Simulation of adaptive optics for the Vacuum Tower Telescope     

Anita Enmark  Thomas Berkefeld  Oskar von der Lühe  Torben Andersen 《Experimental Astronomy》2006,21(2):87-99

A simulation model of the adaptive optics of the German Vacuum Tower Telescope (VTT), Observatorio del Teide, Tenerife, is presented. The model uses modules from the integrated model of the Euro50 extremely large telescope, and includes submodels of a Shack-Hartmann wavefront sensor, a de-formable mirror, a tip-tilt mirror, high-voltage amplifier low-pass filters, a reconstructor and a controller. We investigate the impact on the closed loop bandwidth of changes in controller configuration and certain system parameters, such as low pass filter bandwidth and camera integration and readout time. Control strategies were tested on simple models before implementation on the full VTT model. Using the models, different control strategies are compared.  相似文献   

激变变星0623＋71的光谱研究     

袁钧涛  李宗云 《天文学报》1996,37(3):235-242

本文提出了激变变星０６２３十７１的４个时间分辨光谱，覆盖轨道周期的７３％．其中的３个谱清楚地显示了各种光谱特征随轨道运动的变化，在流量、能谱以及谱线轮廓方面的这种变化正是对一个倾角不太大的激变变星所期望的．然而另一个曝光对分钟的谱，流量和视向速度与预期的相比都太大，很难加以解释，可能它是一次象ＡＥＡｑｒ中观测到的跃发事件．  相似文献   

基于专家系统决策的多模式控制及其应用     

宣森 《广东海洋大学学报》1993,(1)

将专家系统技术与常规控制、模糊控制、超前控制、仿人智能操作控制以及计算机控制技术相结合,设计了一种新的基于专家系统决策的多模式控制(MCDBES)。经试验和实际运行结果表明,MCDBES系统对未知数学模型的被控对象,具有良好的控制性能。本文提出的MCDBES已成功地应用于燃油陶瓷窑炉计算机控制系统。  相似文献   

激变食变星PG0027+260的CCD光变曲线     

李泳  蒋兆基  陈建生  魏名智 《中国天文和天体物理学报》1990,(2)

我们于1989年11月30日晚对PG0027+260进行了时间分辨率为108秒的高速CCD测光,得到了一条完整的光变曲线,从而确认其为激变食变星系统,轨道周期0.146~d  相似文献   

增氧机自动控制电路     

钟文颖  张钟世 《中国海洋大学学报(自然科学版)》1995,(Z1)

介绍作者自行设计、研制的控制增氧机运行时间的自动控制电路及其原理．该电路采用ＣＭＯＳ集成芯片，结构简单、工作可靠，价格低，业经试验证实：各项性能指标均符合要求．  相似文献   

富钴结壳分布的分形特征   总被引：8，自引：0，他引：8  

何高文 《海洋地质与第四纪地质》2001,21(1):89-92

利用我国在西太平洋国际海底两个海山获得的富钴结壳资料进行分形研究后发现，富钴结壳的分布具有变维分形分布的特点，结壳丰度呈二阶累计和分形分布，结壳厚度呈多阶不定累计和分形分布，通过计算得到了它们各自的分维数，进而对两个海山的结壳资源进行了初步评价。  相似文献   

Fractal Dimension and Fractals in Ocean Engineering   总被引：4，自引：0，他引：4  

Fu Yuhua Senior Engineer  China Offshore Oil Engineering Corporation  P. O. Box  Beijing 《中国海洋工程》1994,(3)

- This paper discusses the application of fractal dimension and fractals in ocean engineering. To handle some ocean environment problems, the existing fractal method, in which the fractal dimension is a constant, can be used. For some complicated problems in ocean engineering, this paper presents the concept of the variable dimension fractals (D = f(r)), i. e., the fractal dimension D is the function of characteristic scale r instead of a constant. By using variable dimension fractals, several deformation and stress states of offshore structures are described.  相似文献   

The nonlinear hydrodynamic model for simulating a ship steering in waves with autopilot system     

Ming-Chung Fang  Jhih-Hong Luo 《Ocean Engineering》2005,32(11-12):1486-1502

In the paper, a hydrodynamic numerical model including wave effect is developed to simulate ship autopilot systems by using the time domain analysis. The PD controller and the sliding mode controller are adopted as the autopilot systems. The differences of simulation results between two controllers are analyzed by cost function composed of heading angle error and rudder deflection, either in calm water or in waves. The results in calm water show that both controllers are tracking well for the desired route with the similar cost function value by tuning the key design parameters. However, the course tracking ability of the controller using sliding mode in waves is generally better even the cost function value is similar.  相似文献   

Path following control system for a tanker ship model     

Lúcia Moreira  Thor I. Fossen  C. Guedes Soares   《Ocean Engineering》2007,34(14-15):2074-2085

A two-dimensional path following control system for autonomous marine surface vessels is presented. The guidance system is obtained through a way-point guidance scheme based on line-of-sight projection algorithm and the speed controller is achieved through state feedback linearization. A new approach concerning the calculation of a dynamic line-of-sight vector norm is presented which main idea is to improve the speed of the convergence of the vehicle to the desired path. The results obtained are compared with the traditional line-of-sight scheme. It is intended that the complete system will be tested and implemented in a model of the “Esso Osaka” tanker. The results of simulations are presented here showing the effectiveness of the system aiming in to be robust enough to perform tests either in tanks or lakes.  相似文献   

A hierarchical real-time control architecture for a semi-autonomous underwater vehicle   总被引：1，自引：0，他引：1  

Ji-Hong Li  Bong-Huan Jun  Pan-Mook Lee  Seok-Won Hong 《Ocean Engineering》2005,32(13):282-1641

This paper describes a real-time control architecture for Dual Use Semi-Autonomous Underwater Vehicle (DUSAUV), which has been developed at Korea Research Institute of Ships and Ocean Engineering (KRISO) for being a test-bed of development of underwater navigation and manipulator technologies. DUSAUV has three built-in computers, seven thrusters for six DOF motion control, one 4-function electric manipulator, one ballasting motor, built-in power source, and various sensors. A supervisor control system with GUI and a multi-purpose joystick is mounted on the surface vessel and communicates with vehicle through a fiber optic link. Furthermore, QNX, one of real-time operating system, is ported on the built-in control and navigation computers for real-time control purpose, while Microsoft OS product is ported in the supervisor computer for GUI programming convenience. A hierarchical control architecture, which consists of application layer, real-time layer and physical layer, has been developed for efficient control system of above complex underwater robotic system. The experimental results with implementation of the layered control architecture for various motion control of DUSAUV in an ocean engineering basin of KRISO is also presented.  相似文献