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经典反馈控制将对象动态响应的控制和噪声的消除放在同一个过程中进行,这种方法往往会产生为了满足一个指标而牺牲另外一个指标的矛盾.本文介绍了一种新的控制方法--自适应逆控制,阐述了自适应逆控制的特点,讨论了自适应逆控制系统的三个基本单元--对象建模、逆控制器建模和扰动消除器.自适应逆控制将对象动态响应的控制和噪声的消除分开来考虑,解决了上述经典反馈控制的矛盾.在仿真软件Matlab上进行船舶自动舵仿真时,分别采用了自适应逆控制方案的ELS(增广最小二乘)算法和经典反馈控制的PID(比例积分微分)算法.仿真结果表明了自适应逆控制的优点. 相似文献
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基于查德惠克被动式减摇水舱理论,分别建立了单侧气阀和两侧气阀控制的可控被动式减摇水舱系统数学模型.推导了最佳相位关系和气阀控制规律的理论依据,对不规则波作用下的可控被动式减摇水舱系统进行了仿真研究.仿真结果表明,水舱内水的流动与船舶横摇运动基本符合最佳相位关系,气阀控制规律是可行的.通过对单侧或者两侧气阀进行控制,都能够使水舱内水流的振荡周期及时地适应变化的横摇周期.两侧气阀控制的减摇效果要优于单侧气阀控制. 相似文献
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When an aircraft moves under a low carrier-to-noise ratio (CNR) or at a high speed, increasing the sensitivity of global navigation
satellite system (GNSS) receiver is a goal quite hard to achieve. A novel acquisition scheme assisted with micro-electro-mechanical-sensor
(MEMS) inertial navigation system (INS) is presented to estimate the Doppler caused by user dynamics relative to each satellite
ahead of time. Based on tightly coupled GNSS/INS estimation algorithm, MEMS INS Doppler error that can be achieved is first
described. Then, by analyzing the mean acquisition time and signal detection probability, the MEMS INS-assisted acquisition
capabilities in cold, warm and hot starts are quantitatively determined and compared with the standard GNSS acquisition capability.
The simulations and comparisons have shown that: the acquisition time in cold start can be shortened by at least 23 s, the
time in warm start can be shortened to 1 s and the acquisition capability is improved 95%, and the reacquisition time in hot
start can be shortened by around 0.090 s and the capability can be enhanced 40%. The results demonstrate the validity of the
novel method. 相似文献