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本文阐述了基于MEMS的微型无线姿态监测系统平台,可对微型载体的姿态进行测量和远距离传输,并进行后续的姿态控制分析和误差噪声分析.系统由自行研制的MEMS方位水平仪和微型无线数据传输系统组成,MEMS方位水平仪实现微型载体的全姿态测量,俯仰角测量范围-90°~90°,滚转角测量范围-180°~180°,航向角测量范围0°~360°,测量角度误差小于0.5°,灵敏度为0.1°;数据传输单元,有效质量为35g、功耗低,体积为40x60x30mm3,误码率达到106,传输有效半径达1.5km;平台通过微型飞行器三维模拟转台,进行了对系统监控的可靠性仿真测试,数据表明MEMS微型无线监测系统可应用于对微型载体的姿态实时监测. 相似文献
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高精度航天器对指向精度有极高的要求,飞轮是卫星姿态控制环节中不可或缺的执行部件,在研制和装备过程中,不可避免地具有微量的偏心或动不平衡,在姿态机动和稳定控制的过程中,飞轮的旋转会产生干扰力。将动静不平衡质量作为航天器的一部分,推导出完整航天器动力学姿态方程,进行动力学仿真,并根据完整的姿态动力学方程简化分析仿真结果。研究发现动静不平衡质量在飞轮高速转动时,对姿态均有影响,动不平衡质量对姿态的影响与安装位置关系很小,而静不平衡质量呈现线性关系,且两者对姿态的影响满足线性叠加。单轴转动时,指向精度的长周期变化只与飞轮的固有特性有关,与转速的大小无关。多轴转动时,姿态会振荡或发散,与初始相位有关;但对姿态的影响不满足单轴转动的叠加。 相似文献
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月球软着陆轨道优化方法比较研究 总被引:1,自引:0,他引:1
月球软着陆轨道优化问题是一非线性、终端时间自由且带有控制约束的最优控制问题.月球探测器软着陆轨道优化的难点在于怎么处理自由的终端时间,如何把非线性的控制问题转换为易于处理的优化问题.本文介绍了月球探测器的几种软着陆方式和月球探测器轨道的多种优化方法,对各种优化算法进行了一个大概的分类,并对各种优化算法的优缺点进行了分析比较.进而,总结了解决月球探测器软着陆轨道优化问题难点的几种有效方法,为未来我国的月球软着陆工程提供了参考. 相似文献
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为研究大型星载SAR天线的高稳定度指标分配问题,根据天线在轨运行的实际环境设计了三种仿真工况,运用ADAMS对SAR卫星天线进行多体动力学分析,并提出运用概率法对指向精度进行合理分配。结果表明:在具有相同有效载荷且距离天线位置相对较近的部位施加扰动对SAR天线的指向精度影响较大,且影响程度由大到小依次为:隔振器扰动、CMG调姿扰动、SADA扰动。三个视角对天线指向精度的影响程度由大到小依次为:俯仰角、方向角、距离角。提高隔振器的隔振性能,减少有效载荷的扰动对卫星天线指向精度的影响,在多种成像模式切换的过程中加强对俯仰角的控制,可以有效地提高SAR卫星天线的成像质量,并为卫星总体选择合适型号的调姿机构提供帮助。 相似文献
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空间站大柔性太阳电池翼驱动装置的滑模伺服控制 总被引:1,自引:0,他引:1
针对空间站大柔性太阳电池翼高稳定对日跟踪驱动控制问题,提出了一种带运动规划和振动抑制的非线性快速终端滑模伺服控制方案。推导了太阳电池翼驱动状态方程、永磁同步电机动力学模型,同时考虑驱动装置传动间隙、静/动摩擦力矩切换等非线性传动特性,在动力学建模基础上设计高次样条运动规划、位置环积分分离调节器、速度环快速终端滑模变结构调节器的组合控制系统。通过对太阳电池翼对日跟踪过程的仿真校验,表明设计的控制方案可实现大惯量、超低频太阳电池翼较高的驱动速度稳定度和较好的跟踪精度。 相似文献
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基于智能模糊控制策略的有源消声 总被引:3,自引:0,他引:3
有源消声是一种有效的低频噪声控制方法,由于空间有源消声过程具有时变性和非线性,传统的自适应算法不能进行很有效的控制。本文采用智能模糊控制策略,建立了基于智能模糊控制策略的有源消声系统,通过实验与传统自适应控制算法的消声效果作对比分析,证明智能模糊控制器不但控制速度快,易于实现,而且消声效果明显优于后者,具有较大的应用推广价值。 相似文献
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This paper reviews robotic position and force control techniques. The existing fundamental force control algorithms are compared and discussed,including explicit / implicit control,stiffness control,impedance / admittance control,and hybrid position / force control. This work is intended to give a basic guidance for understanding and utilization of the fundamental robotic control algorithm. 相似文献
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噪声主动控制技术目前已用增加双隔板结构对声音进行衰减。在这项研究中,声音穿过双隔板进入房间有三种控制途径:在双隔板的空气间隙中应用声控源(腔控),在辐射板上应用振动控制源(板控),在接收房间内应用声控源(房控),都进行了实验研究和相互比较。每种方法中涉及到的机械装置都有例子,有效减少噪声的状况都经过考查。结果表明,每种方法(腔控、板控和房控)的模态重叠和涉及到的机械装置是两个重要的因素,它决定了每种方法有的有效性。 相似文献
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Douglas C. Montgomery J. B. Keats Mark Yatskievitch William S. Messina 《Quality and Reliability Engineering International》2000,16(6):515-525
Feedforward control is a particular form of engineering process control. If a known input variable zt can be measured and appropriate relationships built between the input variable, a compensatory variable xt, and the desired output yt, then a feedforward control system can be developed. Using feedforward control, we show under both sudden jump shifts and trends in the mean of the input and compensatory variables that the use of statistical process monitoring tools, such as the exponentially‐weighted moving average and the cumulative sum (CUSUM), significantly reduces variability in both the output variable and the controller relative to the use of feedforward control alone. