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Viewing 1 to 30 of 7999
2017-01-10
Technical Paper
2017-26-0340
Sarang Bire, Prashant R Pawar, M Saraf
Air suspension systems been used specially in buses and trucks since the 1950s. Now a days these systems are used as a standard fitment and widely used to improve the ride comfort, handling stability and also serves as a medium for better cargo protection, with its feasibility of adjusting height and spring pressure according to the driving conditions and loading scenario as per driver's intent. These system are very well developed for Trucks and buses and have feasibility for adapting for wide range of configuration of suspension system and axle. At same time development of air suspension system for different category of vehicle other than this such as SUV or pickup trucks is not accelerated to extent expected. This work describe realistic approach for development of air suspension for pickup category of vehicle which takes into consideration integrated approach of on road testing and virtual MBD tools.
2017-01-10
Technical Paper
2017-26-0344
Kartheek Nedunuri, Vivekanand Patnaik, Santosh Lalasure, K. Rajakumar, Rajiv Modi
A 4 wheeled vehicle with X-split brake configuration, in hydraulic circuit failed condition will have a behavior of induced sway due to braking force variation in the front and rear. This paper proposes a novel approach & methodology to predict the effect of brake force distribution variation on the vehicle swaying behavior during circuit failed braking condition. This Study will quantify vehicle sway, caused due to imbalance in brake force distribution during a circuit failed braking event on X Split configuration vehicles. It briefly discusses on a case study about most feasible solution to reduce the vehicle sway by altering the brake force distribution in circuit failed condition alone, without having any change in brake force distribution during service brake condition. It also provides a positive correlation & confirmation through actual vehicle testing.
2016-11-08
Technical Paper
2016-32-0025
Govardan Daggupati, Bapanna Dora Karedla, Chandan Bansilal Chavan, Gagandeep Singh Risam
Abstract In two wheelers the front suspension system is mounted on chassis by two steering bearings which are lubricated ball type angular contact bearings with significant radial force components. These bearings are designed to withstand maximum vehicle loads for target durability. Maximum load carrying capacity depends on the number and size of the balls, bearing size and material. For target durability with designed load carrying capacity, the ball contact pressure, bearing preload plays a major role as compared to other design parameters. Geometry parameters and maximum load defines contact pressure for given bearing design. But in two wheelers due to nature of usage and road conditions, the peak loads are dynamic and geometry based design calculations may not yield the most optimal bearing design. In this work the bearing ball race profile design is optimized by using dynamic bearing contact profiles by using nonlinear Finite Element Analysis.
2016-11-08
Technical Paper
2016-32-0054
Barath Mohan, KVM Raju, Sai Praveen Velagapudi, Chandramouli Padmanabhan
The aim of the present study is to develop feasible test methods to measure the lateral force characteristics of motorcycle tires. In this work, new experimental procedures are developed to estimate the lateral friction coefficient and lateral stiffness characteristics of motorcycle tires. A fairly accurate tire model is developed using the measured lateral force characteristics. Based on this tire model, the steer behavior and the cornering limits of the motorcycle are estimated using an analytical model of the vehicle. The results are validated with experimental data. The test methods proposed are shown to be adequate to estimate tire characteristics that are important for tire development and is less expensive compared to the standard testing facilities available.
2016-11-08
Technical Paper
2016-32-0053
Hisato Tokunaga, Kazuhiro Ichikawa, Takumi Kawasaki, Akiyuki Yamasaki, Tatsuo Ichige, Tomoyuki Ishimori, Yoichi Sansho
Abstract Owing to the recent developments in sensors with reduced size and weight, it is now possible to install sensors on a body of a motorcycle to monitor its behavior during running. The analysis of maneuverability and stability has been performed based on the data resulted from measurements by these sensors. The tire forces and moments is an important measurement item in maneuverability and stability studies. However, the tire forces and moments is difficult to measure directly, therefore, it is a common practice to measure the force and the moment acting on the center of the wheel. The measuring device is called a wheel forces and moments sensor, and it is widely used for cars. The development of a wheel forces and moments sensor for motorcycles has difficulty particular to motorcycles. First, motorcycles run with their bodies largely banked, which restricts positioning the sensors.
