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2014-09-30
Technical Paper
2014-01-2282
Dhiraj Dashrat Salvi
Braking system is having a key importance in vehicle safety & handling stability. In this research paper I had developed a circuit model of Antilock braking system where the operating medium is hydro-pneumatic. A solenoid operated modulator valve consisting of two 2/2 valves is connected in line with the air cylinder & hydraulic master cylinder assembly. Using methodology of response time calibration time taken to modulate hydraulic pressure against pneumatic pressure is evaluated. The signal input to the modulator valve is given by the Electronic controlled unit (ECU). All results obtained is exported to an excel file using Data Acquisition software with pressure myograph system. It gives easy and intuitive readings based on the signal program from ECU for various inputs (i.e. ramp, step). The signals are program for various inputs in order to check the fidelity of the circuit. These readings are easily customized to get the optimum graphs.
2014-09-30
Technical Paper
2014-01-2287
Hongyu Zheng, Linlin Wang
Abstract A brake pad wear control algorithm used under non-emergency braking conditions is proposed to reduce the difference in brake pad wear between the front and rear axles caused by the difference in brakes and braking force. According to the adhesion state of the pad wear, the control algorithm adjusted the braking force distribution ratio of front and rear wheel that balanced adhesion pad wear value. Computer co-simulations of braking with Trucksim and Matlab/Simulink using vehicle models with equal brake pad wear, greater wear on the front axle and greater wear on the rear axle respectively is performed. The computation simulation results show that meet the brake force distribution system regulatory requirements and total vehicle braking force unchanged.
2014-09-30
Technical Paper
2014-01-2285
Dong Zhang, Changfu Zong, Ying Wan, Hongyu Zheng, Wei-qiang Zhao
Abstract Electronic braking system (EBS) of commercial vehicle is developed based on Anti-lock Braking System (ABS), for the purpose of enhancing the braking performance. Based on the previous study, this paper aims at the development and research on the control strategy of advanced electronic braking system for commercial vehicle, which mainly includes braking force distribution and multiple targets control strategy. In the study of braking force distribution control strategy, the mass of vehicle and the axle loads will be calculated dynamically and the braking force of each wheel will be distributed regarding to the axle loads. The braking intention recognition takes the brake pad wear into account when braking uncritically, so it can detect a difference in the pads between the front and the rear axles. The brake assist strategy supports the driver during emergency braking and the braking distance is shortened by the reduction of the braking system response time.
2014-09-30
Technical Paper
2014-01-2288
Boris Belousov, Tatiana I. Ksenevich, Vladimir Vantsevich, Sergei Naumov
An open-link locomotion module (OLLM) is an autonomous energy self-sufficient locomotion setup for designing ground wheeled vehicles of a given configuration that includes drive/driven and steered/non-steered wheels with individual suspension and brake systems. Off-road applications include both trucks and trailers. The paper concentrates on the module's electro-hydraulic suspension design and presents results of analytical and experimental studies of a trailer with four driven (no wheel torque applied) open-link locomotion modules. On highly non-even terrain, the suspension design provides the sprung mass with sufficient vibration protection at low level of normal oscillations, enhanced damping and stabilized angular movements. This is achieved by the introduction of two control loops: (i) a fast-acting loop to control the damping of the normal displacements; and (ii) a slow-acting control loop for varying the pressure and counter-pressure in the suspension system.
2014-09-30
Technical Paper
2014-01-2286
Ying Wan, Dong Zhang, Zhao Weiqiang, Changfu Zong, Jongchol Han
Pneumatic Electric Braking System (EBS) is getting widely spread for commercial vehicles. Pneumatic EBS improves the problem of slow response of traditional pneumatic braking system by implementing brake-by-wire. However, the time-delay response and hysteresis of some electro-pneumatic components and some other issues decrease the response and control accuracy of the pneumatic EBS.
