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H. -Z. Li L. Li J. Song L. -Y. Yu 《International Journal of Automotive Technology》2011,12(5):679-686
A new comprehensive driver model is presented for critical maneuvering conditions with more accurate dynamic control performance.
In order to achieve a safe maneuvering mode, a new path planning scheme to maintain stability of the vehicle was designed.
A new steering strategy, considering the errors of vehicle position and yaw angle between the real track and the planned path,
was established to obtain the steering angle. Therefore, the vehicle can be adjusted to accurately follow the desired path
with the driver model, and the stability of the vehicle and the smoothness of the steering angle input were comprehensively
considered. Simulation results were used to validate the control performance in comparison with the optimal preview driver
model proposed by Macadam. 相似文献
897.
X. D. Wu S. G. Zuo L. Lei X. W. Yang Y. Li 《International Journal of Automotive Technology》2011,12(5):671-677
The purpose of this study was to effectively identify parameters for a LuGre friction model based on experimental measures.
In earlier work related to this study (Yang et al., 2009), which was based on the characters of polygonal wear (Sueoka and Ryu, 1997), we showed a frictional vibration model
for a mass on a moving belt. This model reflected lateral vibrations caused by velocity and toe-in angle. An important aspect
of the present study is the improved friction model. A previous friction model, which divided the process into four parts,
expressed the sable excited vibration well but failed to reflect the hysteresis loop change when vehicles accelerated or decelerated
continuously. A LuGre friction model can solve this problem, but several model parameters must be obtained experimentally.
We measured contact width and length of tires as vertical pressure changed; this provided a theoretical basis for apparent
stiffness of a unit of tire tread. Based on tire data from Bakker E’s article in a SAE paper from 1987, we identified the
Stribeck exponent and Stribeck velocity in LuGre. Then, the results were implemented in a vibration system that verified the
rationality of the data. 相似文献
898.
Regional passenger rail services are prevalent in France, as opposed to the more marginal role they play elsewhere in the world. It is indeed at the regional level that reforms have been successfully implemented, probably because the process was gradual and cautious. Initially in 1997, seven regions began experimenting with a decentralized system of regional passenger transportation services. By 2002, all metropolitan regions, with the exception of Corsica and Ile-de-France, were involved. Today we have reached a point where this process can be retrospectively and prospectively assessed. This article is first a retrospective assessment of the role of actors and the emerging dynamic between regional passenger rail transport supply and demand. Then, a prospective evaluation is offered since regionalization is best understood as an ongoing learning process that can be discontinuous or continuous. 相似文献
899.
周贤全 《变流技术与电力牵引》2005,(4):37-41
介绍EH200型直流供电电力机车的开发.为证实机车性能满足基本要求,至2001年6月完成了样机试验,并从2001年7月至2002年3月牵引列车进行了运营.通过这些试验和运营,证实该种机车能满足规定的性能,包括与地面设施的匹配. 相似文献
900.
赵歆光 《铁道标准设计通讯》2005,(1):56-56,59
强夯法处理地基具有施工简单、加固效果好、使用经济等优点 ,对于大能量强夯深层加固 ,先用中等能量级强夯形成较厚的浅层密实层 ,然后再施加大能量夯击的施工顺序才是提高施工效率和改进深层加固效果的有效途径 ,并举工程实例为证 相似文献