2016-11-08
Journal Article
2016-32-0051
Keisuke Terada, Takayuki Sano, Kenichi Watanabe, Takashi Kaieda, Kazuhisa Takano
Abstract In recent years three-wheel camber vehicles, with two wheels in the front and a single rear wheel, have been growing in popularity. We call this kind of vehicle A “Leaning Multi Wheel category Vehicle” (hereinafter referred to as a “LMWV”). A LMWV has various characteristics, but one of them stands out in particular. When a LMWV is cornering, if one of the front wheels passes over a section of road surface with a low friction coefficient, there is very little disturbance to the vehicle’s behavior and can continue to be driven as normal. However, there has been no investigation into why these vehicles have this particular characteristic. Consequently, in this paper an investigation was carried out in order to determine the behavior of a LMWV in this situation. First, measurements were taken using an actual vehicle to confirm the situation described above.
2016-10-17
Technical Paper
2016-01-2233
Matthew C. Robinson, Nigel N. Clark
Abstract The free piston engine combined with a linear electric alternator has the potential to be a highly efficient converter from fossil fuel energy to electrical power. With only a single major moving part (the translating rod), mechanical friction is reduced compared to conventional crankshaft technology. Instead of crankshaft linkages, the motion of the translator is driven by the force balance between the engine cylinder, alternator, damping losses, and springs. Focusing primarily on mechanical springs, this paper explores the use of springs to increase engine speed and reduce cyclic variability. A numeric model has been constructed in MATLAB®/Simulink to represent the various subsystems, including the engine, alternator, and springs. Within the simulation is a controller that forces the engine to operate at a constant compression ratio by affecting the alternator load.
2016-09-27
Technical Paper
2016-01-8044
Guoyu Feng, Wenku Shi, Henghai Zhang, Qinghua Zu
Abstract In order to predict the fatigue life of thrust rod heavy duty commercial vehicle balanced suspension, based on the continuum mechanics theory, the fatigue life prediction model of rubber with equivalent effect as damage parameter is established. Based on the equivalent stress and fatigue cumulative damage theory, the fatigue damage evolution equation of rubber material expressed by stress is derived by using the strain energy function. The general fatigue life model is established by using the maximum logarithmic principal strain as the damage parameter. The finite element model of the thrust rod is established, and the stress distribution of the spherical hinge rubber layer and the easy damage area are analyzed. Based on the equivalent stress calculation results and the axial tension stress and strain data of the rubber material, the accuracy of the results of the finite element calculation is verified.
2016-09-27
Technical Paper
2016-01-8028
Chao Yang, Nan Xu, Konghui Guo
Abstract This paper focuses on the modeling process of incorporating inflation pressure into the UniTire model for pure cornering. Via observing and manipulating the tire experimental data, the effects of inflation pressure on the tire cornering property are analyzed in detail, including the impacts on cornering stiffness, the peak friction coefficient, the curvature of transition region and the pneumatic trail. And the brief mechanism explanations are also given for some of these impacts. The results show that some effects of inflation pressure are similar to that of vertical load on the non-dimensional tire cornering property, and there are strong interactive effects between the two operating conditions. Therefore, in order to obtain concise expressions, the inflation pressure is incorporated into the UniTire tire model by analogy with the expressions for vertical load, and the interactive effects are also taken into account.
2016-09-27
Technical Paper
2016-01-8027
Stefan Steidel, Thomas Halfmann, Manfred Baecker, Axel Gallrein
Abstract Rolling resistance and tread wear of tires do particularly influence the maintenance costs of commercial vehicles. Although tire labeling is established in Europe, it is meanwhile well-known that, due to the respective test procedures, these labels do not hold in realistic application scenarios in the field. This circumstance arises from the development phase of tires, where the respective performance properties are mainly evaluated in tire/wheel standalone scenarios in which the wide range of usage variability of commercial vehicles cannot be considered adequately. Within this article we address a method to predict indicators for rolling resistance and tread wear of tires in realistic application scenarios considering application-based factors of influence like specific customers, operation circumstances, regional dependencies, fleet specific characteristics etc.
