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1.
研究了一种新的空天飞行器鲁棒自适应轨迹线性化飞行控制系统设计方案。利用单隐层神经网络的逼近能力在线估计系统中存在的不确定性,神经网络输出用以抵消不确定性对轨迹线性化方法控制性能的影响。鲁棒自适应控制器用以克服逼近误差,并使闭环系统具有更好的性能。严格的理论证明表明,给定的自适应调节律能够保证闭环系统跟踪误差最终收敛至任意小紧集。空天飞行器高超声速飞行条件下的仿真结果表明,即使在很恶劣的条件下,新方法仍然表现出很好的响应性能。  相似文献   

2.
飞行器大包线鲁棒飞行控制律设计   总被引:1,自引:0,他引:1  
对于飞行器随环境改变而参数变化范围较大的问题,研究采用鲁棒控制方法进行控制律设计。重点研究被控对象不确定的建模问题。将飞行器参数变化视为飞行器对象的不确定性,分别给出了时域和频域两种不确定性的建模方法。采用时域状态空间模型不确定性的线性分式变换描述方法,对某飞行器进行了大包线范围的μ综合鲁棒控制律设计。设计仿真结果表明,控制系统不但具有鲁棒稳定性,而且具有鲁棒性能。  相似文献   

3.
殷婷婷  贾方秀  于纪言  王晓鸣 《兵工学报》2019,40(12):2425-2432
针对双旋弹丸舵翼滚转位置系统存在非线性摩擦、不确定性参数以及时变扰动等问题,提出一种基于连续可微LuGre摩擦模型的鲁棒自适应控制策略。以基于永磁同步发电机为电磁执行机构的舵翼滚转位置控制系统为研究对象,建立包含改进摩擦模型的系统非线性数学模型。通过对未建模扰动的上界进行自适应估计,在控制器中设计扰动补偿鲁棒反馈项将其补偿,降低扰动对控制性能的影响。对系统不确定性参数、摩擦状态量进行在线自适应估计,并结合摩擦补偿设计自适应控制律,降低系统对参数不确定性和非线性摩擦的敏感度。通过Lyapunov稳定性理论证明了闭环系统的全局稳定性。仿真结果表明:该方法能准确地对模型参数、非线性摩擦状态以及扰动进行估计和补偿,具有控制精度高、稳定性好和鲁棒性强等优点。  相似文献   

4.
胡如夫  崔仲华  李普  陈南 《兵工学报》2006,27(1):111-115
以在工程中普遍存在的封闭空间结构一声耦合系统为对象,基于鲁棒结构奇异值理论,建立了结构一声耦合系统鲁棒主动控制模型,提出了设计鲁棒μ-synthesis。控制器的方法:通过引入虚拟的不确定块,将耦合系统响应性能的问题转化为广义系统的稳定鲁棒性问题,采用标准D-K迭代法求解该增量系统的稳定鲁棒控制器。封闭空间结构一声耦合系统的控制仿真表明,同鲁棒H∞控制结果相比,μ-synthesis方法对模型不确定性具有良好的稳定鲁棒性和性能鲁棒性。同以往的研究相比,新意在于应用μ-synthesis方法设计了结构一声耦含系统鲁棒控制器,以克服H∞控制器的不足。  相似文献   

5.
飞行器倾斜转弯的非线性鲁棒控制   总被引:1,自引:0,他引:1  
利用自适应控制中回代设计的思想,结合基于微分几何的非线性化反馈线性化方法,研究了一类非线性不确定性系统的鲁棒控制器设计方法,得到了带系统不确定性补偿项的控制规律,并证明了闭环系统的一致肋介稳定性不对一类飞行器的非线性运动模型进行了适当的处理,设计了倾斜转弯运动的非线性鲁棒控制器,并进行了闭环仿真计算,结果表明,控制器对系统不确定性的抑制效果良好。  相似文献   

