle) condition at a speed of 4000 rpm with an excess air-fuel ratio of 1.3, 1.5, 2.2, 2.5, 3, 3.75, and 4.0. The ignition timing was optimized for maximum torque at each value of the excess air ratio. The various parameters analyzed such as in-cylinder pressure, Pressure and Volume, Logarithm of Pressure and Volume, Mass fraction burned, Cummulative heat release, Net heat release, Rate of pressure rise, and Mean gas temperature. The results show that there is a profound effect of excess air-fuel ratio on the engine’s mean effective pressure, output power, Brake thermal efficiency, Volumetric efficiency, Brake specific fuel consumption, and NOx emissions. The peak cylinder pressure decreases with an increase in excess air-fuel ratio and NOx emissions are reduced due to reduced mean gas temperature. Also
Shinde, ApurwaKARUNAMURTHY, KSHINDE, BALU JALINDARRairikar, SandeepThipse, Sukrut S
Dedicated-EGR™ (D-EGR™) is a concept where the exhaust of one dedicated cylinder (D-Cyl) is routed into the intake thus producing EGR to be used by the whole engine. The D-Cyl operates rich of stochiometric which produces syngas that enhances the EGR stream permitting faster combustion and greater knock mitigation. Operating an engine using D-EGR improves the knock resistance which can permit a higher compression ratio (CR) thereby increasing efficiency. One challenge of traditional D-EGR is that the D-Cyl combustion becomes unstable operating with both rich and EGR dilute conditions. Therefore, the ‘Split Intake D-EGR’ concept seeks to resolve this problem by feeding fresh air to the D-Cyl, thus allowing even richer operation in the D-Cyl which further increases the H2 and CO yield thereby enhancing the efficiency benefits. This concept was employed on a downsized PSA EP6CDTx 1.6 L gasoline engine with a baseline BMEP of 20 bar, a CR of 10.5:1, and a peak brake thermal efficiency (BTE
Handa, GauravConway, GrahamRobertson, DennisGukelberger, Raphael
Precise measurement of Air-fuel ratio (AFR) or Lambda value plays a substantial role in controlling exhaust emission from an internal combustion engine. Estimation of AFR is a significant factor to determine the engine performance and to optimize the catalyst conversion efficiency which has direct impact on increase or decrease of emissions. Most of the production two-wheeler engine determines AFR by using non-linear lambda sensor (Narrow band oxygen sensor) but it limits the AFR control due to restrictions in its performance and operating time. A wideband lambda sensor is more accurate and faster but may not be economical to place on low-cost vehicles. A time varying ion current signal can be easily captured on vehicle with minimal additional requirements. AFR has direct correlation with various engine parameters such as Engine speed, Throttle position sensor (TPS), Manifold air pressure (MAP), Fuel injection pulse width (FPW), etc. These signals can be captured with the pre installed
Bagade, Monika JayprakashDas, HimadriMandloi, DeepakR, Harini
In the automotive industry, performing steady-state tests on an internal combustion engine can be a time consuming and costly process, but it is necessary to ensure the engine meets performance and emissions criteria set by the manufacturer and regulatory agencies. Any measures that can reduce the amount of time required to complete these testing campaigns provides significant benefits to manufacturers. The purpose of this work is then to develop a systematic approach to minimize the time required to conduct a steady-state engine test campaign using a Savitsky-Golay filter to calculate measured signal gradients for continuous steady-state detection. Experiments were conducted on an Armfield CM11-MKII Gasoline Engine test bench equipped with a 1.2L 3-cylinder Volkswagen EA111 R3 engine. The test bench utilizes throttle position control and an eddy current dynamometer braking system with automatic PID control of engine speed. Data from engine signals (e.g. exhaust temperature, engine
DeCoste, StevenScalzi, AntonioChen, JunDelVescovo, Dan
For cooperative adaptive cruise control (CACC) system, a robust following control algorithm based on fuzzy PID principle is adopted in this paper. Firstly, a nonlinear vehicle dynamics model considering the lag of driving force and acceleration constraints was established. Then, with the vehicle’s control hierarchic, the upper controller takes the relative speed between vehicles and the spacing error as inputs to output the following vehicle's target acceleration, while the lower controller takes the target acceleration as inputs and the throttle opening and brake master cylinder pressure as outputs. For the setting of target spacing, this paper additionally considers the relative speed between vehicles and the acceleration of the front vehicle. Through testing, compared with the traditional variable safety distance model, the average distance reduces by 5.43% when leading vehicle is accelerating, while increases by 2.74% in deceleration. For the fixed-speed cruise mode, a set of logic