2016-09-27
Technical Paper
2016-01-8032
Anatoliy Dubrovskiy, Sergei Aliukov, Andrei Keller, Sergei Dubrovskiy, Alexander Alyukov
Abstract In this paper we consider a new design of adaptive suspension systems of vehicles with better technical characteristics and functional abilities in comparison with existing designs. We have developed the following main suspension components of vehicles: a lockable adaptive shock absorber with a wide range of control performance, implementing "lockout" mode by means of blocking adaptive shock absorber, and an elastic element with progressive non-linear characteristic and automatic optimization of localization of work areas. Advantages of our developments in the vehicle suspensions are the following: 1) when the vehicle is in a wide range of speeds in a so-called "comfort zone", we have managed, by applying the non-linear elastic element, to reduce significantly the stiffness of the elastic suspension elements in compare with the regular structures - at least in two times.
2016-09-27
Technical Paper
2016-01-8034
Hao Sun, Guoying Chen
Abstract Distributed steering vehicle uses four steering motors to achieve four wheel independent steering. The steering angle of each wheel can be distributed respectively. The tire cornering characteristics are added to traditional steering model to study the angle allocation control algorithm. Using the constraint relation between tire slip angle, vehicle speed, yaw rate and front steering angle, and connecting with the ideal ackermann steering relationship, steering angle allocation of front wheel independent steering and four wheel independent steering is derived. Then simulated analysis is carried out to demonstrate the efficiency of the algorithm. Improvements in tire wear condition are determined by evaluating the optimization in tire lateral force, and the vehicle stability is determined by vehicle slip angle. The simulation results show that the angle allocation control algorithm has a good effect on improving tire wear condition and enhancing the stability of vehicle.
2016-09-27
Technical Paper
2016-01-8037
Nan Xu, Konghui Guo, Yiyang Yang
Abstract The tire mechanics characteristics are essential for analysis and control of vehicle dynamics. Basically, the effects of sideslip, longitudinal slip, camber angle and vertical load are able to be represented accurately by current existing tire models. However, the research of velocity effects for tire forces and moments are still insufficient. Some experiments have demonstrated that the tire properties actually vary with the traveling velocity especially when the force and moment are nearly saturated. This paper develops an enhanced brush tire model and the UniTire semi-physical model for tire forces and moments under different traveling velocities for raising need of advanced tire model. The primary effects of velocity on tire performances are the rubber friction distribution characteristics at the tire-road interface.
2016-09-27
Technical Paper
2016-01-8085
Yanjun Ren, Gangfeng Tan, Kangping Ji, Li Zhou, Ruobing Zhan
Abstract The hydraulic retarder is an auxiliary braking device generally equipped on commercial vehicles. Its oil temperature change influences the brake performance of hydraulic retarder. The Organic Rankine Cycle (ORC) is a good means to recover exhausted heat. Moreover, it can cool oil and stably control oil temperature with the help of heat absorption related with evaporation. Comprehensively considering the heat-producing characteristics of hydraulic retarder and the temperature control demand, the aimed boundary conditions are determined. Also the changing rules about the working medium flow rate are obtained. In this work, the heat-producing properties of hydraulic retarder under different conditions and the oil external circulating performance is firstly analyzed. By researching the system’s adaptation to the limiting conditions, the aimed temperature to control is prescribed.
2016-09-27
Technical Paper
2016-01-8112
Jorge Leon, Jose M. Garcia, Mario J. Acero, Andres Gonzalez, Geng Niu, Mahesh Krishnamurthy
Abstract In order to improve efficiency and increase the operation of electric vehicles, assistive energy regeneration systems can be used. A hydraulic energy recovery system is modeled to be used as a regenerative system for supplementing energy storage for a pure electric articulated passenger bus. In this study a pump/motor machine is modeled to transform kinetic energy into hydraulic energy during braking, to move the hydraulic fluid from the low pressure reservoir to the hydraulic accumulator. The simulation of the proposed system was used to estimate battery savings. It was found that on average, approximately 39% of the battery charge can be saved when using a real bus driving cycle.