2014-09-30
Technical Paper
2014-01-2310
Anatoliy Dubrovskiy, Sergei Aliukov, Yuriy Rozhdestvenskiy, Olesya Dubrovskaya, Sergei Dubrovskiy
Abstract We have developed a fundamentally new design of adaptive suspension systems of vehicles. Their technical characteristics and functional abilities are far better than the existing designs of suspensions. We have developed the following main suspension components of vehicles: a lockable adaptive shock absorber with an ultra-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. Our patents confirm the novelty and efficiency of our major design decisions. Advantages of our developments in the vehicle suspensions are the following.
2014-09-30
Journal Article
2014-01-2292
Anudeep K. Bhoopalam, Corina Sandu, Saied Taheri
Abstract Safety and minimal transit time are vital during transportation of essential commodities and passengers, especially in winter conditions. Icy roads are the worst driving conditions with the least available friction, leaving valuable cargo and precious human lives at stake. The study investigates the available friction at the tire-ice interface due to changes in key operational parameters. Experimental analysis of tractive performance of tires on ice was carried out indoor, using the terramechanics rig located at the Advanced Vehicle Dynamics Laboratory (AVDL) at Virginia Tech. The friction-slip ratio curves obtained from indoor testing were inputted into TruckSIM, defining tire behavior for various ice scenarios and then simulating performance of trucks on ice. The shortcomings of simulations in considering the effects of all the operational parameters result in differences between findings of indoor testing and truck performance simulations.
2014-09-30
Technical Paper
2014-01-2291
Dong Zhang, Changfu Zong, Guoying Chen, Pan Song, Zexing Zhang
Abstract A full drive-by-wire electric vehicle, named Urban Future Electric Vehicle (UFEV) is developed, where the four wheels' traction and braking torques, four wheels' steering angles, and four active suspensions (in the future) are controlled independently. It is an ideal platform to realize the optimal vehicle dynamics, the marginal-stability and the energy-efficient control, it is also a platform for studying the advanced chassis control methods and their applications. A centralized control system of hierarchical structure for UFEV is proposed, which consist of Sensor Layer, Identification and Estimation Layer, Objective Control Layer, Forces and Motion Distribution Layer, Executive Layer. In the Identification and Estimation Layer, identification model is established by utilizing neural network algorithms to identify the driver characteristics. Vehicle state estimation and road identification of UFEV based on EKF and Fuzzy Logic Control methods is also conducted in this layer.
2014-09-30
Technical Paper
2014-01-2290
Guoying Chen, Dong Zhang
Abstract Four-wheel independent control electric vehicle is a new type of x-by-wire EV with four wheels independent steering and four wheels independent drive/brake systems. In order to take full advantage of the vehicle's performance potential, this paper presents a novel integrated chassis control strategy. In the paper, the strategy is designed by the hierarchical control structure and divided into integrated control layer and allocation layer. By this method, the control logical can be modularized and simplified. In the integrated control layer, Model Prediction Control (MPC) is adopted to design the integrated control unit, which belongs to be a kind of local optimization algorithm with feedback correction features. Using this method could avoid the system performance degradation caused by the control model mismatch. The control allocation layer is to optimally distribute the vehicle control forces to the steering/driving/brake actuators on each wheel.
2014-09-30
Technical Paper
2014-01-2299
Sijing Guo, Zhenfu Chen, Xuexun Guo, Quan Zhou, Jie Zhang
Abstract To integrate the energy-recovery characteristic of the Hydraulic electromagnetic shock absorber (HESA) and the anti-roll characteristic and anti-pitch characteristic of Hydraulic Interconnected Suspension(HIS), a Hydraulic Interconnected Suspension system based on Hydraulic Electromagnetic Shock Absorber (HESA-HIS) is presented. HESA-HIS has three operating modes: energy-recovery priority mode, dynamic performance priority mode and energy-recovery and dynamic performance balance mode. The working principle of HESA-HIS in the three operating modes is introduced, a full vehicle model is built by using the software AMESim, and some simulation tests are conducted by using the vehicle model. The simulation results show that the system can effectively reduce the roll angle of the vehicle, while maintaining good ride performance. Fishhook test results show that the roll angle of the HESA-HIS vehicle is reduced by 80%, compared to the traditional vehicle.