Zhu, MingyangTan, Gangfeng
This SAE Standard establishes a uniform test procedure and performance requirements for off throttle steering and obstacle avoidance capabilities of personal watercraft. Personal watercrafts intended to be operated by a single operator who either stands or kneels in a tray located behind a moveable handlepole are exempted from this SAE Standard. This SAE Standard does not apply to outboard powered personal watercraft and jet powered surfboards
Personal Watercraft Committee
Personal watercraft (PWC) users and other high-speed watersports participants have sustained rectal and vaginal injuries during falls into the water, herein referred to as water intrusion injuries (WIIs). WIIs result from the rapid introduction of water into these lower body cavities causing injury to the soft tissues of the perineum, rectum, and vagina. While case studies of injured water-skiers and PWC users are reported in the literature, there is little information related to passenger kinematics and pressure exposure during a rearward fall from a PWC. The results of an experimental study of passenger falls from two “high-performance” PWC are presented herein. A human passenger was caused to fall rearward as the PWC was accelerated at maximum throttle starting from idle speed (≈3–4 mph) and planing speeds of ≈20–30 mph. The subject passenger fell from the aft seat position and while standing on the rear platform. Aerial and shore-based cameras were used to document passenger
Winkel, Eric S.Zakutansky, Katie B.Schirmann, MatthewBreen, Kevin C.Taylor, Robert K.
The digital control of a dynamometer is essential for test of internal combustion engines, because it acts in command of the testing routine. This work consists in the PID (proportional, integrative and derivative) control of the Foucault current dynamometer, from the Institute of Technological Research - IPT. During the control development was made plant differents types, and differents controllers, that was validated by form experimental and theory. Digital controls were achieved using LabVIEW® and Simulink® software, which served to compare and simulate them, thereby making possible a validation. For the system in real-time, controlled by LabVIEW®, it was necessary to identify the dynamometer model, which corresponds to an eddy current brake, model I2D. The speed control developed by means of these tools is intended to adjust the speed of the dynamometer. In order to carry out the tests, this speed parameter must follow the desired values (set point) and maintain the relationship of
da Mata, Valter Manuel JardimMoscardini, Demersonda Silva Pereira, Bruno , AntônioMaria Laganá, Armando
Achieving higher emission norms involves various techniques and it has always been a challenging task on meeting the same. Improving the exhaust temperature is indispensable in order to enhance better conversion efficiency on the after-treatment systems. This paper clearly investigates on the various strategies involved to improve the exhaust temperatures of selective catalytic reduction and post injection strategies to meet the emission norms. On the basis of MIDC operation, key load points were selected and split injections with three pulses were implemented. The variation of both the post injection timing and quantity were performed in this paper in order to evaluate the optimum output. The effect of post injection timing and quantity variation on hydrocarbon emissions, carbon monoxide, diesel oxidation catalyst temperatures was observed on all load points. The above strategy was also evaluated on generating the pressure crank angle data. SCR efficiency improvement was investigated
Anbarasu, MuthusamyShangar Ramani, Vagesh
Turboprop aircraft have the capability of reversing thrust to provide extra stopping power during landing. Reverse thrust helps save the wear and tear on the brakes and reduces the landing distance under various conditions. The article explains a methodology to predict the disking drag (reverse thrust) from the Computational Fluid Dynamics (CFD) technique using Blade Element Momentum (BEM) theory and estimation of the same from high-speed taxiing trial (HSTT) and ground roll data for a turboprop aircraft using system identification techniques. One-dimensional kinematic equation was used for modeling the aircraft dynamics, and the error between measured and estimated responses was optimized using the Output Error Optimization Method (OEOM). The estimated propeller drag was matched with CFD predictions to arrive at a relation between the propeller blade pitch angle and throttle position. The present study also investigates the estimation of the braking friction coefficient from the
Nusrath T. K., KhadeejaKaliyari, DushyantPuttam, Jyothi KumarMadhu Babu, K.Arshad Shameem, C.Jaiswal A, ShikharSajjan, Sharanappa V.Venkatesh, T. N.Pashilkar, Abhay A.
