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Viewing 1 to 30 of 18629
2016-05-01
Technical Paper
2015-01-9147
Zhiyun Zhang, Miaohua Huang, Yupu Chen, Shuanglong Zhu
In the field of Electric Vehicle (EV), what the driver is most concerned with is that whether the value of the battery's capacity is less than the failure threshold because of the degradation. And the failure threshold means instability of the battery, which is of great danger for drives and passengers. So the capacity is an important indicator to monitor the state of health (SOH) of the battery. In laboratory environment, standard performance tests can be carried out to collect a number of related data, which are available for regression prediction in practical application, such as the on-board battery pack. Firstly, we make use of the NASA battery data set to form the observed data sequence for regression prediction. And a practical method is proposed to determine the minimum embedding dimension and get the recurrence formula, with which a capacity model is built.
2015-09-29
Technical Paper
2015-01-2879
Evandro Silva
In recent years the commercial vehicle industry, specifically the heavy duty truck product line, has seen a rapid increase in the replacement of pure mechanical systems by electronic controlled systems. Engine, transmission, brakes, lighting, clusters, etc. are all monitored and/or controlled electronically. The adoption of electronic systems created a substantial change in the complexity of our products. Currently Diagnostic Trouble Codes (DTC) displayed on instrument clusters, in the majority of the cases, are no longer generated by a single sensor/component failure, instead these DTCs are triggered by a system monitor flag, result of a below average performance or a failure of an entire system. This new level of complexity makes it very difficult for the current diagnostic methods and tools, to identify what is causing the equipment to operate below ideal conditions.
2015-09-29
Technical Paper
2015-01-2866
Saeil Jeon, Stacey Spencer, Paul Joiner
Lightweight solution is one of the keywords that we see every day. Developing smart, light and durable materials is one focal area that is inevitable to be done in the ground transportation sector. Another angle to look for is the protection and beautification of the substrate finish where surface treatment technology stands out. Combining both aspects is crucial in the industry for customer satisfaction. Recycled carbon fibers are used to form the reinforcement in the composite side, where they are infused or mixed with the matrix materials either in SMC (Sheet Mould Compound) or BMC (Bulk Mould Compound) format, depending upon the application. Glass fibers are usually used for the practical application, however considering further weight cut on the component, carbon fibers cannot be overlooked for their superior mechanical properties. However, due to the cost of carbon fibers many times the application may be over-designed.
2015-09-29
Technical Paper
2015-01-2901
Shaoyun Sun, Genghua Liao, Qiang Fu, Kelong Lu, Jing Zhao, Zhengzheng Li, Jiaquan Chen, Guang Shi, Sacha Jelic, Bo Li
Trucks are designed to carry heavy load, which implies high demanding design criteria for save operation. Heavy load means a lot of energy is needed to displace the load. During a stop, the kinetic energy is transferred into heat, which can be problematic in case of excessive proportions and/or when the heat cannot be removed from the system properly. The brake system therefore needs to be designed such to be able to absorb large of amount of heat and transfer the heat out of its system by either convection, conduction and/or radiation. All three heat transfer modes play an important role since the drum brakes of trucks are not much exposed to external airflow, a significant difference from disk brakes of passenger cars analyzed in previous studies. This makes it a complex heat transfer problem which is not easy to understand. Numerical methods provide insight by visualization of the different heat transfer modes.
2015-09-29
Technical Paper
2015-01-2845
Qi Chen
Recent years have witnessed an increase in the number of electrical loads being driven by semiconductor devices in the body control module or BCM rather than by relays in a typical truck with a 24V vehicle power net. This paper presents the major challenges caused by the higher voltage class of the truck supply and the longer cables, followed by an analysis of some key issues related to the design of truck BCMs to drive different loads. It offers some general guidance on practical design issues to BCM designers, such as an understanding of the advantages and disadvantages of different BCM architectural topologies, how to make a choice between a relay or a semiconductor driver, knowledge of the requirements of semiconductors used in truck applications etc.