2016-09-27
Technical Paper
2016-01-8121
Riccardo Bianchi, Addison Alexander, Andrea Vacca
Abstract Typically, earthmoving machines do not have wheel suspensions. This lack of components often causes uncomfortable driving, and in some cases reduces machine productivity and safety. Several solutions to this problem have been proposed in the last decades, and particularly successful is the passive solution based on the introduction of accumulators in the hydraulic circuit connecting the machine boom. The extra capacitance effect created by the accumulator causes a magnification of the boom oscillations, in such a way that these oscillations counter-react the machine oscillation caused by the driving on uneven ground. This principle of counter-reacting machine oscillations through the boom motion can be achieved also with electro-hydraulic solutions, properly actuating the flow supply to the boom actuators on the basis of a feedback sensors and a proper control strategy.
2016-09-27
Technical Paper
2016-01-8119
Jun Sun, Xiaofei Pei, Xuexun Guo, Yanqiang Zhao
Abstract In order to overcome hysteresis and dead zone problems caused by friction for the proportional solenoid valve, and improve rapidity and stability of the pneumatic system on hydraulic retarder, a closed-loop control strategy based on valve coil current was proposed. The high-frequency low-amplitude dither signal was introduced into the proportional solenoid valve. With the proper dither signal, the stick-slip motion of the valve core was transformed into a steady one, and its dynamic performance was improved. Consequently, response time of retarder was reduced during gear changing. The proportional valve coil current was measured as a feedback for a closed-loop control strategy. Combining with the closed-loop strategy, the PI control algorithm was adopted to make sure that valve current was in accordance with the target value. Pulse Width Modulation (PWM) signal was used for the driving of proportional solenoid valve.
2016-09-27
Technical Paper
2016-01-8012
Daniel E. Williams, Amine Nhila, Kenneth Sherwin
Abstract A large percentage of commercial vehicles transport freight on our interstate highway system. These vehicles spend the vast majority of their duty cycle at high speed maintaining a lane. As steering is integrated into ADAS, objective performance measures of this most common mode of commercial vehicle operation will be required. Unfortunately in the past this predominant portion of the commercial vehicle duty cycle was overlooked in evaluating vehicle handling. This lanekeeping mode of operation is also an important, although less significant portion of the light vehicle duty cycle. Historically on-center handling was compromised to achieve acceptable low speed efforts. With the advent of advanced active steering systems, this compromise can be relaxed. Objective measures of lanekeeping are developed and performance of various advanced steering systems is quantified in this important operating mode.
2016-09-27
Technical Paper
2016-01-8006
John Reid, Stewart Moorehead, Alex Foessel, Julian Sanchez
Abstract A transformation of agriculture reached commercial reality at the beginning of this century as automated steering of agricultural machine systems increased the productivity and convenience in crop production systems. Following guidance, additional technologies have resulted in increasing optimized machine productivity. Today, integrated worksite solutions through machine and information management continues to transform agriculture. This is the precursor to autonomous worksite solutions that lead to the optimization of the worksite ecosystem. This paper will review the progress from the perspective of the customer value provided by increasing automated systems and the industry execution of autonomous driving technologies and will enable the pathways to autonomous worksites.
2016-09-27
Technical Paper
2016-01-8033
Guoying Chen
Abstract According to the vehicle’s driving conditions, electronically controlled air suspension (ECAS) systems can actively adjust the height of vehicle body, so that better ride comfort and handling stability will be achieved, which can’t be realized by traditional passive suspension. This paper presents a design and implementation of ECAS controller for vehicle. The controller is aimed at adjusting the static and dynamic height of the vehicle. To exactly track the height of the vehicle and satisfy the control demand of air suspension, a height sensor decoding circuit based on the inductance sensor is designed. Based on it, a new height control algorithm is adopted to achieve rapid and precise control of vehicle height. To verify the function of the designed controller and the proposed height control algorithm, an air spring loading test bench and an ECU-in-loop simulation test bench are respectively established.
