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Event
2014-12-10
Event
2014-12-10
New rounds of stringent nitrogen oxides (NOx) emissions reduction regulations in Europe (Euro 6c) and North America (CARB LEV III, EPA Tier 3) are driving the optimization of existing diesel exhaust aftertreatment systems. Urea - Selective Catalytic Reduction (SCR) systems are among the de-NOx technologies that have been successfully introduced in recent years. The new regulations are bringing a closer look to SCR de-NOx performance particularly during the cold start phase of the existing emissions certification cycles. This presentation will review some of the options under consideration to address cold start NOx emissions. Some of these approaches impose new and more severe requirements on the urea injection function – these are also reviewed as well as the response to these requirements by the injection system designers.
Event
2014-12-10
Training / Education
2014-10-23
The acquisition of test data is required throughout the product's life cycle - in prototype performance evaluation, reliability/durability testing, duty-cycle analysis, end of line testing, and service and aftermarket product areas. Both lab and on-road testing is needed for components, sub-systems and entire vehicles. As in-vehicle networks become increasingly more sophisticated in terms of the number of controllers, the speed at which they communicate, and the number of parameters available, they are a virtual goldmine for the test engineer. If the data is already available on the vehicle network, the engineer may only need to add any missing sensors (or possibly none at all).
Event
2014-10-20
This session focuses on engine combustion and flow diagnostic development and demonstration. Examples of diagnostics of interest include, but are not limited to: LIF, PLIF, absorption/emission spectroscopy, ion probes, pressure sensors, and extractive and exhaust gas composition sensors.
Technical Paper
2014-10-13
Chunshan Li, Guoying Chen, Changfu Zong
This paper presents a fault-tolerant control (FTC) approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles. An adaptive control-based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints ; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization. The FTC approach is based on the reconfigurable control allocation which reallocates the generalized forces/moments among healthy actuators once the actuator failures is detected.
Event
2014-10-06
Evolving demands on brake systems driven by hybrid and electric vehicle architectures are providing opportunity for new component and brake system configurations and a demand for greater integration of the brake control system with overall vehicle controls. This session offers new concepts and ideas for electrically powered and controlled brake calipers, improvements in control strategies and system safety considerations.
Event
2014-10-06
Evolving demands on brake systems driven by hybrid and electric vehicle architectures are providing opportunity for new component and brake system configurations and a demand for greater integration of the brake control system with overall vehicle controls. This session offers new concepts and ideas for electrically powered and controlled brake calipers, improvements in control strategies and system safety considerations.
Technical Paper
2014-09-28
Dongmei Wu, Haitao Ding, Konghui Guo, Yong Sun, Yang Li
With the promotion of electric vehicles, their stability control problem has become increasingly important. Four-wheel-drive electric vehicle can not only control the vehicle stability through hydraulic braking pressure regulation, but also through controlling the motor driving and braking force to generate yaw moment , which are different with the conventional vehicles. In addition, the hydraulic braking system of four-wheel-drive electric vehicle is Electro-Hydraulic Braking System (EHB), rather than the conventional hydraulic braking system. With EHB, the braking pressure in four wheel cylinders can be controlled independently and flexibly, rather than depending on the braking pedal. Besides, there are also several pressure sensors in EHB, which can supply the wheel cylinder pressure information, without the need for pressure estimation. As a result, the way to achieve stability control of four-wheel drive electric vehicle will be different with conventional vehicle. Currently, there are not many researches on the stability control of four-wheel-drive electric vehicle with EHB, and most of them are still at the stage of virtual simulation, lacking testing and applications in real system.
Technical Paper
2014-09-28
Michael Herbert Putz, Christian Wunsch, Markus Schiffer, Jure Peternel
With linear actuated brakes the actuation force (or actuation torque) rises linearly from 0 to the full actuation force at full braking, causing a very variable motor current. 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. This non-linear actuation means that the motor is always running at relatively constant load (although the pad pressing force changes highly), resulting in a motor that can be optimized for constant torque and constant rpm, reducing size and costs and increasing efficiency. 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.