6.
为解决有人与无人车辆编队中,有人领航车紧急加减速和紧急转向控制输入对无人车跟踪控制的扰动问题,设计了一种参数自优化的有人与无人车辆编队鲁棒模型预测控制算法。通过采集分析历史数据确定控制器扰动的噪声极值,并经过适度放缩得到其鲁棒边界。设计抑制该扰动的局部反馈鲁棒控制器,并通过贝叶斯优化的方法实现鲁棒边界等控制器参数自优化。基于混合整数线性优化的方法预测有人领航车未来轨迹,并设计鲁棒模型预测控制器实现无人车对有人领航车的跟踪控制。仿真和实车试验结果表明:所设计的鲁棒模型预测控制器在跟踪精度方面相比于传统模型预测控制器有明显的提升;同时该控制器有效地抵抗了来自有人领航车紧急加减速和紧急转向控制输入、无人跟随车系统模型不确定性和外部环境的扰动,振荡情况明显改善,提高了系统的鲁棒性。  相似文献   

7.
低速旋转尾翼稳定弹飞行过程中存在着气动交联、惯性交联和控制交联,为了实现稳定飞行,有必要进行解耦控制器设计。鉴于模型预测控制方法虽然具有较好的解耦能力和对建模精度要求不高的优点,但存在计算量大的问题,为此提出一种基于指令滤波器的离线模型预测控制方法。通过离线求解控制参数阵和在线查表应用的方式,将大量计算工作转为离线进行,以满足实时控制需求。将指令状态和系统输出跟踪误差积分引入预测模型中,充分利用被控对象和指令模型的动态特性,使得离线求解的控制参数阵能够较好地应对指令信号的变化。基于旋转尾翼稳定弹姿态控制进行仿真,对算法的有效性进行了验证,结果表明所设计的控制器能够确保飞行指令的稳定跟踪。  相似文献   

8.
高超声速飞行器通常结构整体柔度大、飞控系统权限大、飞行环境复杂、气动加热严重,极易导致由结构、气动、热和控制等耦合引起的气动伺服弹性稳定性问题。由于建模复杂、不确定性多及参数摄动影响,传统的稳定性分析方法不适用分析飞行器气动伺服弹性系统的鲁棒稳定性。利用线性分式变换,考虑多种参数摄动,由子系统到整个闭环系统依次建立气动伺服弹性状态空间模型,并应用结构奇异值?方法分析了系统的鲁棒稳定性。分析结论表明了该建模方法的有效性以及?方法在飞行器气动伺服弹性鲁棒稳定性分析中的应用前景。  相似文献   

9.
邵锡军  杨成梧 《兵工学报》2001,22(3):312-316
系统的状态估计在航迹互联, 机动目标跟踪过程中有着重要的作用.本文研究了一类方差约束的不确定Delta算子系统的鲁棒滤波器的设计问题,通过求解修正的Riccati方程得到了不依赖于不确定性的鲁棒滤波器, 使得对所容许的不确定性参数,系统的每个状态的估计方差不大于预先给定值;并讨论了期望的滤波器存在的条件.最后给出一个例子来验证所给方法的有效性.  相似文献   

10.
火箭俯仰角控制的H混合灵敏度设计   总被引:15,自引:0,他引:15  
从滤波器设计出发提出了一种实用的构造挠性模型摄动界函数的方法,并分析了鲁棒性能加权函数的频带特性、带宽和增益与系统性能之间的关系.以火箭俯仰角控制为例详细分析了在使用加性不确定性描述系统挠性摄动和考虑扰动频谱的情况下如何通过H∞设计混合灵敏度控制器来获得系统的鲁棒稳定性和相应的鲁棒性能.  相似文献   

11.
Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.  相似文献   

12.
The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.  相似文献   

13.
Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.  相似文献   

14.
By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.  相似文献   

15.
By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.  相似文献   

16.
The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.  相似文献   

17.
For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.  相似文献   

18.
An expression for estimating the aeroheating on a warhead nose at different supersonic speeds is proposed by incorporating CFD (computational fluid dynamics) and the least-square method. Compared with the traditional estimation formula, the expression is more accurate, convenient and can be used in the optimized design of warheads. The error from the result obtained in the test of a ball cartridge flight is less than 3 %. It satisfies the engineering requirements.  相似文献   

19.
The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent "explosion of terms". Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.  相似文献   

20.
The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.  相似文献   

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