2014-09-30
Technical Paper
2014-01-2297
Mehmet Bakir, Murat Siktas, Serter Atamer
Abstract In today's world, there are a prominent number of weight and cost reduction projects within the vehicle engineering development activities. Regarding this phenomenon, a complete optimization study is applied to a leaf spring assembly, which has 4 leaves and which is used in heavy duty trucks, by reducing the number of leaves down to 3 together with weight and cost reductions. At the first step of the project, the stiffness of the leaf spring is calculated with in-house software based on mathematical calculations using the thickness profile of the leaves. Then the results of these calculations are compared with non-linear elastic leaf spring calculations which are conducted with FEA. This elastic leaf spring finite element model is transferred into Multi-Body-Simulation (MBS) model in order to determine the forces acting on the leaf spring.
2014-09-30
Journal Article
2014-01-2408
Mehdi Ahmadian
The 2014 SAE Buckendale Lecture will address the past developments and challenges of electromechanical “smart” systems for improving commercial vehicles' functionality. Electromechanical systems combine traditional mechanical devices with electrical components to provide far higher degree of functionality and adaptability for improved vehicle performance. The significant advances in microprocessors and their widespread use in consumer products have promoted their implementation in various classes of vehicles, resulting in “smart” devices that can sense their operating environment and command an appropriate action for improved handling, stability, and comfort. The chassis and suspension application of electromechanical devices mostly relate to controllable suspensions and vehicle dynamic management systems, such as Electronic Stability Control.
2014-09-30
Technical Paper
2014-01-2409
C Venkatesan, R DeepaLakshmi
Abstract The automotive industry is constantly looking for new alternate material and cost is one of the major driving factors for selecting the right material. ABT is a safety critical part and care has to be taken while selecting the appropriate material. Polyamide (PA12) [1] is the commonly available material which is currently used for ABT applications. Availability and material cost is always a major concern for commercial vehicle industries. This paper presents the development of ABT with an alternative material which has superior heat resistance. Thermoplastic Elastomer Ether Ester Block Copolymer (TEEE) [3] materials were tried in place Polyamide 12 for many good reasons. The newly employed material has better elastic memory and improved resistance to battery acid, paints and solvents. It doesn't require plasticizer for extrusion process because of which it has got excellent long term flexibility and superior kink resistance over a period of time.
2014-09-30
Technical Paper
2014-01-2405
Jiaqi Xu, Bradley Thompson, Hwan-Sik Yoon
Abstract Hydraulic excavators perform numerous tasks in the construction and mining industry. Although ground grading is a common task, proper grading cannot easily be achieved. Grading requires an experienced operator to control the boom, arm, and bucket cylinders in a rapid and coordinated manner. Due to this reason, automated grade control is being considered as an effective alternative to conventional human-operated ground grading. In this paper, a path-planning method based on a 2D kinematic model and inverse kinematics is used to determine the desired trajectory of an excavator's boom, arm, and bucket cylinders. Then, the developed path planning method and PI control algorithms for the three cylinders are verified by a simple excavator model developed in Simulink®. The simulation results show that the automated grade control algorithm can grade level or with reduced operation time and error.
2014-09-30
Technical Paper
2014-01-2404
Naseem A. Daher, Monika Ivantysynova
Original equipment manufacturers and their customers are demanding more efficient, lighter, smaller, safer, and smarter systems across the entire product line. In the realm of automotive, agricultural, construction, and earth-moving equipment industries, an additional highly desired feature that has been steadily trending is the capability to offer remote and autonomous operation. With the previous requirements in mind, the authors have proposed and validated a new electrohydraulic steering technology that offers energy efficiency improvement, increased productivity, enhanced safety, and adaptability to operating conditions. In this paper, the authors investigate the new steering technology's capacity to support remote operation and demonstrate it on a compact wheel loader, which can be remotely controlled without an operator present behind the steering wheel. This result establishes the new steer-by-wire technology's capability to enable full autonomous operation as well.