2015-09-29
Technical Paper
2015-01-2766
Sai Venkatesh Muravaneni, Egalaivan Srinivasan, Jagankumar Mari
Steering wheel being the most used tactile point in a vehicle, its feel and response is an important factor based on which the vehicle quality is judged. Engineering the right feel and response into the system requires knowledge of the objective parameters that relate to the driver perception. Extensive correlation work has been done in the past pertaining to passenger cars, but the driver requirements for commercial vehicles vary significantly. Often it becomes difficult to match the right parameters to the steering feel experienced by the drivers since most of the standard units used to describe them are of zero or first order parameters. Analyzing the second order parameters gave a better method to reason driver related feel. Also, each subjective attribute was fragmented into sub-attributes to identify the reason for such a rating resulting in the identification of the major subjective parameters affecting driver ratings.
2015-09-29
Technical Paper
2015-01-2852
Daniel Ribeiro, Rodrigo Chaves, Rogerio Curty Dias, Gian Marques
In order to evaluate the opportunities to use hybrid concepts for heavy commercial vehicles for emerging markets, MAN Latin America has developed a VW refuse truck with 23t GVW using the hybrid hydraulic technology. In site vehicle tests measurements has indicated a fuel savings up to 25%, which means a reduction around 4.08 liters of diesel/hour or 20 tones CO2/year . Thus, a collaborative cooperation with Rio de Janeiro Sanitation Department (Comlurb) was set for a truck evaluation on a real operation. This 03-month evaluation used one VW 17.280 6x2 hybrid hydraulic refuse truck and other VW refuse truck similar standard diesel. A random dispatch system ensures the vehicles are used in a similar manner. Global positioning system logging, fueling, and maintenance records are used to evaluate the performance of this hybrid hydraulic refuse truck.
2015-09-29
Technical Paper
2015-01-2745
Florian Bauer, Jan Fleischhacker
A Hardware-in-the-Loop (HiL) system for Electronic Control Units (ECU) of electro-pneumatic brake systems is presented. The HiL system runs a real-time capable vehicle model comprising of both the vehicle dynamics and the electro-pneumatic brake system. The dynamic behaviour of the vehicle can be simulated either by a real-time multi-body vehicle model or by a simpler system dynamic (double-track) model. To assess the quality of the system dynamic vehicle model, it was compared to the multi-body vehicle model which was validated with comprehensive experimental results. Discrepancies can be seen for highly unsteady manoeuvres. Reasons for these discrepancies caused by the modelling topology of the system dynamic vehicle model will be given. In order to simulate the electro-pneumatic brake system, a real-time model has been developed and validated. The different topologies of brake systems can be assembled from components and integrated into the vehicle model.
2015-09-29
Technical Paper
2015-01-2753
Xiujian Yang, Ruocheng Zhu, Jin Gao
Tractor semi-trailer as a type of widely-used heavy duty freight vehicle is with relatively poor handling and lateral stability and is easy to fall into a lateral instability such as jackknife, trailer swing even causing an fatal accident. In this paper, attention is concentrated on a novel design concept for a tractor semi-trailer vehicle to improve the handling and lateral stability performances comprehensively by optimizing the whole vehicle arrangement and relevant design parameters. According to the previous public reports, the indexes such as Load Transfer Ratio(LTR), Static Rollover Threshold (SRT), Rearward Amplification Ratio (RWA) and Ratio of Yaw Rate (RYR) as very effective measures are often used to evaluate the handling and stability performances for a tractor-trailer vehicle. However, each of those indexes works individually and only focuses on a certain aspect with less relations to others.
2015-09-29
Technical Paper
2015-01-2797
Meichun Peng, Yue Zheng, Xiaoyan Jiang, Jiahao Wang
This paper studies the characteristics of fuel consumption and emission of city transit buses,and analyzes the fuel conservation and emission reduction rate of LPG-HEV buses relative to LPG bases. The run speed, fuel consumption and the exhaust emission,etc. of 3 LPG-HEV buses and 2 LPG buses were tested by a portable emission measurement system (PEMS) under real driving world of city transit buses at Guangzhou in China. The test data was analyzed, and the test results were compared between LPG-HEV buses and LPG buses. The study results show the buses run below than 35 km/h and in acceleration region of -0.5~0.5 m/s2 mainly, the average speed is 18 km/h. The average fuel consumption of LPG-HEV buses is 51.02 l/100km with a drop of 6.23% compared with LPG buses, and the fuel saving appears below than 25 km/h, the lower the speed, the more obvious the effect of fuel saving.