This SAE Aerospace Standard (AS) provides general design and test requirements for a flat cut-off pressure compensated, variable delivery hydraulic pump for use in a civil aircraft hydraulic system with a rated system pressure up to 5000 psi (34500 kPa). NOTE: Hydraulic pumps may incorporate features such as a clutch in the input drive, which will not be covered by this standard
A-6C4 Power Sources Committee
Automatic Transmissions managements are often based on throttle position and vehicle speed and mainly aim to reduce fuel consumption and carbon dioxide (CO2) emissions, in vehicles equipped with Internal Combustion Engines (ICE). This is an important goal from two viewpoints: fuel economy and greenhouse gases (GHG) containment, with benefits in terms of global warming and climate change. At the same time, traffic stops are due to the detection of other pollutants, as nitrogen oxides (NOx) and particulate matter (PMx), which are harmful for human health. This is particularly true in urban areas, especially during traffic jams. Moreover, localized high levels of the pollutants produced may not be detected by conventional and relatively far air quality detection stations. In this paper, a solution to efficiently detect air quality parameters near the vehicles is proposed, with the development of on-board low-cost monitoring air quality systems and a Vehicle to Vehicle (V2V) communication
Scaffidi, Carlo AlessioTricomi, GiuseppePuliafito, AntonioDistefano, Salvatore
The purpose of this SAE Recommended Practice is to provide a common electrical and mechanical interface specification that can be used to design electronic accelerator pedal position sensors and electronic control systems for use in medium- and heavy-duty vehicle applications
Truck and Bus Electrical Systems Committee
After years of lukewarm reception and limited funding, it looks as if the battery electric vehicle (BEV) market is finally going full throttle. According to a recent Forbes article, Schmidt Automotive Research recently reported that BEV sales more than doubled in 2020 to nearly 750,000 and jumped again in 2021 with sales of more than one million vehicles, despite an ongoing chip shortage and pandemic-related disruptions
With the increase of electric vehicles on the roads, there is also an increase with vehicles that use regenerative braking (RB). This novel braking method differs from traditional service braking (SB) because RB decelerates the moment the driver releases the accelerator pedal and continues to actively brake if neither pedal is depressed. Since the vehicle actively decelerates when neither pedal is depressed in a vehicle with RB, we hypothesized that this would result in a difference in driver foot behavior. There were two pieces to explore this potential difference. The first piece was to explore time-based measures. The first measure was the time period from when the lead vehicle brake lights illuminate, to when the driver releases the accelerator pedal. The second measure was the time period from when the driver releases the accelerator pedal, to when the driver presses the brake pedal. When comparing RB and SB, there was no statistically significant difference for the first time
Rundus, Christopher Robert MitropoulosMcGehee, Daniel V.Schwarz, Chris W.
As one of the key components of the heat pump system, the electronic expansion valve mainly plays the role of throttling and reducing pressure in the heat pump system. The refrigerant flowing through the orifice will produce complex phase change. It is of great significance to study the internal flow field by means of CFD calculations. Firstly, a three-dimensional fluid model is established and the mesh is divided. Secondly, the phase change model is selected, the material is defined and the boundary conditions are determined. According to the principle of the fluid passing through thin-walled small holes, the flow characteristics of electronic expansion valve are theoretically analyzed. Then the flow characteristics of expansion valve are numerically calculated, and a bench for testing mass flow rate of the expansion valve is built. Then the theoretical value, CFD value and experimental value are compared to verify the correctness of the established three-dimensional fluid model. The
Liang, GaoshuaiLi, LipingShangguan, Wen-Bin
Pedal misapplication (PM) crashes, i.e., crashes caused by a driver pressing one pedal while intending to press another pedal, have historically been identified by searching unstructured crash narratives for keywords and verified via labor-intensive manual inspection. This study proposes an alternative method to identify PM crashes using event data recorders (EDRs). Since drivers in emergency braking situations are motivated to hit the brake hard, it follows that drivers in emergency braking situations that commit a PM would likewise hit the accelerator hard, likely harder than accelerator pedal application during normal driving. Thus, the time-series accelerator pedal position and the derived accelerator pedal application rate were used to isolate accelerator misapplications. Additional strategic filters were applied based on characteristics observed from previous PM analyses to reduce false positive PM identifications. These include a crash type filter, since PM crashes have been
