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626.
基于台车试验方法的某微型轿车乘员约束系统改进设计 总被引:2,自引:1,他引:1
在试验基础上对某微型轿车无气囊条件下的约束系统进行优化,分析了座椅、转向盘和安全带的动态特性,提出了减小乘员伤害值的改进方案.通过台车试验证明,该微型轿车正面碰撞乘员保护达到中国法规要求,改进方案正确和有效;对于刚性很强的尺寸紧凑型微型轿车,弱化碰撞时头部接触位置的转向盘轮缘,并使用限力式安全带,可以有效降低正面碰撞头部加速度. 相似文献
627.
X. Li X. P. Zhao J. Chen J. L. Men 《International Journal of Automotive Technology》2009,10(4):497-503
The electric power steering (EPS) system is designed to reduce the effort exerted by driver on the steering wheel. One of
the most common and critical failures of EPS is the soft-disability of the torque sensor or the loss of its signal, which
leads to the instant shutdown of the EPS system while turning and causes serious traffic accidents. In this paper, a novel
controller based on the self-alignment torque (SAT) estimation was designed to remedy the soft-disability of EPS system. After
the SAT estimation method was verified by the empirical Magic Formula (MF) tire model, the remedy control strategy based on
the SAT estimation was developed and evaluated by simulations under step and sinusoidal inputs. To further evaluate the performance
of the controller on a real vehicle, experiments on a real EPS system were implemented under step and sinusoidal inputs. The
results of simulation and experiment using the controller based on estimated SAT showed this controller to be feasible and
capable of eliminating the abrupt reaction torque increment caused by shutdown of EPS and of remedying the soft-disability
of EPS system under common input signals. 相似文献
628.
J. H. Song J. X. Wang H. B. Tang X. J. Mao B. Zhuo 《International Journal of Automotive Technology》2009,10(4):523-528
A controller for a diesel hybrid electric vehicle based on a V-cycle development approach is investigated in this paper. The
hardware and infra program of the Hybrid Control Unit (HCU) are discussed in detail. The hardware system is designed based
on circuit simulation; while the infra system is written with assemble language. Time sharing mode, buffer sharing mode and
multi-task schedule method are used to ensure real-time communication in the infra program design. Based on multi-thread technology,
hardware in loop test system is also designed. The hardware in loop and bench tests show that the controller could meet the
requirements of the hybrid electric vehicle (HEV) and communicate in real-time. Circuit simulation, HCU, infra program and
hardware in loop test form the effective V-cycle development platform to design a hardware system for a diesel HEV controller. 相似文献
629.
Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis 总被引:3,自引:0,他引:3
Panel acoustic contribution analysis (PACA) is a practical engineering tool for the reduction of interior structure-borne
noise in passenger cars. In this study, the current PACA method has been improved for sound field refinement of the entire
interior. Two new parameters, the “acoustic contribution sum” and the “total sound field contribution”, are introduced to
analyze the interior sound field characterized with multiple field points and sound pressure peaks, and to evaluate the integrated
acoustic contributions of auto body panels. In addition, a systematic methodology for automotive interior sound field refinement
is also proposed on the basis of the modified PACA method. An example of a passenger car model demonstrates the application
of the sound-field-refinement methodology and shows the advantage of using damping layers at optimum locations on the auto
body. The example also shows that the modified PACA method has practical significance for refining the interior sound field
and decreasing added mass in accord with the trend towards lightweight auto bodies. 相似文献
630.
Physical-chemical properties of ethanol-diesel blend fuel and its effect on the performance and emissions of a turbocharged diesel engine 总被引:1,自引:0,他引:1
Z. -Q. Chen X. -X. Ma S. -T. Yu Y. -N. Guo J. -S. Liu 《International Journal of Automotive Technology》2009,10(3):297-303
This paper deals with the main physical-chemical properties of ethanol-diesel blend and the effects of ethanoldiesel blends
(up to 15% volume) on engine performance (full load torque vs. engine speed, BSEC vs. torque at 1400 r/min and 2300 r/min,
and effect of start of injection angle) and emissions in ECE R49 tests (steady 13 points) using a 6.6 L inline 6-cylinder
turbocharged direct injection diesel engine. The results show that an increase in ethanol fraction results in decreased viscosity
of the blend fuel and very high distillation characteristics in the low temperature range. Solvents can improve the solubility
of ethanol-diesel blends. The engine power was degraded proportional to the ethanol content (10% and 15%) due to the LHV (low
heating value) of the blends. The higher latent heat of vaporization and lower CN (cetane number) of ethanol, which results
from the steady state emissions of CO, HC, and SOF (soluble organic fraction), were much higher in the ECE R49 tests at low
loads. Soot (solid mass) emissions were improved. The particulate matter emissions were significantly increased with higher
blend volumes, and NOx emissions slightly increased with higher ethanol volumes. By increasing the injection angle properly,
the performance parameters of the diesel engine were improved, but NOx emissions were deteriorated slightly. 相似文献