2015-09-29
Technical Paper
2015-01-2799
Shaopeng Tian, Yang Wang, Lei Wu
Dynamic and economic performance play an important role in the vehicle evaluation indexes, and also are crucial parts considered during the design progress. This paper applies a method of parameters matching of the powertrain to one pure electric bus, with which a four-speed transmission dynamic system is designed. Meanwhile two powertrain models adopting motors with identical peak power but different base speeds and peak torques coupled with three-speed transmission or without transmission are introduced for comparison. The three models are based on identical type of bus. Then according to the powertrain parameters, simulation models of three bus models are established respectively. From the results of simulation, vehicle performances of the four-speed transmission powertrain, especially economic performance, are compared with the other two. At last, results show that the four-speed dynamic system is the most optimal dynamic system amongst three types.
2015-09-29
Technical Paper
2015-01-2892
Carlos A. Pereira, Max Morton, Claire Martin, Geert-Jan Schellekens
The current trend towards energy efficient commercial vehicles requires a substantial improvement in their aerodynamic performance. The two largest contributions to the drag of a tractor-trailer combination are the wake at the rear of the trailer and the turbulent in-flow at the trailer gap. By integrating into the design of the roof fairing ducts that divert and speed-up air flow it is possible to obtain a reduction of drag in the trailer gap and alter the trailer wake favorably. The resulting decrease in yaw-averaged overall drag coefficient is of 5.8%. This translates into an improvement in fuel efficiency of 3% when compared to the baseline . The design optimization was performed using parametric variation of a computational fluid dynamic model at zero and six degree yaw.
2015-09-29
Technical Paper
2015-01-2833
Ashley L. Dunn, Brian Boggess, Nicholas Eiselstein, Michael Dorohoff, Harold Ralston
Brake chamber construction allows for a finite stroke for pushrods during brake application. As such, the Federal Motor Carrier Safety Regulations (FMCSRs) mandate maximum allowable strokes for the various chamber types and sizing. Brake strokes are often measured during compliance inspections and post-accident investigations in order to assess vehicle braking performance and/or capability. A number of forensic studies have been performed, and their results published, regarding the effect of brake stroke on braking force and heavy truck stopping performance. All of the studies have relied on a brake supply pressure in the neighborhood of 100 pounds per square inch (psi). When brake strokes are measured in the field, following the Commercial Vehicle Safety Alliance (CVSA) procedure, the application pressure is prescribed to be maintained between 90 and 100 psi.
2015-09-29
Technical Paper
2015-01-2855
Massimiliano Ruggeri, Giorgio Massarotti, Pietro Marani, Carlo Ferraresi
In recent years many studies were performed with the aim of reducing losses and to optimize the oil flow management in complex machines like excavators. One of the most promising ideas is the pump switch, due to the flexibility of switching one or more pumps to serve one actuator, as a function of oil flow request and machine mode. These studies were basically developed in MAHA fluid power center in US and are based on a distribution manifold were hydrostatic transmissions are applied to the different loads. The system presented couples more actuators to every single pumps and offers also cross connections, in order to increase systems flexibility in flow management.
2015-09-29
Technical Paper
2015-01-2872
Massimiliano Ruggeri, Andrea Cervesato, Carlo Ferraresi
Performance requests and machine automation, in conjunction with new regulations for agriculture, earthmoving and construction machines, represent today the most difficult challenge for machine designers and researchers. Machine control systems complexity and functional safety regulation compliance, are the most complex requirements to deal with in new machines design. The paper describes a steering system design, of a 6 wheels agricultural front articulated self-propelled machine, that must comply with new regulations in terms of functional safety. The vehicle steering is driven by an electro-hydraulic system, totally controlled using by wire electronics; the rear wheels are independently steering and controlled. This architecture requires a too high functional safety performance level.