2014-09-30
Standard
J2932_201409
This document provides test performance requirements for air disc brake actuators for service and combination service parking brake actuators with respect to function, durability and environmental performance when tested according to SAE J2902.
2014-09-30
WIP Standard
J3081
This document is written to address acceleration and deceleration contol issues related to Heavy Duty Trucks and Bueses greater than 10,000 GVW.
2014-09-28
Technical Paper
2014-01-2532
Lu Xiong, Bing Yuan, Xueling Guang, Songyun Xu
Abstract In this paper, by analyzing multiple electro-hydraulic brake system schemes in detail, the idea of dual-motor electro-hydraulic brake system is proposed. As a new solution, the dual-motor electro-hydraulic brake system can actively simulate pedal feel, make the most of pedal power (from the driver), and reduce the maximum power output of each active power source remarkably, which is a distinctive innovation compared to most current electro-hydraulic brake systems. Following the proposed concept, a general research thought and method is conceived, and then a dual-motor electro-hydraulic brake system is designed. Finally, the simulation model is set up in AMESim software and its feasibility is simulated and verified.
2014-09-28
Technical Paper
2014-01-2531
Mandeep Singh Walia, Magnus Karlsson, Lars Hakansson, Gaurav Chopra
Abstract An analysis method to study the potentials of recovering the brake energy from Volvo articulated haulers has been developed. The study has been carried out with purpose to find out how and where possible hybrid solutions can be used. The method is based on the mapping of the peak brake power, brake energy and engine energy. This method was developed using adequate signals collected on haulers at three different customer sites. A conceptual study was also carried out concerning the brake energy to understand the actual amount of brake energy that may be stored in an Energy storage system (ESS). The results indicate that the analysis method developed can map the brake energy generated and also provide an overview of the actual amount of brake energy that can be accumulated in an ESS. Hence, the method may also providing guidelines regarding the selection of an ESS for a particular work site.
2014-09-28
Technical Paper
2014-01-2535
Ning Pan, Liangyao Yu, Zhizhong Wang, Liangxu Ma, Jian Song, Yongsheng Zhang, Wenruo Wei
Abstract With the advantages of free from engine vacuum, wheel cylinder pressure decoupled from the brake pedal and can be regulated individually and precisely, the brake-by-wire system has a huge application potential in vehicles, especially in electric vehicles (EV) and hybrid electric vehicles (HEV). Electro-hydraulic Brake system is the first approach towards brake-by-wire technology. This paper proposed a new compact EHB, aiming at decreasing the size, volume and cost without compromise of performance. The main components of the proposed EHB are pedal simulator, motor pump, accumulator and eight solenoid valves. An authentic model of the EHB and other key components of the brake system were established based on the test data from the test bench. A control algorithm using Round-Robin scheduling was presented to regulate the fluid pressure. Some parameters of the components were discussed to research their effects on system performance.
2014-09-28
Technical Paper
2014-01-2534
Liangxu Ma, Liangyao Yu, Xuhui Liu, Zhizhong Wang, Ning Pan
Abstract The paper is focused on the research of the automotive magneto-rheological brake system whose braking force comes from the shear stress of magneto-rheological fluid under the condition of magnetic field. The MRF brake is designed for an electric passenger car to replace a conventional hydraulic disc-type brake. The braking torque of this system can be linearly adjusted by the current in just a few milliseconds with proper materials. Therefore this system has a quick response and precise control performance with a low hysteresis. Nowadays, most of the related research of MRF is about the construction of the prototype and the realization of the brake force. Main limitation of MRF brake lies in the braking torque cannot meet the actual needs and the power consumption may be too much if it is not well designed. The prototype introduced in the SAE Brake Colloquium-31nd Annual has been manufactured and assembled critically.
