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小型固态航姿系统的研制

数据采集与处理 2003年第1期18卷 105-108页

作者：杨新勇黄圣国南京航空航天大学自动化学院南京210016 南京航空航天大学民航学院南京210016

通过分析罗差形成的原因 ,提出一种有效的罗差修正方法及基于最小二乘法的确定罗差系数的方法。完成了以 AT89C5.2为主控制器的小型固态航姿系统软硬件设计。采用主控制器与手持控制器协同工作的设计思想。使系统在工作现场的补偿过程... 详细信息

通过分析罗差形成的原因 ,提出一种有效的罗差修正方法及基于最小二乘法的确定罗差系数的方法。完成了以 AT89C5.2为主控制器的小型固态航姿系统软硬件设计。采用主控制器与手持控制器协同工作的设计思想。使系统在工作现场的补偿过程变得简单快速。实验结果表明 ,该系统修正效果明显 ,工作稳定可靠。

关键词：无人机磁阻传感器最小二乘法罗差修正

Observer-based Robust Fault Diagnosis for a Class of Uncertain Nonlinear Systems

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Observer-based Robust Fault Diagnosis for a Class of Uncerta...

2009中国控制与决策会议

作者： Lingya Meng~(1,2),Bin Jiang~1,Yufei Xu~1 1.college of automation engineering,nanjing university of{5. and astronautics,nanjing 210016,China 2.college of Information and Control engineering,China university of Petroleum,Dongying 25.061,China

＜正＞Robust fault diagnosis is investigated for a class of uncertain nonlinear flight control systems based on the adaptive observer.A new general fault updating law is presented to relax the assumption conditions of the adaptive *** addition,a simplified fault updating law is further presented for the case of constant *** asymptotical stability of the adaptive observer and the uniform ultimate boundedness of the fault estimation error vector are proved by Lyapunov *** effectiveness of the proposed scheme is demonstrated through the numerical simulation of a flight control system.

关键词： Fault Diagnosis Robust Nonlinear Adaptive Observer Flight Control

Experimental Study on the Milling of a Ti Beta 21S

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厦门大学学报（自然科学版） 2002年第S1期41卷 76-页

作者： XU Jiu-hua, GENG Guo-sheng (college of Mechanical and Electrical engineering, nanjing university o f aeronautics and{5., nanjing 210016, China)

Ti Beta 21S (Ti-15.o-2.7Nb-3Al-0.2Si) was devel op ed by TIMET in 1989. It is a metastable beta titanium alloy that offers subs tantial weight reductions over other engineering materials. Compared with common beta Ti alloys, it offers the high specific strength, good cold formability, im proved oxidation resistance, elevated temperature strength, creep resistance, an d thermal stability. Besides the common characters of titanium alloy, such as po or heat diffusivity, low elastic modulus, Ti Beta 21S has very high specific str ength and good plasticity. These make Ti Beta 21S a difficult-to-cut material. In this paper, the tool wear and cutting force in milling process were studied by experiment. The tool wear experiments were carried out in order to determine the opticmum cutting parameters and tool material, and the purpose of cutting fo rce measurement is to explain the cuting phenomenon and tool wear results in fur ther degree. The machinablity assessment of Ti Beta 21S with different cutting t ools was given out. As a difficult-to-cut material, Ti Beta 21S should be mill ed with sharp-edged tool at lower cutting parameters to avoid severe wear of th e tool. Coolant should be used to conduct cutting heat. Proper tool material sho uld be selected, for example, the cutting force by YS25.tool is 20 percent lower than that by YG8 at the milling speed of 80 m/min. The roughness of flank and r ake surface is another important factor that affects tool wear and cutting f orce, and Ra should be below 0.2 μm while milling Ti Beta 21S. These results wi ll be useful in the actual production process, and have thrown new light on the cutting of difficult-to-cut material.

关键词： titanium alloy milling tool wear cutting force

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二维条形码编码与译码的计算机实现

数据采集与处理 2003年第3期18卷 356-360页

作者：戴扬于盛林南京航空航天大学自动化学院南京210016

介绍了 PDF41 7二维条形码的特点和编码规则 ,详细阐述了用计算机实现其编码的原理和方法 ,并采用具体实例介绍了设计步骤 ,给出了可同时实现中英文编码的程序设计方法。译码采用 CCD整图读取条码图像 ,用计算机进行图像分析、特征提取 ... 详细信息

介绍了 PDF41 7二维条形码的特点和编码规则 ,详细阐述了用计算机实现其编码的原理和方法 ,并采用具体实例介绍了设计步骤 ,给出了可同时实现中英文编码的程序设计方法。译码采用 CCD整图读取条码图像 ,用计算机进行图像分析、特征提取 ,完成译码的实现方法。实验证明该方法可有效提高译码准确率。

关键词：二维条形码编码译码计算机 PDF417 数据压缩模式

Robust Takagi-Sugeno Fuzzy Control for a Mini Aviation Engine

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Robust Takagi-Sugeno Fuzzy Control for a Mini Aviation Engin...

第二十七届中国控制会议

作者： Shao Jinju,Wei Minxiang,Wen Weidong college of Energy and Power engineering nanjing university of aeronautics and astronautics,nanjing 210016,P.R.China

A nonlinear speed controller is designed using a fuzzy control strategy based on a Takagi-Sugeno（TS） modelling and robust control approach for a mini unmanned helicopter 2-cylinder,two-stroke,electronic fuel injection engine.A physical nonlinear model of the engine is presented and transformed into an uncertain fuzzy TS model to address the nonlinear system ***,a robust nonlinear fuzzy control algorithm is developed via Linear Matrix Inequality（LMI） ,which can provide reference speed tracking despite the presence of torque load disturbances and operating condition *** simu-lations show that the proposed controller can meet the performance requirements for the unmanned helicopter engine use,namely tracking performance,disturbance rejection and robustness.