2015-09-29
Technical Paper
2015-01-2884
Sam Waltzer, Julie Hawkins, Arvon Mitcham, Angus Lock, Dennis W. Johnson
The use of devices to reduce aerodynamic drag on large trailers and save fuel in long-haul, over-the-road freight operations has spurred innovation and prompted some trucking fleets to use them in combinations to achieve even greater gains in fuel-efficiency. This paper examines aerodynamic performance and potential fuel saving benefits of using trailer aerodynamic components in combinations based upon wind tunnel test data. Representations of SmartWay-verified trailer aerodynamic components were tested on a one-eighth scale model of a class 8 sleeper tractor and a fifty three foot, van trailer model. The open-jet wind tunnel employed a rolling floor to reduce floor boundary layer interference. The drag impacts of aerodynamic packages are evaluated for both van and refrigerated trailers. Additionally, the interactions between individual aerodynamic devices is investigated.
2015-09-29
Technical Paper
2015-01-2902
Songzhi Yang, Dong Wang, Yan Dang, Liguang Li
Based on the real driving condition, this paper investigated the underhood flow field and temperature distribution of a heavy commercial vehicle by utilizing CFD commercial code FLUENT. To guarantee the authenticity of simulation , three kinds of driving conditions namely idling,peak torque, rated power were considered ,detailed computational model including front bumper, grill, cabin, all the underhood and underbody components, taking into account all heat transfer phenomenon including conduction, convection ,radiation in the engine compartment. By analyzing the velocity contour in different sections, underhood temperature field distribution and inlet temperature of condenser, intercooler and radiator, we found that serious air-recirculation existed in engine compartment under idling and peak torque conditions and the temperature of some components have exceeded its normal range in peak torque condition.
2015-09-29
Technical Paper
2015-01-2733
Samraj Benedicts, Vivek Seshan
This paper is a study of reaction forces and its effects on the chassis due to rear idler position. Rubber Track layouts and traction have been focus of most research work, here we study the effect of Rear Idler position on layout and chassis structure through simulated analysis. An agriculture paddy combine harvester with rubber track is considered for the purpose of this work. Firstly the complete undercarriage is modeled in 3D using Creo and exported to Pro Mechanica for simulation. The real time forces, constraints were applied and the results were correlated to actual field results. The simulations were optimized through several iterations to match the field test results. The simulation and field test results show good agreement to the forces and constrains applied for simulation. Secondly the model was simplified for relative analysis and simulated for different rear idler positions with alternate tensioning methods.
2015-09-29
Technical Paper
2015-01-2786
Andrei Keller, Sergei Viktorovich Aliukov
In the present paper, it has been done study of different methods of power distribution among the drive wheels of a all-wheel-drive truck, namely: method of periodical action; method of partial solution; method of limit of excessive action; and method of introducing a rigid kinematic connection. Assessment how these methods influence on the performance characteristics of a multi-purpose vehicle has been done. For implementation of the method of periodical action the appropriateness of switching off some of the driving axles is justified. For implementation of the method of partial solution it is developed method of measuring of rational gear ratio of center differential providing the required level of performance of the all-wheel drive truck.
2015-09-29
Technical Paper
2015-01-2751
Igor Baseski, Kenneth Norman, David Ryan, Stefanie Stahara
At the request of the U.S. Army’s Tank Automotive Command (TACOM) laboratory facilities have been built to measure the suspension and mass parameters of the U.S. Army and civilian wheeled vehicles. This is part of an ongoing effort to model and predict vehicle dynamic behavior, so as to build vehicles that are less prone to roll over, have better handling stability, and perform better in rough terrain. These new machines, called the Suspension Parameter Identification and Evaluation Rig (SPIdER) and Vehicle Inertial Properties Evaluation Rig (VIPER), are part of a set of large test devices at TACOM’s facility in Warren, MI. The SPIdER machine operates by holding the vehicle body fixed using a variety of clamps and chains that are arranged specifically for each vehicle. Hydraulic cylinders are used to move an “axle frame” in bounce or roll under each axle being tested. Combinations of bounce and roll can be used, which could be used to simulate roll under different loading conditions.
