共查询到20条相似文献,搜索用时 78 毫秒
1.
针对前期研究的双层直线时栅位移传感器测量误差成分中四次谐波较大,影响传感器测量精度的问题。根据双层激励线圈的结构特点,提出了一种双层反向倾斜线圈结构的直线时栅位移传感器设计方案。通过构建双层反倾线圈产生磁场的数学模型,分析了双层反向倾斜线圈的磁场状态,并利用电磁场有限元仿真分析双层反倾线圈直线时栅位移传感器中倾斜大小和动定尺之间的气隙对测量误差与误差谐波成分的影响,确定了最优化的设计参数。采用PCB(Printed Circuit Board)工艺研制了78个节距大小的传感器样机并进行了精度测试。实验结果表明,双层反倾斜线圈结构对原双层直线传感器中误差四次谐波抑制效果显著,在同样设置条件下,将原测量误差成分中四次谐波从40μm抑制到7μm,抑制效果达到82.5%。最终经过误差修正后的传感器对极内精度达到±13μm。 相似文献
2.
针对绝对式位置传感器编码复杂和加工工艺要求较高的问题,本文提出了一种基于平面磁场的双列结构绝对式时栅位移测量新方法.研究采用两列不同极距的"几"字型结构定尺绕组产生运动磁场,通过动尺电磁感应方式构造两列空间位移信号,建立两列空间位移信号相位差与运动位移的线性映射关系,通过粗通道定位和精通道测量实现绝对式位移测量.通过理论推导和模型仿真分析证明了绝对式位移测量方法的正确性.制作了PCB传感器样机进行了实验研究,结果表明传感器通过修正后定位精度可达到±9.6μm.此绝对式时栅位移传感器不仅具有结构简单,成本低廉等优势,还有效克服了传统绝对式位置传感器编码复杂和加工工艺要求较高的问题,可应用于复杂机电系统实现精密绝对定位,具有重要应用价值. 相似文献
3.
为了解析安装参数与测量精度的关系,根据纳米时栅的基本测量原理,构建出与动、定尺间距d0和正对面积变化量ΔS相关的数学模型.通过理论推导,分析了动尺在yz平面倾斜、xy平面偏转时会导致两路驻波幅值不等、相位偏移,从而给测量结果带来二次误差.实验结果表明通过调整动尺在yz平面与xy平面上的安装,对极内原始误差由4.86μm降低至0.84μm,证明动尺在yz平面倾斜、xy平面偏转为产生二次误差的主要原因.在行程200mm测量范围内,传感器误差峰峰值为400nm.实验结果验证了理论分析的正确性,该分析为传感器结构参数优化和实验方法的改进提供了有力的支撑,为进一步提升传感器精度提供了可靠的理论依据. 相似文献
4.
时栅位移传感器采用时空坐标转换理论,可在低加工精度条件下实现角位移的高精度测量,现已应用于高精度数控转台控制系统中。原有的场式时栅位移传感器借鉴电机结构,通过转子线圈感应旋转磁场产生电行波,再通过滑环引出。为了消除滑环结构,进一步降低成本、提高传感器抗干扰能力,通过磁导调制方法产生两路驻波并合成电行波,采用两路驻波磁路分离式结构,设计去除转子绕线的磁导调制型时栅位移传感器。利用电磁仿真软件对传感器的各项参数进行仿真优化,传感器仿真电行波幅值变化6.1%;采用光栅进行精度标定实验,测量精度达到-2.7″~+2.2″。 相似文献
5.