Technical Paper
2014-09-28
Kyung-Jung Lee, Jae-Min Kwon, Jae Seung Cheon, Hyun-Sik Ahn
X-by-wire technology replaces mechanical connections with electrical signals, and is indispensable for realizing an intelligent vehicle. The technology has many advantages including reduction of parts, increase in design degree-of-freedom, and safety increase. Especially, the Brake-by-Wire (BBW) system consists of electromechanical actuators and communication networks, instead of conventional hydraulic or electrohydraulic devices, has emerged as a new and promising vehicular braking control scheme. It offers enhanced safety and comfort, cuts off cost associated with manufacturing and maintenance, and eliminates environmental concerns caused by hydraulic systems. The BBW system has recently invoked a lot of interest for both industry and academia worldwide. The FlexRay is an automotive network communications protocol built to be a deterministic, fault-tolerant bus system. It was developed by the FlexRay Consortium as a conjunction with the leading automotive manufacturers. The FlexRay is a new time-triggered communication system for high-performance in-vehicle applications.
Technical Paper
2014-09-28
Lu Xiong, Bing Yuan, Xueling Guang, Songyun Xu
At the very beginning part, a detailed analysis on current status of electro-hydraulic brake system is carried out. By analyzing 28 electro-hydraulic brake systems, the paper provides a brief summarization on structural components of typical electro-hydraulic brake systems from the perspective of main functional units. Then a more in-depth analysis is conducted on the key functional units, particularly on Active pressure-building unit and Pedal simulation unit. For instance, in terms of Active pressure-building unit, electro-hydraulic brake system schemes can be divided into two categories according to active power sources: one is pump + high-pressure accumulator, the other electric motor+ reducing mechanism. Then author employs MK C1, the latest electro-hydraulic brake system launched by Continental AG, to illustrate its structural components and working principle. In the second part, the idea of dual-motor electro-hydraulic brake system is proposed. As a new solution, dual-motor electro-hydraulic brake system can actively simulate pedal feeling and merge pedal power (from the driver ) into braking power at the same time, which is a distinctive innovation compared to most current electro-hydraulic brake systems.
Technical Paper
2014-09-28
Liangxu Ma, Liangyao Yu, Xuhui Liu, Zhizhong Wang, Ning Pan
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 a small-sized electric passenger car to replace a conventional hydraulic disc-type brake. The brake disk is immersed in the MRF whose yield stress changes as the applied magnetic field. The braking torque of this system can be linearly adjusted by the current in just a few milliseconds without the conventional vacuum booster. This system has a quick response and precise control performance with a low hysteresis. Besides, the system has adopted the original complicated structure to save space and cost. Nowadays, most of the related research of MRF is about the construction of the prototype and the realization of the brake force. However, due to a lack of optimal design and the understanding of MRF, the main research progress is only about the simulation and the braking effect of the prototype can hardly meet the requirement of the vehicle braking.
Technical Paper
2014-09-28
Alberto Boretti, Stefania Zanforlin
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 thermal engine energy supply may be cut where the engine operates less efficiently and because the thermal engine can be made smaller. The present paper discusses the state of the art of hydro-pneumatic driveline now becoming popular also for passenger cars and light duty vehicle applications.
Technical Paper
2014-09-28
Zhizhong Wang, Liangyao Yu, Yufeng Wang, Kaihui Wu, Ning Pan, Jian Song, Liangxu Ma
The Distributed Electro-hydraulic Braking System (DEHB) is a wet type brake-by-wire system for passenger vehicles, and is especially suitable for electric vehicles and hybrid electric vehicles. The basic DEHB comprises four independent brake actuators connected to four hydraulic brakes. The word ‘distributed’ refers to the distributed arrangement of the brake actuators on the vehicle. Each brake actuator comprises an electric motor to provide brake power, a mechanism to translate rotational motion of the motor shaft into translational motion of a piston. The piston moves back and forth in a cylinder under the control of the motor to push the brake fluid into the brake. In this way, braking pressure can be controlled by the motor. Like other brake-by-wire systems, brake pedal simulator and pedal sensors are also used in DEHB. Although the concept of DEHB traces back to 1990s, only a few research papers can be found. This paper gives a review and outlook on the design concepts of DEHB from the following three aspects. 1.
