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971.
针对船舶航向自动舵控制系统的非线性数学模型,应用基于微分几何的反馈线性化方法,将原非线性系统等价为完全可控型线性化模型,然后设计了滑模变结构控制器,并利用模糊控制器实现了滑模趋近律的参数自整定,设计方法简单可行。仿真结果表明,所设计的模糊滑模控制器能够快速准确地跟踪设定航向,并对参数摄动和外界风浪干扰具有很强的鲁棒性,同时消除了系统的抖振现象,优于传统的滑模控制。Abstract: According to the nonlinear model of ship autopilot system and using the feedback linearization procedure of differential geometry,an equivalent,fully controllable and linear model was derived via a homomorphism transformation and a fuzzy reaching law sliding mode controller was designed.The simulation results show that the controller designed here,which is superior to traditional sliding mode control,can track a desired course fast and accurately.It also exhibits strong robustness peculiarity to system uncertainties and avoiding chatting phenomenon. 相似文献
972.
考虑控制器与被控对象之间采用无线传输,且被控对象为非线性模型的一类网络控制系统,对其设计了稳定的模糊控制器。首先基于T-S模糊模型将对象线性化,并利用模糊主导子系统和主导控制规则,简化了模糊控制器的设计。其次,将闭环控制系统方程等效为与无线传输跳数相关的离散切换系统,并证明了闭环系统的稳定性。最后,通过一个仿真例子验证了文中方法的有效性。Abstract: Considering a class of networked control systems using wireless transmission between the controller and the controlled object,and with nonlinear controlled object,the stable fuzzy controller was designed.Firstly,based on T-S fuzzy model,the object was linearized.And the design of the fuzzy controller was simplified by using the fuzzy dominant subsystem and the dominant control rule.Secondly,the equation of the closed-loop control system was equal to the discrete switched system related to the hop count of the wireless transmission.Finally,a simulation example was given to demonstrate the effectiveness of the proposed method. 相似文献
973.
一种截窗查询的多障碍物快速碰撞检测算法 总被引:1,自引:0,他引:1
依赖于地理信息系统的越野路径规划,由于存在大量分布不规律的环境障碍物,严重影响路径规划的计算速度,借鉴截窗查询的思想,给出了基于一维数据结构的矩形截窗查询算法,该算法有效减少了规划过程所需碰撞检测的障碍物个数,大幅提高规划速度,在环境障碍物动态更新的情况下,其性能优于区间树的截窗查询方法。Abstract: Path planning based on GIS is a fundamental problem in many applications. It is the main problem affecting the planning time because of the multi-obstacles in field environment. A novel rectangle windowing query method was proposed in order to improve the compute efficiency of collision free test. The method reduces the numbers of obstacles needed to test and speeds the planning process, and is more suitable with the dynamic environment of obstacles changing than the interval tree method. 相似文献
974.
975.
翼伞系统纵向动力学建模研究 总被引:1,自引:0,他引:1
动力翼伞是一种具有广泛应用价值的独特飞行器,其低速飞行和较大的载荷重量的特点可以使得它成为航空拍摄或军事侦察监视等应用的平台。通过建立简单适用的纵向动力学模型,可以对其速度、姿态等方面的稳定性进行相应的分析。通过推力来控制飞行器的爬升、下降或平飞,起到调整高度的作用。仿真结果表明通过合理的设计载荷与翼伞的质量比、连接绳的长度、翼伞质心与压心的相对位置等影响参数,可以得到较为理想的效果。Abstract: Powered parafoils represent a very unique class of aircraft which has broad applied value. Their slow flight and large payload characteristics make them a practical platform for applications such as aerial screen and military surveillance. The stability of speed and attitude was analyzed by designing a simple and applied longitudinal dynamic model. The climbing, descending or flying straight-and-level of the aircraft were controlled by thrust, which had an effect to adjust the altitude. The simulation results show an ideal purpose can be gained by designing the parameters such as the mass ratio of the payload and parafoil, the length of the link, and the relative position between the center of mass and center of pressure rationally. 相似文献
976.
作战武器任务规划仿真系统原型的开发 总被引:1,自引:0,他引:1
针对复杂虚拟战场环境下的联合作战仿真,设计出了一套仿真方案。利用建模软件Maya、人机交互仿真软件Virtools及程序开发语言C#,开发出了该方案的一个原型。原型采用了根据模型精细度建模、模块化程序设计等优化设计方法。程序运行结果表明,该原型具有模型文件量小、仿真视觉效果佳、程序运行流畅及程序可修改性、可重用性较好等特点,其针对武器装备的作战规划仿真结果为联合作战环境下武器装备的效能评估提供了依据。Abstract: A simulation scheme was designed aiming at joint operations simulation in the comprehensive virtual combat environment which developed the prototype of this scheme, with modeling software Maya, human-computer interaction designing software Virtools, program developing language C#. The prototype applied optimum design methods like modeling according to models' fineness, modular program designing and so on. Based on the program running results, the prototype possessed such good features as lightweight modeling, good visual effects, fluent program operation, better modifying and reusing properties, etc. The simulation results for weapon equipment mission planning provide reference to weapon equipment effectiveness evaluation in the joint operational environment. 相似文献
977.