关键词： Mini unmanned helicopter Engine speed control Takagi-sugeno models Robust control LMI

Guaranteed Cost Control For Networked Control System With Interval Time-varying Delay

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Guaranteed Cost Control For Networked Control System With In...

2009中国控制与决策会议

作者： Gu Zhou~(1,2),Daobo Wang~1,Peng Chen~3,Xiaobo Zhao~2 1.college of automation engineering,nanjing university of{5. astronautics,nanjing 210016,China 2.School of Power engineering,nanjing Normal university nanjing,210042,China 3.Institute of Information and Control engineering Technology,nanjing Normal university,nanjing,210042,China

This paper is concerned with the guaranteed cost controller design of Networked control systems(NCSs) with interval varying *** non-ideal Quality of Servise(QoS) are taken into account by an integrated indexτ(t),which related to data dropout,network-induced delay and error sequence.A new analysis method is provided by using the convexity of the matrix function in deriving the results to avoid the conservatism caused by enlargingτ(t) toτ.Suboptimal guaranteed cost state feedback controller and performance index are developed by solving a set of LMIs based on Lyapunov functional method and a cone complementary linearisation(CCL) *** example and simulation results are given finally to illustrate the effectiveness of our methods.

关键词： Guaranteed cost control Interval time-varying delay Convexity of matrix function

Optimization Design of the Grinding Wheel Topography for High Efficiency Grinding

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厦门大学学报（自然科学版） 2002年第S1期41卷 52-页

作者： FU Yu-can, XU Hong-jun, XU Jiu-hua (college of Mechanical engineering, nanjing university of aeronautics and astronautics, nanjing 210016, China)

On the basis of the measurement of grains distribution on the grinding wheel surface, many experiential models of the grinding wheel topography were set up. But it is pity that few of them yield practical and valuable achievement as yet. The essential reason is that the common foundation of all these models was based on the actual measurement of specific wheel topography. So it didn’t have universal applicability. Considering that the absolute irregular distribution of grains is not the requirement of the grinding process, contrarily it will bring much negative influence to grinding process. By conversely reasoning, a new conception on the relatively regular and reasonable distribution of grains on the wheel surface in accordance with different machining demands is put forward in this paper, and furthermore a creative idea of optimization design of grinding wheel topography in accordance with machining demands and grinding parameters as well as the optimization of grinding parameters in accordance with machining demands and grinding wheel topography is proposed. In the light of this idea, not only the modeling and simulation of grinding process can be really carried out, but also the optimization of grinding process and the estimation of grinding results can be realized straightway. In conclusion, a superabrasive slotted grinding wheel is designed as a practical application of the optimization model and a creep feed deep grinding experiment is carried out to verify the optimization results.

关键词： high efficiency grinding grinding wheel topography

A Hamiltonian Approach to Dynamics and Stabilization of Spacecraft Multibody Systems

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A Hamiltonian Approach to Dynamics and Stabilization of Spac...

第二十七届中国控制会议

作者： Liu Yunping,Wu Hongtao,Fang Xifeng nanjing university of aeronautics&astronautics,college of Mechanical and Electrical{5.,nanjing 210016,P.R.China

The attitude motion equations of spacecraft multibody system take on nonholonomic constraints without external *** dynamic and attitude control of spacecraft multibody system is concerned with nonholonomic constraints system in Hamiltonian *** two point boundary value problem of nonlinear dynamic differential equations can be converted into initial value problem by feedback ***,the control action has a clear physical interpretation by Hamiltonian *** process of model and control is introduced in this *** last,a numerical example by space robot with two arms shows the effectiveness of this approach.

关键词： Spacecraft multibody system Nonholonomic constraints Attitude stabilization Hamiltonian approach

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近空间飞行器多模型非脆弱软切换跟踪控制

四川大学学报（工程科学版） 2011年第6期43卷 190-196页

作者：王宇飞姜长生吴庆宪南京航空航天大学自动化学院南京210016

针对具有强烈非线性、强耦合等特性的变机翼后掠角近空间飞行器,在考虑控制器存在摄动的情况下,设计了多模型非脆弱软切换鲁棒跟踪控制方案。将系统工作空间划分为若干区域,在每一区域建立局部模型,根据跟踪性能指标利用广义系统的方法... 详细信息

针对具有强烈非线性、强耦合等特性的变机翼后掠角近空间飞行器,在考虑控制器存在摄动的情况下,设计了多模型非脆弱软切换鲁棒跟踪控制方案。将系统工作空间划分为若干区域,在每一区域建立局部模型,根据跟踪性能指标利用广义系统的方法设计局部控制器,大大减少了计算量和复杂度,同时减弱了对于待定矩阵的限制,更易于求得可行解,从而降低了保守性。由于控制器在模糊了的边界处进行切换,保证了系统状态在切换过程中的平滑性。最后对近空间飞行器在变机翼后掠角过程中的姿态进行跟踪控制,仿真结果表明了该控制系统具有良好的控制性能。

关键词：近空间飞行器模糊系统鲁棒控制软切换线性矩阵不等式