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81.
介绍宝马发动机电控系统诊断信息、车间诊断设备、电控发动机的重点组成部件。  相似文献   
82.
Two typical criteria for good vehicle suspension performance are their ability to provide good road handling and increased passenger comfort. The main disturbance affecting these two criteria is terrain irregularities. Active suspension control systems reduce these undesirable effects by isolating car body motion from vibrations at the wheels. This paper describes fuzzy and adaptive fuzzy control (AFC) schemes for the automobile active suspension system (ASS). The design objective is to provide smooth vertical motion so as to achieve the road holding and riding comfort over a wide range of road profiles. The efficacy of the proposed control schemes is demonstrated via simulations. With respect to the optimal linear quadratic regulator (LQR), it is shown that superior results have been achieved by the AFC.  相似文献   
83.
A grey prediction fuzzy controller (GPFC) was proposed to control an active suspension system and evaluate its control performance. The GPFC employed the grey prediction algorithm to predict the position output error of the sprung mass and the error change as input variables of the traditional fuzzy controller (TFC) in controlling the suspension system to suppress the vibration and the acceleration amplitudes of the sprung mass for improving the ride comfort of the TFC used; however, the TFC or GPFC was employed to control the suspension system, resulting in a large tire deflection so that the road-holding ability in the vehicle becomes worse than with the original passive control strategy. To overcome the problem, this work developed an enhancing grey prediction fuzzy controller (EGPFC) that not only had the original GPFC property but also introduced the tire dynamic effect into the controller design, also using the grey prediction algorithm to predict the next tire deflection error and the error change as input variables of another TFC, to control the suspension system for enhancing the road-holding capability of the vehicle. The EGPFC has better control performances in suppressing the vibration and the acceleration amplitudes of the sprung mass to improve the ride quality and in reducing the tire deflection to enhance the road-holding ability of the vehicle, than both TFC and GPFC, as confirmed by experimental results.  相似文献   
84.
This paper provides an overview of a theoretical study of an active seat suspension. The principal objective of this study is to improve ride passenger comfort by reducing transmitted seat acceleration. The seat is represented by a non-linear two degree of freedom model. The system is linearized for small perturbations around the equilibrium. To control the dynamic of the seat suspension, an original feedback control command with a reversible electromechanical actuator is achieved. The synthesis of the regulator is realized on the linearized model of the seat suspension and the root locus method is employed. Stability and robustness characteristics have been studied. Numerical simulations in time and frequency domain show the interests of the regulator and its capability to isolate seat passenger.  相似文献   
85.
The fault-tolerant control (FTC) of heavy-haul trains is discussed on the basis of the speed regulation proposed in previous works. The fault modes of trains are assumed and the corresponding fault detection and isolation (FDI) are studied. The FDI of sensor faults is based on a geometric approach for residual generators. The FDI of a braking system is based on the observation of the steady-state speed. From the difference of the steady-state speeds between the fault system and the faultless system, one can get fault information. Simulation tests were conducted on the suitability of the FDIs and the redesigned speed regulators. It is shown that the proposed FTC does not explicitly worsen the performance of the speed regulator in the case of a faultless system, while it obviously improves the performance of the speed regulator in the case of a faulty system.  相似文献   
86.
通过加装控制盒的方式,实现单探头测深仪与自动控制探头之间的流畅切换,将传统单探头测深仪改造成具有多探头功能的高效水下测量仪器系统,主要用于航道和码头基床等的水下扫测。利用该系统进行的码头基床扫测已经取得成功,可为同类测量设备的改造提供全新的思路。  相似文献   
87.
The development of a parametric hull form design system utilizing combined knowledge-based and objectoriented methodologies, approaches, and techniques is the major purpose of this research. One objective was the development of a powerful, intuitive, and parameter-based hull definition system with a related hull definition advisory system that would provide useful and necessary advice to the user. Object and knowledge modeling activities were conducted during the analysis and design stage to facilitate the implementation of a hull design program and advisory system. The hull design system includes the generation of a geometric model from a process of aggregating simple user-selected shapes representing different boundaries. Design involves the capability to vary simple parameters such as entrance angles, length-breadth ratios, and radii to define local and general surface geometries. Hydrostatic calculations are included for analysis; results are referred to an advisory system for evaluation and the determination of the acceptability of parameters and analysis results. The advisory system includes a knowledge bases consisting of hull form databases, results of the statistical analysis of data, design parameter constraints, and expert knowledge acquired from designers, reference materials, and technical reports. Use of the design tool with the advisory system results in the rapid generation of hull forms and associated design evaluations. Flexibility in decision making results from the separation of the design system from the advisory system. The independence of the two systems allows for a wide range of user experience with experts using the design tool with minimal reference to the advisory system. On the other hand, the expertise and knowledge stored in the advisory system is fully available to inexperienced designers and users.  相似文献   
88.
集装箱电子标签系统的研究和应用   总被引:3,自引:1,他引:3  
为了提高集装箱运输的管理水平,研究开发了具有世界领先技术水平的集装箱电子标签系统,并率 先在内贸集装箱运输中应用示范,取得了阶段性成果。本文着重介绍内贸集装箱电子标签自动识别应用系统的体 系结构、主要技术内容、特点和示范线整体方案。  相似文献   
89.
介绍了一种智能决策系统的结构设计,此设计以黑板体系为构架,通过内置的黑板结构、知识源结构及椎理控制策略为CGF提供一个简易、友好的智能决策系统。在决策推理决策中,由于不精确推理算法的使用,使得此智能决策系统决策快速而准确,满足了CGF智能决策的需求。  相似文献   
90.
舰船设计方案评估指标体系研究   总被引:5,自引:3,他引:5  
针对舰船研制特点,运用系统工程原理,通过对任务目标的分解与技术指标的分析,考虑全系统、全寿命、满足用户需求,将传统工程设计与现代专业工程进行系统综合,构建了可用于舰船研制方案的评估、权衡、优化的舰船研制指标体系.此外对其应用条件和应用形式进行了初步探讨.  相似文献   
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