Technical Paper
2014-09-28
Ning Pan, Liangyao Yu, Zhizhong Wang, Liangxu Ma, Jian Song, Yongsheng Zhang, Wenruo Wei
With the purpose of individual wheel cylinder pressure regulation and independent of engine vacuum, Brake-by-wire (BBW) systems are suitable for electric vehicles and hybrid electric vehicles. BBW system has been developed in recent years. Electro-Hydraulic Brake (EHB) system is the first step towards BBW system. Various EHB systems have been proposed by researchers. A typical design includes a high pressure accumulator to supply pressure source and pulse width modulated (PWM) solenoid valves to regulate the brake pressure, such as the product of Bosch and Toyota. The electrically driven booster system uses motor to boost driver brake input, such as the system proposed by Mobis. Continental Teves proposed an EHB system with modified ESC hydraulic unit and electric vacuum pump. This paper proposes a new compact EHB system, arming at decreasing the size and cost without compromise of performance. There are there sections in this paper, the first section of which is system configuration and basic operation principles, the second section is the hydraulic pressure control algorithm to regulate the cylinder pressure, and the last section shows the simulation study to verify the performance of the new proposed EHB and its pressure control algorithm.
Technical Paper
2014-09-28
Liang Zhou, Chuqi Su
In this paper,a strategy for recovery of braking energy in HEV with EMB is proposed, which is less limited to the performance of the 42V vehicle power supply, compared with the conventional recycling strategy without EMB. In the traditional HEV with 42V vehicle power supply, recovery of braking energy is mainly recycled to the 42V battery, directly. As charging current is too large, or charging time is too long can damage the battery, 42V battery is difficult to recycle braking energy effectively ,especially in complex urban condition with vehicle braking frequently and rapidly. But in HEV with EMB,the recovery transfers to the motor of EMB directly, which is utilized dynamically in the process of vehicle braking. Excess electricity transfers to the energy storage unit if the generator is performing a voltage higher than the required voltage of EMB brake motor, otherwise, the energy storage unit to supplement electricity. The kinetic energy of the HEV turned into electrical energy to EMB timely,rather than being stored statically in this process.
Technical Paper
2014-09-28
Mandeep Singh Walia, Magnus Karlsson, Lars Hakansson, Gaurav Chopra
Mandeep Singh Walia An analysis method to study the potentials in recovering the brake energy from Volvo articulated haulers has been developed. The study is made 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. The 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 the Energy storage systems (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 the ESS, which can also guide in an effective selection of the ESS for a particular work site.
Technical Paper
2014-09-28
Klaus Augsburg, Dzmitry Savitski, Lukas Heidrich, Valentin Ivanov
The presented study discusses design of brakes and brake control system for all-wheel drive electric vehicle equipped with individually controlled in-wheel motors (IWM). Initial part of the paper is dedicated to the analysis of different packaging of wheel brakes to be mounted together with IWM in the wheel hub. Special attention is given to the implementation of perimeter brake setup. Parameterization and design of specific perimeter brake configuration is introduced. The second part of the paper introduces advanced strategies for brake blending and ABS control. The proposed strategy of blending control realizes brake force distribution targeting the increase of regenerative braking with taking into account the limitations placed by the IWM operation. The ABS architecture is based on the direct slip controller. Its functionality will be illustrated with different case studies investigating the ABS braking with electric motors and hydraulic brake system. The particular attention is also given to the valuation of the brake comfort.
Technical Paper
2014-09-28
Jongsung Kim, Chjhoon Jo, Yongsik Kwon, Jae Seung Cheon, Soung Jun Park, Gab Bae Jeon, Jaehun Shim
Electro-Mechanical Brake (EMB) is the brake system that is actuated by the electrical energy and the motor rotation. It has similar design with Electro-Mechanical Parking Brake (EPB). It uses the gear multiplication structure for the enough torque and screw/nut mechanism for changing rotational movement to linear. The differences with EPB are screw/nut and motor type and some specification of the inner parts because the needed performance of the service braking like braking time is much higher than EPB, and usually EMB includes the force sensor for controlling the actuator and solenoid-lever structure for EPB function. The highly responsive and independent brake actuators lead to enhanced controllability which should result in not only better basic braking performance, but also improvements in various active braking functions such as integrated chassis control, driver assistance systems, or cooperative regenerative braking. Although the EMB system has the potential for numerous advantages and innovations in braking, it has yet to be successfully introduced in series production mainly due to safety and cost concerns.
Event
2014-09-25
This session will cover papers/presentations on aircraft electric actuation system (AEAS). Potential topics include all forms of electric actuation, including motors, controllers, regen power, reliability, and thermal management; how the electric actuation system impacts the power system of an aircraft; and system level benefits and impacts.
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