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151.
阎菲 《湖北汽车工业学院学报》2000,14(4):50-57
模糊控制是对液压伺服系统控制的有效手段。本文针对一般模糊控制算法存在的问题 ,采用控制规则智能调节因子和 Fuzzy/PI分段控制等一系列措施 ,克服了传统模糊控制器的缺陷。进行了模糊控制的仿真研究 ,仿真结果表明上述控制系统优于传统的线性控制。 相似文献
152.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1642-1657
The paper describes a simulation study that provides a comprehensive comparison between full-active and semi-active suspensions for improving the vertical ride quality of railway vehicles. It includes an assessment of the ride quality benefits that can theoretically be achieved with idealised devices, and also examines the impact of real devices based upon hydraulic actuation technology. 相似文献
153.
一种新型随动系统研制成功并配炮装舰,可大大提高装备水平。但是,由于与以往设备不同,这无论给使用该设备的战士,还是后勤保障都带来新的要求。在使用阶段保证平时战备完好性和战斗使用要求是综合保障的重要工作内容。其中,最主要的是使用人员和维护保养人员的技术水平、保障设备以及备件(品)的合理配置。做好这些主要工作,才有可能使设备发挥最大效能。 相似文献
154.
郑丽萍 《武汉船舶职业技术学院学报》2006,5(1):45-47
通过对数控系统补偿功能有关数据的计算和设置,实现了对机床伺服轴定位误差进行补偿,使该项误差限制在机床允许误差范围内,提高了机床的加工精度。 相似文献
155.
156.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):256-273
This work deals with how to utilise active suspension on individual vehicle wheels in order to improve the vehicle performance during straight-line braking. Through numerical optimisation, solutions have been found as regards how active suspension should be controlled and coordinated with friction brakes to shorten the braking distance. The results show that, for the studied vehicle, the braking distance can be shortened by more than 1?m when braking from 100?km/h. The applicability of these results is studied by investigating the approach for different vehicle speeds and actuator stroke limitations. It is shown that substantial improvements in the braking distance can also be found for lower velocities, and that the actuator strokes are an important parameter. To investigate the potential of implementing these findings in a real vehicle, a validated detailed vehicle model equipped with active struts is analysed. Simplified control laws, appropriate for on-board implementation and based on knowledge of the optimised solution, are proposed and evaluated. The results show that substantial improvements of the braking ability, and thus safety, can be made using this simplified approach. Particle model simulations have been made to explain the underlying physical mechanisms and limitations of the approach. These results provide valuable guidance on how active suspension can be used to achieve significant improvements in vehicle performance with reasonable complexity and energy consumption. 相似文献
157.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1553-1573
There is a need to further improve driver comfort in commercial vehicles. The variable geometry active suspension offers an interesting option to achieve this in an energy efficient way. However, the optimal control strategy and the overal performance potential remains unclear. The aim of this paper is to quantify the level of performance improvement that can theoretically be obtained by replacing a conventional air sprung cabin suspension design with a variable geometry active suspension. Furthermore, the difference between the use of a linear quadratic (LQ) optimal controller and a classic skyhook controller is investigated. Hereto, an elementary variable geometry actuator model and experimentally validated four degrees of freedom quarter truck model are adopted. The results show that the classic skyhook controller gives a relatively poor performance while a comfort increase of 17–28% can be obtained with the LQ optimal controller, depending on the chosen energy weighting. Furthermore, an additional 75% comfort increase and 77% energy cost reduction can be obtained, with respect to the fixed gain energy optimal controller, using condition-dependent control gains. So, it is concluded that the performance potential using condition-dependent controllers is huge, and that the use of the classic skyhook control strategy should, in general, be avoided when designing active secondary suspensions for commercial vehicles. 相似文献
158.
电液位置伺服系统是最常见的伺服系统之一,已广泛应用于各个行业。介绍了电液位置伺服系统的工作原理,在通过用ITAE准则优化方法对系统进行优化,并采用MATLAB仿真工具进行仿真后,再以具体系统为例,详细说明了仿真和优化的全过程。经ITAE准则优化方法优化后,通过仿真,可以发现系统的性能得到了较大改善。 相似文献
159.
160.
Decang Li Jianjun Meng Huan Bai Ruxun Xu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(7):1028-1050
This paper focuses on the safety of high-speed trains under strong crosswind conditions. A new active control strategy is proposed based on the adaptive predictive control theory. The new control strategy aims at adjusting the attitudes of a train by controlling the new-type intelligent giant magnetostrictive actuator (GMA). It combined adaptive control with dynamic matrix control; parameters of predictive controller was real-time adjusted by online distinguishing to enhance the robustness of the control algorithm. On this basis, a correction control algorithm is also designed to regulate the parameters of predictive controller based on the step response of a controlled objective. Finally, the simulation results show that the proposed control strategy can adjust the running attitudes of high-speed trains under strong crosswind conditions; they also indicate that the new active control strategy is effective and applicable in improving the safety performance of a train based on a host–target computer technology provided by Matlab/Simulink. 相似文献