2014-09-28
Technical Paper
2014-01-2528
Dominic D. Scopacasa
Abstract This paper will discuss how different forms of producing supplemental vacuum have varying effects on overall vehicle efficiency. The once reliable source of vacuum from the engine is becoming increasingly scarce due to higher efficiencies from modern IC engines and the growing use of turbochargers. This need for supplemental vacuum has led to several solutions to support vacuum needs, particularly for supplying the booster for brake assist. Using simulated vehicle environments for the various forms of supplemental vacuum the behavior of each can be better understood. Using this simulated environment the actual power consumed by each method of supplemental vacuum production can be accurately measured over various drive cycles and conditions including engine speed and brake applications. Depending on the means of supplemental vacuum the respective energy consumption can be applied to a vehicle model to show the end effects of each solution on a number of levels.
2014-09-28
Technical Paper
2014-01-2530
Kyung-Jung Lee, Jae-Min Kwon, Jae Seung Cheon, Hyun-Sik Ahn
Abstract This paper proposes a design approach for the network configuration of brake-by-wire (BBW) systems using the FlexRay communication protocol. Owing to the absence of mechanical or hydraulic back-ups, the BBW system needs to be highly reliable and fault-tolerant. The FlexRay network is shown to be very effective for such requirements of BBW systems by using hardware in-the-loop simulation (HILS), which allows developing and testing various algorithms and faithfully reproduces the actual system. The FlexRay protocols are designed using the FIBEX configuration tool appropriately for the control of BBW systems, and they are analyzed using the FlexRay communication monitoring tool. The results of HILS illustrate that the braking performance of a controller area network (CAN)-based network and that of a FlexRay-based network for BBW systems are very similar, however, the FlexRay-based network system is more reliable and ensures better fault diagnosis by monitoring more variables.
2014-09-28
Technical Paper
2014-01-2529
Klaus Augsburg, Dzmitry Savitski, Lukas Heidrich, Valentin Ivanov
Abstract The presented research discusses the experimental procedure developed for testing of friction brake systems installed on the modern electric vehicles. Approach of combined experimental technique utilizing hardware-in-the-loop platform and brake dynamometer is introduced. As the case study, an influence of brake lining coefficient of friction fluctuations on the anti-lock brake system (ABS) performance is investigated. The ABS algorithm is represented by the direct slip control aimed to the precise tracking of reference slip ratio by means of electric and friction brake system. Vehicle prototype is represented by RWD electric vehicle with in-wheel motors. Results, representing the investigated phenomenon, are derived using the developed combined test bench. The achieved results give a basis for further extension of standard brake testing procedures.
2014-09-28
Technical Paper
2014-01-2542
Liang Zhou, Chuqi Su
Abstract Recovering the braking energy and reusing it can significantly improve the fuel economy of hybrid electric vehicles (HEVs).The battery ability of recovering electricity limits the improvement of the regenerative braking performance. As one way to solve this problem, the technology of brake-by-wire can be adopted in the HEVs to use the recovery dynamically. The use of high-power electrical equipment, such as electromechanical brake (EMB), is working in the form of brake-by-wire. Due to the nature of EMB, there exists an obvious coupling relationship between the energy flow and brake force distribution. In this paper, a brake force distribution controller is proposed in HEV with EMB, which can maximize braking energy recovery, compared with the conventional distribution control without EMB. Meanwhile, an energy flow strategy working with the distribution controller is designed, which is less limited to the performance of the battery.
2014-09-28
Technical Paper
2014-01-2541
Michael Herbert Putz, Christian Wunsch, Markus Schiffer, Jure Peternel
Abstract The electro-mechanical brake (EMB) of Vienna Engineering (VE) uses a highly non-linear mechanism to create the high pressing force of the pad. The advantage is that the pad moves very fast when the pad pressing force is low and moves slower with increasing pressing force. The normal force in EMBs is often controlled by observing mechanical deformation to conclude to stress or force, commonly using strain gauges. It causes costs of the gauge itself and attaching them to e.g. the caliper and a sensitive amplifier. The full gauge equipment goes into the safety-related brake control system. The faintest damage (e.g. stone impacts, heat) gets the vehicle to the repair shop making expensive replacement necessary. To avoid the costs of the force measurement in the safety related system VE took the electrical motor measurements from the very beginning of the brake development for EMB control.