Smith, Colin PSherony, RiniGabler, H. ClayRiexinger, Luke E
Electronic expansion valve as a throttle element is widely used in heat pump systems and flow characteristics are its most important parameter. The flow characteristics of the electronic expansion valve (EXV) with a valve port diameter of 3mm are studied, when the refrigerant R134a is used as the working fluid. The main factors affecting the flow characteristics are researched by adopting the orthogonal experiment method and single factor control method, for example, inlet pressure, inlet temperature, outlet pressure and valve opening. The results show that the expansion valve opening degree has the greatest influence on mass flow rate. In view of the complicated phase change of the refrigerant passing through electronic expansion valve, it is difficult to model the flow characteristics accurately. Based on the measured experimental data, an improved particle swarm optimization algorithm whose learning factor can be dynamically adjusted is used to optimize the initial weights and
Liang, GaoshuaiLi, LipingShangguan, Wen-Bin
Autonomous driving technology, as the product of the fifth stage of the information technology revolution, is of great significance for improving urban traffic and environmentally friendly sustainable development. Autonomous driving can be divided into three main modules. The input of the decision module is the perception information from the perception module and the output of the control strategy to the control module. The deep reinforcement learning method proposes an end-to-end decision-making system design scheme. This paper adopts the Deep Deterministic Policy Gradient Algorithm (DDPG) that incorporates the Priority Experience Playback (PER) method. The framework of the algorithm is based on the actor-critic network structure model. The model takes the continuously acquired perception information as input and the continuous control of the vehicle as output. Combined with the CARLA simulation environment, the state space of the CNN network based on the input of the car's front
YK, ShiWu, JianSong, Shiping
The influence of driver modeling and drive cycle target speed trace modification on vehicle dynamics within energy consumption simulations is studied. EPA dynamometer speed error criteria and the SAE J2951 Drive Quality Evaluation for Chassis Dynamometer Testing standard are applied to simulation outputs as proposed components of simulation validation, providing guidelines for acceptable vehicle speed outputs and allowing comparison of simulation results to reported EPA dynamometer test statistics. The combined effect of driver model tuning and drive cycle interpolation methods is investigated for the UDDS, HwFET and US06 drive cycles, with EPA-specified linearly interpolated speed trace and a PI controller driver as a baseline result. Additional benefits of driver tuning are presented including a reduction in unnecessarily-aggressive simulated accelerator and brake pedal actuation, resulting in a drop of over 70% for peak jerk, 60% for RMS jerk, 80% for ripple aggressiveness, and 20
Legg, ThomasNelson, Douglas
This study demonstrates how SAE standard J1349 ambient correction factors are applied across varied powertrain electrification levels and xEV architectures. To study this phenomenon, these powertrain were evaluated (in vehicle, real road) at varied ambient pressures and temperatures to observe performance changes. 0-100kph wide open throttle acceleration time results were reported as a proxy for power/torque figures normally produced on an engine test bench in controlled laboratory conditions (per J1349). Observing results, it is clear that minimal to no ambient effects are observed on powertrains of high electrification, sometimes requiring zero normalization. The challenge to low-mid electrification/hybridization testing is understanding how to apply SAE J1349 ambient correction factors to accurately normalize results. To accomplish this, an Energy Ratio Method was developed to identify energy contributions within the powertrains. The results are a more accurate normalized
Schlingmann, Dean
This paper introduces a new systematic workflow for the rapid evaluation of energy-efficient automated driving controls in real vehicles in controlled laboratory conditions. This vehicle-in-the-loop (VIL) workflow, largely standardized and automated, is reusable and customizable, saves time and minimizes costly dynamometer time. In the first case study run with the VIL workflow, an automated car driven by an energy-efficient driving control previously developed at Argonne used up to 22 % less energy than a conventional control. In a VIL experiment, the real vehicle, positioned on a chassis dynamometer, has a digital twin that drives in a virtual world that replicates real-life situations, such as approaching a traffic signal or following other vehicles. The real and virtual systems interact in a close-loop fashion: the automated driving control directs accelerator and brake pedals based on measurements from the real vehicle and from the perception of the digital twin’s surrounding
Jeong, JongryeolKarbowski, DominikKim, NamdooHan, JihunStutenberg, KevinDi Russo, MiriamGrave, Julien