2016-09-27
Technical Paper
2016-01-8114
Massimiliano Ruggeri, Pietro Marani, Michele Selvatici
Abstract Stationary (parking) brake is a very important and safety critical function in many classes of machines. The new transmissions and the “by wire” systems increase the criticality of the role of stationary brake, as it is also an emergency (secondary) brake, and it’s often used to hold the vehicle when the transmission is not locking the wheels. As an example, dual clutch and power-shift transmission gear systems, as well as hydrostatic transmissions under certain circumstances, are often unable to hold the vehicle stopped and this function is provided by the stationary brake. Due to the main need of having the brake actuated when vehicle is stopped, without any hydraulic and electric power, the brake configuration is normally a “negative” configuration, usually called “spring applied” because of the actuator configuration, but this configuration causes the brake actuation when de-energized, even in case of system failure.
2016-09-27
Technical Paper
2016-01-8102
Rıfat Kohen Yanarocak, Yavuz Can Ozkaptan
Abstract The intake and exhaust valve spring of a 12.7L heavy duty diesel engine was instrumented with torque/shear rosette type strain gages to measure torsional stresses applied on the springs under different engine operating conditions. The engine was tested with no load, partial load and full load conditions and the effect of engine brake switch loading operation on the springs is investigated. Additional measurement of the valve lift motion and the peak fire pressure values from exactly the same cylinder were conducted to better understand the exact timing of the forces applied on the spring. This study gave an insight to the design engineer to determine the dynamic safety margin of the spring under permissible torsional stress values and optimize the material type of the spring accordingly. Another achievement is to measure any possible unpredictable torsional stress values occurred during engine operation when the engine brake is turned on/off and correlate the CAE model.
2016-09-27
Technical Paper
2016-01-8042
Danna Jiang, Ying Huang, Xiaoyi Song, Dechun Fu, Zhiquan Fu
Abstract This paper describes a uniform Hardware-In-the-Loop (HiL) test rig for the different types of Electronic Braking System (EBS). It is applied to both modular testing and integrated testing. This test rig includes a vehicle dynamic model, a real-time simulation platform, an actual brake circuit and the EBS system under test. Firstly, the vehicle dynamic model is a highly parameterized commercial vehicle model. So it can simulate different types of commercial vehicle by different parameter configurations. Secondly, multi-types of brake circuit are modeled using brake components simulation library. So, it can test the EBS control unit independently without the influence of any real electro-pneumatic components. And a software EBS controller is also modeled. So it can test the algorithm of EBS offline. Thirdly, all real electro-pneumatic components without real gas inputted are connected to the real-time test platform through independent program-controlled relay-switches.
2016-09-27
Technical Paper
2016-01-8038
Yunbo Hou, Yang Chen, Mehdi Ahmadian
Abstract This paper studies the effect of different longitudinal load conditions, roundabout cross-sectional geometry, and different semi-truck pneumatic suspension systems on roll stability in roundabouts, which have become more and more popular in urban settings. Roundabouts are commonly designed in their size and form to accommodate articulated heavy vehicles (AHVs) by evaluating such affects as off-tracking. However, the effect of the roadway geometry in roundabouts on the roll dynamics of semi-tractors and trailers are equally important, along with their entry and exit configuration. , Because the effect of the roundabout on the dynamics of trucks is further removed from the immediate issues considered by roadway planner, at times they are not given as much consideration as other roadway design factors.
2016-09-27
Technical Paper
2016-01-8079
Zhiwei Zhang, Gangfeng Tan, Mengying Yang, Zhongjie Yang, Mengzuo Han
Abstract The hydraulic retarder is an important auxiliary braking device. With merits such as its high braking torque, smooth braking, low noise, long service life and small size, it is widely used on modern commercial vehicles. Transmission fluid of traditional hydraulic retarder is cooled by engine cooling system, which exhausts the heat directly and need additional energy consumption for the thermal management component. On account of the working characteristics of hydraulic retarder, this study designs a set of waste heat recovery system based on the Organic Rankine Cycle (ORC). Under the premise of ensuring stable performance of hydraulic retarder, waste heat energy in transmission fluid is recycled to supplement energy requirements for cooling system. First of all, a principle model, which is scaled down according to D300 retarder`s thermal power generation ration of 1:100, is established.