2015-09-29
Technical Paper
2015-01-2721
Balaji Lomada, R. Jayaganthan, V. Vijaykumar
Commercial vehicle industry is presently striving towards development of buses with enhanced passenger safety and comfort. This calls for additional components and aggregates that eventually lead to increase in the overall length of the bus. Usually, steering system of longer wheel base and longer front overhang (FOH) vehicles have multiple linkages such as bevel box or relay arrangement instead of direct draglink because of packaging and design constraints. In this work, an attempt has been made to design the steering system for longer FOH vehicles with direct draglink arrangement. Here, single draglink is packaged and designed with high strength tube material (Yield stress is Min. 700 MPa) by optimising the steering geometry. Design optimisation of steering geometry is carried out ensuring existing level steering performance without compromising vehicle dynamic parameters. The CAE-MBD analysis has been done to compare the performance of existing and proposed steering system.
2015-09-29
Technical Paper
2015-01-2868
John Woodrooffe, Daniel Blower
This paper examines truck driver injury and loss of life in truck crashes related to cab crashworthiness and investigate regulations and industry trends in relation to truck occupant protection. The paper provides analysis of truck driver casualties in crashes to provide a better understanding of injury mechanisms and to review regulatory and industry initiatives concerned with reducing the number of truck occupant fatalities and the severity of injuries. The commercial vehicle focus is on truck-tractors and single unit vehicles in the NHTSA Class 7 & 8 weight range. The study used UMTRI's Trucks Involved in Fatal Accidents (TIFA) survey file and NHTSA's General Estimates System (GES) file for categorical analysis and the Large Truck Crash Causation Study (LTCCS) for a supplemental clinical review of cab performance in frontal and rollover crash types.
2015-09-29
Technical Paper
2015-01-2863
Yogesh Sharma, Rohit Kumar Garg, Rishabh Raj Bhargava, Aadityeshwar Saran Singh Deo, Aditya Krishna, Shubham Garg, Rahul Mehendiratta, Ankit Goila
ABSTRACT
2015-09-29
Technical Paper
2015-01-2842
Hongyu Zheng, Jinghuan Hu, Shenao Ma
By reviewing the previous research, we put the stability of tractor trailer into two categories, roll stability and yaw stability, and identify the indicators of two kinds of stability. Further we came up with three normal stability loss situations. They are roll-over, jack-knife and trailer swing. This work extends previous tractor trailer stability research from roll stability to roll/yaw stability; moreover, we set up the object of our investigation, that is enhance the tractor-trailer stability by reducing the occurrence of three stability loss. Based on the tractor semi-trailer model built in MATLAB, we made research on how the vehicle parameters affect the entire vehicle dynamic stability. In this section, we modified the model by changing a more sophisticated tire model. This work will benefit the commercial vehicle designer in the early stage of vehicle designing.
2015-09-29
Technical Paper
2015-01-2736
T.E. Harikrishna, P Murali, M Mufti
Vehicle handling is an important attribute that is directly related to vehicle safety. The rapid development of road infrastructure has resulted in a greater focus on safety and stability. Commercial vehicle stability and safety assumes higher significance because of high center of gravity (CG) and heavier loads. A gamut of parameters influence vehicle handling directly and indirectly. However, it is quite difficult to gauge through physical testing, the extent of each parameter’s influence on handling. Therefore, this paper examines vehicle handling by way of a sensitivity analysis through numerical simulation. A prototype vehicle is also instrumented and tested to confirm and validate the results of the suspension.
2015-09-29
Technical Paper
2015-01-2835
Sughosh J. Rao, Mohamed Kamel Salaani, Devin Elsasser, Frank Barickman, Joshua L. Every, Dennis A. Guenther
This study was performed to showcase the possible applications of the Hardware in the Loop (HIL) simulation environment developed at The National Highway Traffic Safety Administration (NHTSA) Vehicle Research and Test Center (VRTC) research lab, to test heavy truck Electronic Stability Control (ESC) systems. In this study, the HIL simulation environment was used to recreate (an interpretation of) an actual accident scenario involving a single tractor-trailer. The scenario was then simulated with and without an ESC system to investigate the advantages afforded by the ESC system, if any. An acutal crash scenario reported in the Large Truck Crash Causation Survey (LTCCS), involving a single tractor-trailer was chosen. The crash scenario was interpretted as a path following problem and three possible driver intended paths were developed from the accident scene data. A path following algorithm was implemented in Simulink to simulate these paths.