2014-09-28
Technical Paper
2014-01-2537
Zhizhong Wang, Liangyao Yu, Yufeng Wang, Kaihui Wu, Ning Pan, Jian Song, Liangxu Ma
Abstract The four-wheel-independent Electro-hydraulic Braking system (4WI EHB) is a wet type Brake-by-Wire system for passenger vehicle and is suitable for electric vehicle (EV) and hybrid electric vehicle (HEV) to cooperate with regenerative braking. This paper gives a review on the design concepts of the 4WI EHB from the following three aspects. 1. Hydraulic architectures. 2. Design concepts of the brake actuator. 3. Installation of the components on the vehicle. Simulations and experiments are carried out to further explore the performance of hydraulic backup and implicit hardware redundancy (IHR). A method to integrate the IHR with hydraulic backup without increasing the total amount of valves is proposed, making the IHR cost and weight competitive. By reviewing various design concepts and analyzing their advantages and drawbacks, a cost and weight competitive design concept of the 4WI EHB with good fail-safe and fault-tolerant performance is proposed.
2014-09-28
Technical Paper
2014-01-2536
Alberto Boretti, Stefania Zanforlin
Abstract Real driving cycles are characterized by a sequence of accelerations, cruises, decelerations and engine idling. Recovering the braking energy is the most effective way to reduce the propulsive energy supply by the thermal engine. The fuel energy saving may be much larger than the propulsive energy saving because the ICE energy supply may be cut where the engine operates less efficiently and because the ICE can be made smaller. The present paper discusses the state of the art of hydro-pneumatic drivelines now becoming popular also for passenger cars and light duty vehicle applications permitting series and parallel hybrid operation. The papers presents the thermal engine operation when a passenger car fitted with the hydro-pneumatic hybrid driveline covers the hot new European driving cycle. From a reference fuel consumption of 4.71 liters/100 km with a traditional driveline, the fuel consumption reduces to 2.91 liters/100 km.
2014-09-28
Technical Paper
2014-01-2539
Dongmei Wu, Haitao Ding, Konghui Guo, Yong Sun, Yang Li
Abstract Four-wheel-drive electric vehicles (4WD Evs) utilize in-wheel electric motors and Electro-Hydraulic Braking system (EHB). Then, all wheels torque can be controlled independently, and the braking pressure can be controlled more accurately and more fast than conventional braking system. Because of these advantages, 4WD Evs have potential applications in control engineering. In this paper, the in-wheel electric motors and EHB are applied as actuators in the vehicle stability control system. Based on the Direct Yaw-moment Control (DYC), the optimized wheel force distribution is given, and the coordination control of the hydraulic braking and the motor braking torque is considered. Then the EHB hardware-in-the-loop test bench is established in order to verify the effectiveness of the vehicle stability control algorithm through experiments.
2014-09-28
Technical Paper
2014-01-2514
Prashant Mahale, Aziz Bohari, Raajha M P
Abstract Brake noise is an emerging concern in Indian Auto-industry; with brake squeal being the most evident form of brake NVH. Squeal noise generation attributes to many parameters including kinematics of braking parts during pressure application, structural dynamic behavior which in turn depends on coupling at resonant frequencies of different parts of a brake assembly, material of brake parts, operating clearances in the mating parts etc. The genesis of brake squeal lies in the generation of unstable frictional forces during braking event. These frictional forces induce uncontrolled amplification of brake parts vibration, which in turn tend to produce perceivable sound or noise. The magnitude this vibration induced squeal depends on co-efficient of friction, braking pressure, speed and temperature of friction material.
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