2016-09-27
Technical Paper
2016-01-8031
Nicholas Atanasov, Evan Chenoweth
Abstract Since the introduction of electronically controlled air suspension (ECAS) systems in the nineties, no major improvements have been made in the realm of controlling air suspensions in the heavy duty truck market. Despite the lack of improvement, a need exists for intelligently controlled air suspension systems, specifically systems which can be applied to 6x2 axle configurations in the North American market. This study outlines a concept proposal for a novel suspension control concept which encompasses traction control capabilities in addition to suspension control for improved fuel efficiency benefit. The major novelty of the concept is that, by utilizing specific axle configurations and tires, a shift in pressure from the driven to the non-driven axles may result in improvements in the overall fuel economy of the vehicle.
2016-09-27
Journal Article
2016-01-8010
M. Kamel Salaani, David Mikesell, Chris Boday, Devin Elsasser
Abstract Field testing of Automatic Emergency Braking (AEB) systems using real actual heavy trucks and buses is unavoidably limited by the dangers and expenses inherent in crash-imminent scenarios. For this paper, a heavy vehicle is defined as having a gross vehicle weight rating (GVWR) that exceeds 4536 kg (10,000 lbs.). High fidelity Hardware-in-the-Loop (HiL) simulation systems have the potential to enable safe and accurate laboratory testing and evaluation of heavy vehicle AEB systems. This paper describes the setup and experimental validation of such a HiL simulation system. An instrumented Volvo tractor-trailer equipped with a Bendix Wingman Advanced System, including the FLR20 forward looking radar and AEB system, was put through a battery of different types of track tests to benchmark the AEB performance.
2016-09-27
Journal Article
2016-01-8029
Chrysostomos-Alexandros Bekakos, George Papazafeiropoulos, Dan J. O'Boy, Jan Prins, George Mavros
Abstract A novel semi-analytical solution has been developed for the calculation of the static and dynamic response of an off road tire interacting with a deformable terrain, which utilizes soil parameters independent of the size of the contact patch (size-independent). The models involved in the solution presented, can be categorized in rigid and/or pneumatic tires, with or without tread pattern. After a concise literature review of related methods, a detailed presentation of the semi-analytical solution is presented, along with assumptions and limitations. A flowchart is provided, showing the main steps of the numerical implementation, and various test cases have been examined, characterized in terms of vertical load, tire dimensions, soil properties, deformability of the tire, and tread pattern. It has been found that the proposed model can qualitatively capture the response of a rolling wheel on deformable terrain.
2016-09-27
Journal Article
2016-01-8104
Ryo Yamaguchi, Hiromichi Nozaki
Abstract In this study, we report on the development of a steering assistance control system that feeds back information on the outside environment collected by laser sensors to the vehicle driver. The system consists of an emergency avoidance assistance control program that performs obstacle detection and avoidance, as well as a cornering assistance control program that operates by detecting the white lines painted on roadways. Driving simulator experiments were conducted in order to confirm the effectiveness of these functions, as well as to improve understanding of the synergistic effects of the steering assistance and chassis control functions: camber angle control and derivative steering assistance (DSA) control.
2016-09-27
Journal Article
2016-01-8030
Dai Quoc Vo, Hormoz Marzbani, Mohammad Fard, Reza N. Jazar
Abstract As long as a tire steers about a titled kingpin pivot, the point coming in contact with the road moves along its perimeter. This movement affects the determination of kingpin moments caused by the tire forces, especially for large steering angles. The movement, however, has been neglected in the literature on the steerable-tire-kinematics-related topics. In this investigation, the homogeneous transformation is employed to develop a kinematic model of a steering tire in which the instantaneous ground-contact point on the tire is considered. The moments about the kingpin axis caused by tire forces are then computed based on the kinematics. A four-wheel-car model is constructed for determining the kingpin moment of steering system during the low-speed cornering maneuver. The result shows that the displacement of the ground-contact point along the tire perimeter is significant for large steering angles.
Viewing 1 to 30 of 7999