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991.
Gerardo Gabriel Acosta Miguel Angel Mayosky José Maria Catalfo 《Applied Intelligence》1994,4(1):53-66
This article proposes a scheme for the on-line adjustment of three mode controller settings based on experimental measurements of closed-loop performance. It uses a recently developed heuristic tuning procedure to identify estimated process parameters. This method may give rise to conflicting estimates. Fuzzy Set theory is applied to manage the situation in terms of a fuzzy conjunction to combine the various estimates. PID control was chosen because of its wide use in the industrial environment due to driving simplicity and robustness. The article shows design, development, and computer simulation aspects. 相似文献
992.
Dr. C. R. Nagarajah W. Thompson 《The International Journal of Advanced Manufacturing Technology》1994,9(5):333-342
There are two aspects to cell formation in flexible manufacturing systems, cell sizing or deciding on the optimum number of machines to be allocated to each cell, and then allocation of specific machines to each cell. Although the latter problem has been investigated extensively there is a paucity of published work on the former. This paper discusses the effects of cell sizing on operational flexibility.Operational flexibility is that aspect of flexibility that enables manufacturing systems to respond with speed and efficiency to changes in the manufacturing environment while maintaining an effective level of control. 相似文献
993.
陈代权 《小型微型计算机系统》1994,(6)
本文提出一种新的网络访问方式。它引入了同步时钟和令牌链,使得各点可共享一条通信数据线而访问控制电路却简单到仅用几个D触发器即可实现。它具有传统令牌方式所没有的一些优点。在通信量较少,速度要求不高的场合,其效果很好。文中讨论的一种应用方式。 相似文献
994.
This paper considers the trajectory tracking problem for uncertain robot manipulators and proposes two adaptive controllers as solutions to this problem. The first controller is derived under the assumption that the manipulator state is measurable, while the second strategy is developed for those applications in which only position measurements are available. The adaptive schemes are very general and computationally efficient since they do not require knowledge of either the mathematical model or the parameter values of the manipulator dynamics, and are implemented without calculation of the robot inverse dynamics or inverse kinematic transformation. It is shown that the control strategies ensure uniform boundedness of all signals in the presence of bounded disturbances, and that the ultimate size of the tracking errors can be made arbitrarily small. Experimental results are presented for a PUMA 560 manipulator and demonstrate that accurate and robust trajectory tracking can be achieved by using the proposed controllers. 相似文献
995.
本文自行研制了一台Fabry—Perot干涉仪及其用于探测超声信号的测试系统。利用该系统对非光学表面的铝板和铜板实现了nm级窄脉冲激光超声信号的非接触式检测,其信噪比足以满足进一步信号处理要求。 相似文献
996.
To acquire maximum information on the geometrical errors of industrially made surfaces at a minimum cost, a method for estimating conditional probabilities of a random signal (Bayesian prediction) is applied to three-dimensional metrology. First, a surface is interpolated between data acquired on a coordinate measuring machine (CMM). Then, for a given probability, limit surfaces are computed that bind a region of space containing the known data and the most probable interpolation of the missing data of the surface. These bounds can be treated as the surface; their points can be considered as if they were actual CMM data when fitting a tolerance zone or a datum feature to the data. For Bayesian prediction, the basic hypotheses on the signal are stationarity, ergodicity, and gaussian density. Deviations from these hypotheses and their consequences on the prediction are taken into account and corrections are proposed. 相似文献
997.
实时跟踪控制系统中的数字滤波技术 总被引:2,自引:0,他引:2
在高精度的实时跟踪控制系统中,由探测器等其他一些因素给系统带来的噪声将不容忽视,数字滤波将是滤除噪声的有效手段,,由于系统实时性和采样频率的要求,本文介绍几种时跟踪系统中常用的数字滤波方法,并对它们在实时跟踪系统中的作用进行了和比较。 相似文献
998.
本文针对某一钢铁厂的一套小方坯连铸机结晶器液面自动控制系统,对其故障原因进行了深入分析,指出导致系统控制性能达不到设计要求长期无法投入运行的主要原因,并提出了相应的解决方法。 相似文献
999.
J. R. Prez-Correa F. R. Sepúlveda M. A. Duarte 《International Journal of Adaptive Control and Signal Processing》1995,9(2):183-197
This paper presents experimental results obtained in temperature adaptive control of a heating vessel. A non-linear model of the process showed that the feed flow rate causes severe variations in time constant and process gain. An extended horizon self-tuning controller and two different model reference adaptive controllers were tested. The influence of design parameters on control performance for each algorithm was assessed. The control system was disturbed with load and setpoint changes. 相似文献
1000.
Existence results for the LQG-controller are investigated. An infimal Riccati equation based controller may potentially give closed loop eigenvalues on the unit circle. Assuming left and right invertibility it is shown that there exists an optimal controller if and only if the Riccati equation based controller stabilizes the closed loop system after removal of all its unobservable and uncontrollable modes. Furthermore this reduced controller is the optimal controller, and its transfer function is unique. This existence condition is a considerable simplification of the more general geometric condition recently derived by Trentelman and Stoorvogel. 相似文献