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由于目前在小型无人机执行器故障诊断中存在着智能化程度较低,容易受到人为因素干扰,从而出现故障漏检等问题,难以满足小型无人机对飞行安全的要求。为此,本文提出一种基于多维数据关联规则挖掘(Multidimensional Data Association Rules Mining: MDARM)和VxWorks操作系统的小型无人机执行器故障诊断方法,通过建立执行器内部传感器测量的温度、压力、流速、力矩等相关变量的历史数据库,并对这些数据进行预处理,以避免带来噪声污染,并利用可测量参数与不可测量参数之间的关联性,建立故障诊断知识库,避免了诊断过程中的人为因素干扰,实现小型无人机执行器故障的精准测量。实验结果证明,这种方法能够有效地提高故障准确率64.7%,对小型无人机执行器的智能诊提供有效指导,应用前景广阔。 相似文献
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旨在研究无线传感器与执行器网络(WSANs)中节点失效情况下恢复执行器(actor)节点服务的算法. 首先说明了WSANs中的实时覆盖模型, 证明WSANs覆盖恢复问题是NP难问题, 给出了近似求解方案. 在此基础上, 提出了一种基于六边形蜂巢结构的移动容错算法HMFR用于恢复失效actor节点, HMFR 算法在限制网络初始部署的条件下拥有很好的性能. 通过实验与现有的恢复算法进行比较, 发现HMFR算法在actor覆盖sensor节点数和移动距离方面有更好的性能. 相似文献
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CONTINUUM TOPOLOGY OPTIMIZATION FOR MONOLITHIC COMPLIANT MECHANISMS OF MICRO-ACTUATORS 总被引:2,自引:0,他引:2
Luo Zhen Du Yixian Chen Liping Yang Jingzhou Karim Abdel-Malek 《Acta Mechanica Solida Sinica》2006,19(1):58-68
A multi-objective scheme for structural topology optimization of distributed compliant mechanisms of micro-actuators in MEMS condition is presented in this work, in which mechanical flexibility and structural stiffness are both considered as objective functions. The compliant micro-mechanism developed in this way can not only provide sufficient output work but also have sufficient rigidity to resist reaction forces and maintain its shape when holding the work-piece. A density filtering approach is also proposed to eliminate numerical instabilities such as checkerboards, mesh-dependency and one-node connected hinges occurring in resulting mechanisms. SIMP is used as the interpolation scheme to indicate the dependence of material modulus on element-regularized densities. The sequential convex programming method, such as the method of moving asymptotes (MMA), is used to solve the optimization problem. The validation of the presented methodologies is demonstrated by a typical numerical example. 相似文献
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交联液晶高分子兼具液晶的各向异性和高分子网络的弹性,并且具有优异的分子协同作用.在交联液晶高分子中引入光响应基团,例如偶氮苯后,即可赋予其光致形变性能,利用分子协同作用可以将光化学反应引起的分子结构变化放大为宏观形变,从而将光能直接转化成机械能.通过合理的分子结构和取向设计可以使液晶高分子产生诸如伸缩、弯曲、扭曲、振动等多种形式的光致形变,并用于各类光控柔性执行器件的构筑,在人工肌肉、微型机器人、微量液体操控等领域呈现出独特的优势和广阔的应用前景.本文总结和评述了光致形变液晶高分子的研究,包括材料结构对光致形变性能的影响、新型可加工光致形变材料的研究、利用可见光和近红外光触发形变的策略,以及光致形变液晶高分子微执行器在微量液体操控中的应用,最后展望了该领域的发展方向. 相似文献
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An optimal vibration control strategy for partially observable nonlinear quasi Hamiltonian systems with actuator saturation is proposed. First,a controlled partially observable non-linear system is converted into a completely observable linear control system of finite dimension based on the theorem due to Charalambous and Elliott. Then the partially averaged It stochastic differential equations and dynamical programming equation associated with the completely observable linear system are derived by using the stochastic averaging method and stochastic dynamical programming principle,respectively. The optimal control law is obtained from solving the final dynamical programming equation. The results show that the proposed control strategy has high control effectiveness and control effciency. 相似文献
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《数学的实践与认识》2013,(20)
研究了不确定时不变中立型混杂时滞线性系统的鲁棒H_∞可靠控制问题.考虑系统出现执行器混合故障,采用状态反馈,基于线性矩阵不等式(LMI)给出了闭环系统渐近稳定且具有H_∞性能的一个充分条件.同时,给出了对应H_∞可靠控制器的设计方法.最后,仿真数例说明了所给方法的可行性. 相似文献
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针对现有气动式机器人力控末端执行器存在力控精度低和响应慢等缺点, 提出一种非对称气电混合式力控末端执行器, 采用变参数PID控制器对非对称气缸的气动力与永磁直线同步电机的电磁力进行协调控制, 实现机器人连续接触式作业中接触力的实时补偿与精确控制. 通过对气动系统、永磁电机和控制器等进行建模与仿真分析, 研究其控制特性与力-位移特性. 仿真结果表明, 相比气动力控系统, 气电混合式力控系统可有效消除摩擦力与跟随误差等引起的滞环和爬行现象, 控制特性最大误差由9.2N(2倍最大静摩擦力+动静摩擦力差值)减小至1N, 其力-位移特性最大误差由9.6N(2倍动摩擦力+气动力波动)也减小至1N, 提高了力控精度, 可提升机器人连续接触式作业质量. 相似文献