The advent of autonomous driving features has brought about the rise of new automotive technologies such as drive-by-wire. But the implementation of these technologies on physical vehicles is more complex, creating a need for simulation, model-based development, and testing of these systems before they are implemented in an actual vehicle. The real-time simulations capabilities of MATLAB and Simulink provide a robust development platform for behavioral cloning. The most common high-fidelity model used for simulation of vehicle dynamics is the 14 DoF model. Ackerman steering geometry has been around for two centuries and it is the most commonly used steering geometry for passenger cars. Yet, 14 DoF vehicle simulation models in literature have been observed to be using parallel steering geometry due to their simplicity. This paper focuses on developing a 14 DoF model with Ackerman steering geometry and presents a comparative study of Ackerman and Parallel steering geometries in 14 DoF
A, Aman BasheerDorle, AniruddhaTroy, PatShukla, Adhip
Development of propulsion control systems frequently involves large-scale transient simulations, e.g. Monte Carlo simulations or drive-cycle optimizations, which require fast dynamic plant models. Models of the air-path—for internal combustion engines or fuel cells—can exhibit stiff behavior, though, causing slow numerical simulations due to either using an implicit solver or sampling much faster than the bandwidth of interest to maintain stability. This paper proposes a method to reduce air-path model stiffness by adding an impedance in series with potentially stiff components, e.g. throttles, valves, compressors, and turbines, thereby allowing the use of a fast-explicit solver. An impedance, by electrical analogy, is a frequency-dependent resistance to flow, which is shaped to suppress the high-frequency dynamics causing air-path stiffness, while maintaining model accuracy in the bandwidth of interest. The proposed impedance method is demonstrated for a simple two-state
Brewbaker, ThomasVigild, Christian
We present our approach to several control challenges in high-speed autonomous racing for the Indy Autonomous Challenge (IAC). The IAC involves autonomous head-to-head racing at speeds approaching 200 mph. The autonomy system must maintain traction and stability when operating at such high speeds while also maneuvering aggressively around other competitor vehicles. One key challenge arises from limited actuator update frequency. We propose two lateral control methods to follow the desired trajectory: a cross-track error method and a pure pursuit lookahead angle method. Analysis shows that, when linearized, cross-track error and pure pursuit angle are related by a first-order system. To analyze the effect of actuator update frequency on closed-loop performance, we emulate the discrete rate as a time delay. Control parameters and gains for both controllers can be solved by using loop-shaping techniques to guarantee closed-loop bandwidth and phase margin. The bandwidth is limited by the
Manna, Rohan KumarGonzalez, Daniel J.Chellapandi, VishnuMar, ManuelKannan, Shyam S.Wadekar, ShaktiDietz, Eric J.Korpela, Christopher M.El Gamal, Aly
In order to resolve global atmospheric environmental issues, latest diesel engines for industrial machinery are required to reduce the emission of harmful gases such as carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx), and particulate matter (PM). For this reason, it is essential to mount exhaust gas after treatment devices such as diesel particulate filter (DPF) and diesel oxidation catalyst (DOC) on diesel engine. Engines mounted DPF must carry out DPF regeneration that burns and removes PM. Generator engine has characteristic of being operated for a long time under light load condition with low exhaust temperature which is difficult for DPF regeneration. In addition, generating white smoke and inlet face clogging of DOC are caused by accumulated soot containing HC at the DOC when operating engine continuously under light load condition. In this study, DPF regeneration system suitable for generator engine and method for preventing white smoke and inlet face clogging of
Kato, DaichiOkano, HiroakiInoue, KatsushiNakano, Kota
Among industrial engines, vortex chamber diesel engines are mainly used in small engines with output of less than 19 kW, and they employ an indirect injection system in which fuel is injected into a sub-chamber called a vortex chamber. The throttle-type nozzle used in swirl-chamber diesel engines is expected to change its spraying behavior depending on ambient conditions because the pressure fluctuations in the nozzle cause the needle valve to lift, and the injection amount is controlled by the amount of lift of the needle valve. In addition, the dimensions of the vortex chamber of a vortex chamber diesel engine are smaller than the spray development distance, and wall impingement of the spray is expected. In this study, spraying and combustion experiments were conducted using a constant volume chamber to understand the behavior of the spray from a throttle-type nozzle. Then, based on the obtained data, we developed a numerical simulation model to reproduce the hollow spraying behavior
Sudo, ZentaZhou, BeiniHozen, YumaKusaka, JinAjiro, KenyaKoga, Tomohiro
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