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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This paper provides a survey of the main advanced control techniques currently adopted in factory automation. In particular, it focuses on five classes of control approaches, namely: model-based control, control based on computational intelligence, adaptive control, discrete event systems-based control and finally event-triggered and self-triggered control. A particular focus is put on the most significant and recent contributions in these areas with attention to their application in the factory automation domain. Finally, open issues, challenges and the requirements of further research efforts for each class are pointed out. 相似文献
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In this paper, we describe the development of the variable dimension and variable sample size T2 control chart (VSSVDT2), which is an enhancement of the variable dimension T2 chart (VDT2). In the VDT2 control chart, the number of variables that are measured to compute the T2 statistic is made variable. Some of the variables are easy or inexpensive to measure and are always monitored. The variables that are more difficult or expensive to measure are measured only when the T2 value from the previous sample exceeds a specified threshold. The VDT2 control chart performs well for moderate and large shifts in the mean vector. However, its performance for small shifts is poor. To improve the chart’s performance in detecting such shifts, we propose the application of the variable sample size technique to the VDT2 control chart, resulting in the VSSVDT2 control chart. To promote the use of the VSSVDT2 chart, a user-friendly software has been developed, which the final user can use to find the best parameters of the VSSVDT2 chart for a particular process. 相似文献
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The idea of a variable sampling interval with sampling at fixed times (VSIFT) has been presented by Reynolds. This paper extends this idea to the other two adaptive ―X charts: the variable sampling rate with sampling at fixed times (VSRFT) ―X chart and the variable parameters with sampling at fixed times (VPFT) ―X chart. The VSIFT, VSRFT and VPFT ―X charts are inclusively called the adaptive with sampling at fixed times (AFT) ―X charts in this paper. The control scheme and the design issue are described and discussed for each of the AFT ―X charts. A comparative study shows that the AFT ―X charts have almost the same detection ability as the traditional adaptive ―X charts. However, from the practical viewpoint, the AFT ―X charts are considered to be more convenient to administer than the traditional adaptive ―X charts. Overall, this paper advances the application of ‘sampling at fixed times’ to the adaptive ―X control charts. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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自适应前馈振动主动控制的参数选择与稳定性 总被引:2,自引:2,他引:2
基于自适应滤波的自适应前馈振动主动控制系统的等效传递函数,对控制系统的参数选择及稳定性进行研究。将受控结构模型变换到Z域,推导控制系统的等效Z域传递函数,把朱利(Jury)稳定判据引入控制系统的稳定性研究,探讨采样频率、滤波器阶数、参考信号等对系统稳定性的影响,得出了具有指导意义的结论 相似文献
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变风量空调系统控制方法及试验台搭建 总被引:2,自引:0,他引:2
介绍了变风量(VAV)空调系统的特点,分析了VAV系统末端控制、AHU等控制方法,着重对末端控制方法与AHU控制方法进行了多种形式的比较,并以实际工程实例加以说明. 相似文献