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691.
S. Kidane L. Alexander R. Rajamani P. Starr M. Donath 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(4):295-322
One way of addressing traffic congestion is by efficiently utilizing the existing highway infrastructure. Narrow tilting vehicles that need a reduced width lane can be part of the solution if they can be designed to be safe, stable, and easy to operate. In this paper, a control system that stabilizes the tilt mode of such a vehicle without affecting the handling of the vehicle is proposed. This control system is a combination of two different types of control schemes known as steering tilt control (STC) and direct tilt control (DTC) systems. First, different existing variations of both STC and DTC systems are considered and their shortcomings analysed. Modified control schemes are then suggested to overcome the deficiencies. Then a new method of integrating these two control schemes that guarantees smooth switchover between the controllers as a function of vehicle velocity is proposed. The performance of the proposed STC, DTC, and integrated systems is evaluated by carrying out simulations for different operating conditions and some experimental work. The design of a second-generation narrow tilting vehicle on which the developed control system has been implemented is presented. 相似文献
692.
V. Cossalter R. Lot M. Massaro 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(4):339-353
The chatter of motorcycles appears during braking and consists of a vibration of the rear and front unsprung masses at a frequency in the range of 17-22 Hz depending on the motorcycle. This vibration could be very strong and acceleration of the unsprung masses can reach 5-10 g. The chatter is an auto-excited vibration and this fact explains why it appears suddenly when the mechanism of auto-excitation is generated. This paper presents the chatter phenomenon both from an experimental and a numerical point of view. First, the chatter is defined on the basis of some experimental data from racing motorcycles and from the comments of some racing teams technicians. Then, chatter is analysed in different motion conditions and for different braking styles by means of linear and non-linear simulations of the motorcycle dynamics. A physical interpretation of the phenomenon is also proposed. 相似文献
693.
<正>虽然政府频频出台新能源利好政策,希望刺激消费者购买欲望,但研究显示,仅靠政策单方面刺激很难完成到2020年累计销售500万辆新能源车的目标,需要地方政府、汽车OEM和电网公司共同致力于推动新能源汽车的成功发展,解决充电等难题,从根本上消除消费者的顾虑。"中国消费者对新能源汽车(NEV)的兴趣及购买意愿仍不足以实现中国政府新能源汽车销量的目标。"中国是全球最大的汽车市场,而汽车业如火如荼的发展也同时造成了大城市的严重交通拥堵和空气污染。随着城镇化进程的不断推进(城镇人口有望从2014年 相似文献
694.
695.
该文采用有限元法建立了碎石化条件下混凝土路面二维平面应变模型,对标准轴载和超载条件下不同类型加铺层结构的力学响应进行计算,综合比较路面弯沉、层底拉应力、层底拉应变等各项指标,提出半刚性基层加薄层沥青罩面可作碎石化条件下的加铺层结构;通过优化比较,得出采用半刚性基层加沥青面层可满足设计要求,并对各种基层材料的抗干、温缩,抗水损害等性能进行了比较。 相似文献
696.
697.
Fault detection method for electric parking brake (EPB) systems with sensorless estimation using current ripples 总被引:1,自引:0,他引:1
C. W. Lee H. B. Chung Y. O. Lee C. C. Chung Y. S. Son P. Yoon 《International Journal of Automotive Technology》2010,11(3):387-394
A fault detection method with parity equations is proposed in this paper. Due to its low cost implementation, the velocity
of the motor is not measurable in electric parking brake (EPB) systems. Therefore, residuals are not reliable when estimating
the motor velocity with a low-resolution encoder. In this paper, we propose a fault detection method with sensorless estimation
using current ripples that estimates the position and velocity of the motor by detecting periodical oscillations of the armature
current caused by rotor slots. In addition, this method can estimate the position and velocity of the motor with less computational
effort than a state observer. Moreover, the method is less sensitive to motor parameters than model-based estimation methods.
The effectiveness of this method is validated with experimental data, and the simulation results show that various faults
have their own residual patterns. Therefore, we can detect the presence of faults by monitoring the residual signals. 相似文献
698.
H. J. Kim B. Han W. S. Hong W. H. Shin G. B. Cho Y. K. Lee Y. J. Kim 《International Journal of Automotive Technology》2010,11(4):447-453
A 3000 cc diesel engine attached to an engine dynamo was used to test three newly developed electrostatic Diesel Particulate
matter filtration Systems (DPS 1, 2, and 3) under four steady-state engine operating conditions: idle, 2000 rpm with no load,
and 2000 rpm under 25% and 50% loads. Of the two developed alternatives, DPS 1 and DPS 2, DPS 2 comprises an ionization section,
electrostatic field additional section and Flow-Through Filter (FTF), which achieved almost 90% removal of particulate matter
(PM) under the engine’s operating conditions, and the efficiency of the FTF was maintained between 20% and 50%. Comparing
the long-term performance of DPS 2 and DPS 3 (effectively a serial combination of two DPS 2s) with a commercially-available
Diesel Particulate Filter (DPF), the DPS 2 and DPS 3 achieved almost the same efficiency for removing PM as the DPF but had
significantly improved (75%∼90% lower) differential pressure drops. 相似文献
699.
The importance of vehicle safety cannot be exaggerated in today’s mobile societies. Many manufacturers, associates related
to vehicles and universities make an effort to improve vehicle safety by developing new technologies, applying high strength
steel to the body structure etc. However, the majority of these efforts are focused on decreasing injury. It is absolutely
important to minimize injury, but a more important aspect is coping with vehicle accidents. That is, As undeniably important
as it is to minimize potential injuries, it is critical that experts focus on developing ways to keep drivers out of situations
likely to lead to crashes in the first place. The purpose of this paper is to determine what the most critical factor is when
coping with an unfamiliar driving situation. The answer is to provide a wide-open field of vision, especially for the driver.
The driver’s field of vision is obstructed by the vehicle’s A-pillar. To solve this, the A-pillar obstruction angle, which
is the angle between the driver’s eyes and the A-pillar should be decreased. This paper purposes three-methods for decreasing
this angle structurally and applying a slim A-pillar which is as the best solution to decrease the A-pillar obstruction angle
and ensure the drivers field of vision at the same time 相似文献
700.