2015-09-29
Technical Paper
2015-01-2839
Rangaraj Ramanan Durai, Ashok Thirupathi, Mohith Krishna Shetty, Dilip Joy Mampilly
In this paper Longitudinal Force Slip (LFS) controller will be designed for controlling the traction force in each wheel when Rock Crawl Scenario prevails for commercial vehicles working in Off-Road condition. During Rock crawling the wheels can have more longitudinal slip than lateral slip. Slip is caused by relative movement of tires with the rock. PI controller (Longitudinal Force Controller) will be designed in order to stabilize the traction force on individual wheels. Individual Lateral and Longitudinal force will be calculated for each wheel from Tire modeling. Optimal longitudinal force will be determined based on fuzzy model with the help of determined Mue. The designed LFS controller which controls the individual traction force by applying active braking. Active braking on individual wheel will be realized with the hydraulic system associated with Vehicle Stability Control ECU (VSC - ECU). Optimal engine torque will be calculated based on driver pedal request.
2015-09-29
Technical Paper
2015-01-2873
Sumit Sharma, Sandeep Sharma, Sanjay Tiwari, Umashanker Gupta
Years ago the main purpose of heavy duty truck is to carrying the loads, in the current scenario cabin comfort and safety is also equally important. With the improved infrastructure quality the average speed of these types of vehicle has also been increased. With the higher average speed, the chances of getting crash have also been increased. In order to provide safety to the driver, all the safety parameters should be considered in advance at the time of design and development of cabin. Sufficient survival space must be present at the time of crash. In order to provide optimum ride comfort, fully suspended cab was designed. The main aim of this study is to develop detailed 3D finite element (FE) model of fully suspended heavy duty truck cabin with detailed suspensions system and simulate crash test scenario presented in regulation ECE-R29 using LS-Dyna explicit solver.
2015-09-29
Technical Paper
2015-01-2869
Sumit Sharma, Sandeep Sharma, Umashanker Gupta, Ravi Joshi, Shailesh Pawar
Buses are one of the main and favorite sources of public transit in India. Thousands of people die or injure severely every year due to Bus accidents. Passenger injury in Bus accidents can be due to high stiff seat structures. Most of the occupants seated in the second row or further back were injured by hitting the seat back in the row in front of them. AIS023 (AUTOMOTIVE INDUSTRY STANDARDS) is one of the several mandatory standards from CMVR (CENTRAL MOTOR VEHICLES RULES) to ensure the safety during crash. As per AIS-023 passenger seat of bus should not cause injury because of high stiffness, on the other hand seat should also be able to carry the passenger force during accidents. With this mechanism AIS023 specifies minimum and maximum range deformations of seat back to minimize the passenger injury. This study includes the FE (Finite Element) analysis and design of Bus seat as per AIS023 test setup with LS-Dyna explicit tool.
2015-09-29
Journal Article
2015-01-2846
Chunshan Li, Guoying Chen, Changfu Zong, Wenchao Liu
This paper presents a fault-tolerant control (FTC) algorithm for four-wheel independently driven and steered (4WID/4WIS) electric vehicles. The Unscented Kalman Filter (UKF) algorithm is utilized in the fault detection and diagnosis (FDD) module so as to estimate the in-wheel motor parameters, which could diagnose parameters variations caused by in-wheel motor fault. A sliding mode controller (SMC) is able to compute the generalized forces/moments to follow the desired vehicle motion. By considering the tire adhesive limits, a reconfigurable control allocator optimally distributes the generalized forces/moment among healthy actuators so as to minimize the tire workloads once the actuator fault is detected. An actuator controller calculates the driving torques of the in-wheel motors and steering angles of the wheels in order to finally achieve the distributed tire forces. If one or more in-wheel motors lose efficacy, the FDD module diagnoses the actuator failures first.
Viewing 1 to 30 of 18629