高速卷绕头是化纤长丝纺丝机的重要单元机,国内之前研究相对较少。采用虚拟产品开发技术进行高速卷绕头新产品开发的技术创新,提高卷绕头产品开发效率。与同类研究类似,在高速卷绕头产品的虚拟开发过程中,集成CAD/CAE系统存在若干技术瓶颈。基于CAD/CAE系统集成方法的对比分析,建立了主模型CAD/CAE集成框架,并在该框架下进行了高速卷绕头锭轴结构参数优化设计,其优化设计的动力性能分析结果验证了基于主模型CAD/CAE集成框架进行高速卷绕锭轴部件虚拟开发的有效性。Abstract: Researches based on the high speed winder, which is a key unit machine for filaments treatment, are relatively rare in China. The techniques of virtual product development (VPD) were applied to improve the new product development of the high speed winder, which would raise the product development efficiency of the high speed winder. Similarly to the research of this kind, in the procedure of developing the virtual product for the high speed winder, there were several key technical problems in the CAD/CAE integrated system. The contrast analysis of the CAD/CAE integrated methods was given; furthermore, the CAD/CAE integrated framework based on master model was built, in which the structural parameters of the high-speed winder chuck was optimized for design. The dynamic characteristics analysis for the optimization design was done; consequently, the result indicates that in the CAD/CAE integrated framework based on master model, the structural parameter optimization of high-speed winder chuck is available. 相似文献
978.
红外探测器是红外成像技术的核心,直接影响着红外成像系统的性能。在分析目标成像尺寸的基础上,详细分析光学弥散、探测器噪声、成像阵列盲元等的形成机理,并进行建模和仿真,最后将这些模型依次叠加。采用此方法得到的仿真图像充分考虑了探测器各种效应的影响,提高了仿真图像的真实性与逼真度,可为红外成像系统的研制及目标检测识别算法提供测试场景与依据。Abstract: Infrared detector, which can directly influence the performance of infrared imaging system, plays a key role in infrared imaging technology. The scale of the target image, the causation of optics dispersion, noise of the detector and blind pixels in the imaging arrays were detailed analyzed. More actual infrared images would be simulated by adding the effects mentioned above to the theoretical image model, because the ill effects were calculated. The simulated images could be used to test infrared imaging system or the algorithm of target detecting and recognition. 相似文献
979.
基于特征值的频谱感知算法仿真研究 总被引:1,自引:0,他引:1
频谱感知是认知无线网络中的一个重要功能,是实现其他功能的基础。研究了新型的基于特征值的感知算法,充分利用随机矩阵的渐近谱分布特性和特征值的收敛特性来设置判决门限,提高感知性能。理论分析和仿真结果均表明,新型算法性能明显优于典型的能量检测算法,克服了能量检测算法的噪声不确定性问题。Abstract: Spectrum Sensing is an important function in the cognitive radio networks.A new eigenvalue-based detection scheme for spectrum sensing was studied,and decision thresholds were set to have good performance by using the property of asymptotic spectrum distribution and convergence of maximum eigenvalue of random matrices.Theoretical analysis and simulations results show that the new detection scheme can obviously outperform the classical energy detection,and overcome the noise uncertainty problem. 相似文献
980.
以提高汽车行驶平顺性和操纵稳定性为出发点,建立了汽车ASS与EPS的整车动力学模型,提出了一种汽车ASS与EPS集成控制的方法。分别设计了ASS子系统模糊控制器与EPS子系统模糊控制器,利用分层协调控制思想建立了上层协调控制器,对两个子系统进行协调控制。仿真结果表明:采用分层协调控制策略控制的ASS与EPS集成系统可使车身垂直加速度、车身俯仰角、横摆角速度、车身侧倾角等性能参数得到优化,汽车行驶平顺性和操纵稳定性有明显改善,提高了整车综合性能。Abstract: Vehicle dynamics model of ASS and EPS was built.A coordination control method of vehicle ASS and EPS was presented to improve vehicle ride performance and handling stability.ASS controller and EPS controller were designed separately.The controller of ASS was designed using fuzzy logic control theory and the EPS system was designed using fuzzy logic control theory too.In order to coordinate the two subsystems,an upper coordination controller was set up based on an idea of delaminating control.The simulation results show that layered coordination control strategy can optimize the vehicle performance parameters and the vehicle integrated performance is improved obviously. 相似文献