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基于轮速脉冲的自动泊车定位精度研究
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作者 张雷 《汽车实用技术》 2024年第5期36-40,共5页
基于车辆轮胎脉冲的自动泊车定位系统,针对其轮胎半径的变化导致的车辆定位精度误差变大问题,文章提出了一种简易的轮胎脉冲长度补偿方法。该方法首先基于车辆直线行驶时的车辆四轮轮胎脉冲数计算各自的行驶距离。其次,分别基于四轮脉... 基于车辆轮胎脉冲的自动泊车定位系统,针对其轮胎半径的变化导致的车辆定位精度误差变大问题,文章提出了一种简易的轮胎脉冲长度补偿方法。该方法首先基于车辆直线行驶时的车辆四轮轮胎脉冲数计算各自的行驶距离。其次,分别基于四轮脉冲计算四轮的行驶距离及四轮平均行驶距离,并基于计算的四轮平均行驶距离对车辆的四轮脉冲长度进行补偿。最后,基于补偿后的轮胎脉冲长度计算车辆的位姿变化。实车测试表明,补偿后的轮胎脉冲长度可以提高车辆的定位精度。 展开更多
关键词 自动泊车 脉冲 车辆定位 误差补偿
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C50-90/13-Ⅱ型汽轮机组转速探头失效故障诊断及处理 被引量:1
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作者 马斌 张鹏 +1 位作者 杨彩燕 沈红霞 《冶金动力》 2021年第2期39-41,共3页
针对C50-90/13-Ⅱ型汽轮机小轴头和测速脉冲轮径向跳动超标,造成转速探头碰磨的故障,进行检修过程跟踪及原因分析,提出了解决措施,确保了机组安全稳定生产。
关键词 转速探头失效 小轴头 转速脉冲轮 径向跳动超标
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丰田陆地巡洋舰4700故障1例
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作者 杨洪举 《汽车与驾驶维修》 2005年第8期38-38,共1页
一辆UZJ100L-GNPEKV丰田陆地巡洋舰4700越野车,行驶里程226798km,该车发动机怠速着车时,发动机发抖,行车加速不良。
关键词 丰田陆地巡洋舰4700越野车 发动机 汽车维修 变速器 脉冲轮
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Taper Angle Correction in Cutting of Complex Micro-mechanical Contours with Ultra-Short Pulse Laser 被引量:4
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作者 J. Auerswald A. Ruckli +3 位作者 T. Gschwilm P. Weber D. Diego-Vallejo H. Schliiter 《Journal of Mechanics Engineering and Automation》 2016年第7期334-338,共5页
The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS ... The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS micro machining sub system. In a first step, the influence of the process parameters on the kerftaper angle of metallic alloys was systematically investigated without beam inclination. A set of base parameters was derived for the subsequent investigations. In a second step, the kerftaper angle was controlled by static beam inclination. In a third step, the same optics was used in its dynamic precession mode to fabricate micro-mechanical components of complex contours with perpendicular 0~ taper angles. It was found that taper angle adjustments of up to 7.5~ are possible with the used setup for cutting applications. Taper angle control is possible both in the static beam inclination mode and in the dynamic precession mode. The static mode could be interesting for contours with sharp inner radii and for achieving faster cutting times similar to results with fixed optics, but would require excellent synchronization of beam inclination and axis motion. The dynamic precession mode would allow an easier integration of the optics into a laser machine but will result in longer cutting times and limitations with respect to achievable inner radii. 展开更多
关键词 Ultra-short pulse laser cutting kerf taper angle zero taper 5-axis micro machining.
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Impulsive dynamics and stabilization of a single wheel robot
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作者 Ou Yongsheng Wu Xinyu Xu Yangsheng 《Engineering Sciences》 EI 2011年第1期76-83,共8页
The impulsive motion of a dynamically stabilized robot—Gyrover, which is a single-wheel gyroscopically stabilized robot is studied. A method based on the D’Alembert-Lagrange principle is proposed to develop the impu... The impulsive motion of a dynamically stabilized robot—Gyrover, which is a single-wheel gyroscopically stabilized robot is studied. A method based on the D’Alembert-Lagrange principle is proposed to develop the impulsive dynamic model of the single wheel robot. This method that can be used to find ways to investigate a single wheel mobile robot rolling on a rough terrain is tested using the experimental platform Gyrover. The conditions of falling over without actuators are addressed. Simulations that validate the analysis are provided as well. 展开更多
关键词 impulsive dynamics single wheel robot dynamically stabilized system
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An improved phase measurement method of integrated pulse profile for pulsar 被引量:10
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作者 ZHANG Hua XU LuPing 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第9期2263-2270,共8页
Integrated profile is one of the basic characteristic of X-ray pulsar. Gaussian function fit is used to model the components of X-ray pulsar profile, and it is combined with Poisson distribution model of X-ray pulsar ... Integrated profile is one of the basic characteristic of X-ray pulsar. Gaussian function fit is used to model the components of X-ray pulsar profile, and it is combined with Poisson distribution model of X-ray pulsar to analyze Cramer-Rao low bound (CRLB) of phase, phase rate estimation and relation between CRLB and profile components. Then, a time domain method using minimum entropy is proposed for profile phase and phase rate estimation, and its effectiveness is explained using simulation examples. 展开更多
关键词 PULSARS phase measurement Cramer-Rao minimum entropy
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Effects of pulse flow and leading edge sweep on mixed flow turbines for engine exhaust heat recovery 被引量:2
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作者 ZHANG YangJun CHEN Li +1 位作者 ZHUGE WeiLin ZHANG ShuYong 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第2期295-301,共7页
Recovery of heat energy from internal combustion engine exhaust will achieve significant road transportation CO2 reduction. Turbocharging and turbogenerating are most commonly used technologies to recover engine exhau... Recovery of heat energy from internal combustion engine exhaust will achieve significant road transportation CO2 reduction. Turbocharging and turbogenerating are most commonly used technologies to recover engine exhaust heat energy.Engine exhaust pulse flow can significantly affect the turbine performance of turbocharging and turbogenerating systems,and it is necessary to consider the pulse flow effects in turbine design and performance analysis.An investigation was carried out by numerical simulation on the mixed flow turbine pulse flow performance and flow fields.Results showed that the variations of the turbine efficiency and flowfiled under pulsating flow conditions demonstrate significant unsteady effects.The effect of blade leading edge sweep on turbine pulse flow performance was studied.It is shown that increasing of the leading edge sweep angle can improve the turbine average instantaneous efficiency by about 2 percent under pulsating flow conditions. 展开更多
关键词 waste heat recovery mixed flow turbine pusle flow
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Feasibility of Pulse Combustion in Micro Gas Turbines 被引量:2
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作者 Juha Honkatukia Esa Saari +2 位作者 Timo Knuuttila Jaakko Larjola Jari Backman 《Journal of Thermal Science》 SCIE EI CAS CSCD 2012年第5期466-473,共8页
In gas turbines, a fast decrease of efficiency appears when the output decreases; the efficiency of a large gas tur-bine (20...30 MW) is in the order of 40 %, the efficiency of a 30 kW gas turbine with a recuperator... In gas turbines, a fast decrease of efficiency appears when the output decreases; the efficiency of a large gas tur-bine (20...30 MW) is in the order of 40 %, the efficiency of a 30 kW gas turbine with a recuperator is in the order of 25 %, but the efficiency of a very small gas turbine (2...6 kW) in the order of 4...6 % (or 8... 12 % with an op- timal recuperator). This is mainly a result of the efficiency decrease in kinetic compressors, due to the Reynolds number effect. Losses in decelerating flow in a flow passage are sensitive to the Reynolds number effects. In con- trary to the compression, the efficiency of expansion in turbines is not so sensitive to the Reynolds number; very small turbines are made with rather good efficiency because the flow acceleration stabilizes the boundary layer. This study presents a system where the kinetic compressor of a gas turbine is replaced with a pulse combustor. The combustor is filled with a combustible gas mixture, ignited, and the generated high pressure gas is expanded in the turbine. The process is repeated frequently, thus producing a pulsating flow to the turbine; or almost a uni- form flow, if several parallel combustors are used and triggered a/ternately in a proper way. Almost all the com- pression work is made by the temperature increase from the combustion. This gas turbine type is investigated theoretically and its combustor also experimentally with the conclusion that in a 2 kW power size, the pulse flow gas turbine is not as attractive as expected due to the big size and weight of parallel combustors and due to the ef- ficiency being in the order of 8 % to 10 %. However, in special applications having a very low power demand, below 1000 W, this solution has better properties when compared to the conventional gas turbine and it could be worth of a more detailed investigation. 展开更多
关键词 Gas turbine pulse combustion micro size low Reynolds number
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