SMT贴片印刷中,钢网的平整度是影响贴片印刷质量的重要因素。钢网平整度是通过测量钢网四角和中间位置的表面张力确定。表面张力测量计分为指针式和数字式。目前尚无SMT钢网张力在线测量系统。设计一款基于容栅式位移传感器的表面张力检测系统,对于提高贴片印刷的质量,具有实际应用意义。容栅式位移传感器设计为定尺和动尺。表面张力引起动尺的微小位移,在定尺形成与位移关联的电容变化。GC7626控制器将定尺电容变化转成数字信号,精度为1N/cm。采用STM32F103C8T6微控制器为主控系统,STM32F103C8T6读取GC7626的张力数据,以及存储有钢网信息的RFID数据,并将数据通过蓝牙模块传输给上位机(手机)。上位机(手机)上设计有APP软件,对张力数据进行处理。系统已经成功应用工业生产中,实现了钢网张力的在线检测和智能化管理。 相似文献
6.
现有磁场式时栅位移传感器暴露出机械加工齿槽等分性差和线圈绕制参数一致性差,导致耦合磁场形成的电信号质量较差的问题.针对以上问题,提出了一种以圆形截面铁磁材料替代传统类矩形截面铁磁材料构建耦合磁场形式的传感器设计方法,该方法采用标准件作为基本阵列导磁单元,并以定制的精密线圈绕组设计一种新型的变磁阻式时栅位移传感器.文中首先利用有限元软件ANSYS Maxwell对理论模型的可行性进行了仿真验证,然后通过精度实验获取了误差范围在±1.3"内的误差曲线,仿真与样机实验验证了新型传感器设计方案的可行性.该方法的应用规避了传统的线切割开槽绕线的机械加工形式,可以在有效提高电信号质量的同时大大提高了时栅的生产效率,有利于时栅位移传感器产品化进程的推进. 相似文献
7.
8.
9.
燃气轮机转子叶尖间隙对发动机性能有重要影响,为实现其精密测量,首先,根据光纤对光强耦合原理得到了双圈同轴光纤束的光强调制特性函数;接着,分析了倾角变化对反射式光纤位移传感器测量特性的影响;然后,完成了间隙测量系统设计;最后,通过静态测量实验和不同转速下的动态测量实验验证了所设计系统的性能;实验结果表明:所设计传感器线性测量范围为2mm,测量系统动态性能较好。 相似文献
10.
为了满足伺服系统位移传感器安装空间小、测量范围大及高可靠性的需求,对串联双冗余高精度差动变压器式位移传感器的设计技术进行了研究。阐述了差动变压器式位移传感器的原理和结构,介绍了串联双冗余差动变压器式位移传感器抗电磁耦合干扰、结构加固以及专用变换电路的设计方法;为提高线性度,在有限的径向安装空间,设计阶梯式线圈绕制方法,通过试验找出了最佳绕线参数,使线性度达到0.1%以上,满足了系统的高精度和高可靠性要求。 相似文献
11.
针对现有磁场式时栅角位移传感器原始测量精度低且误差成分复杂等特点,提出一种基于遗传算法的误差参数辨识与补偿方法,该方法根据时栅误差数学模型抽象出适应于生物遗传法则的遗传算法模型。首先将磁场式时栅误差辨识参数的样本数据进行针对性训练,并设置约束条件,然后利用遗传算法的“部分可观测黑箱性”特点进行数据样本迭代,并与时栅误差参数建立的目标函数寻求最佳逼近,以此完成误差参数的最优估计和误差曲线的最佳补偿。实验研究表明,采用遗传算法建立的时栅误差参数辨识模型辨识准确,对时栅误差成分中最主要的二次、四次误差有明显减少作用,其中二次误差减小66.67%、四次误差减小54.05%;与此同时,对一次误差及高频误差成分也有不同程度的抑制。 相似文献
12.
为了保障时栅传感系统稳定性、提高测量精度,提出一种基于ELMAN神经网络和灰色模型组合预测的时栅信号处理系统健康状况预测方法。采用克朗巴哈系数法分析确定激励信号幅值、相位为预测参数。基于ELMAN神经网络及灰色模型,结合加权-比例-平均思想实现了组合模型建模。根据系统运行实际,以幅值和相位的相对误差为指标,制定健康诊断标准。实验结果表明,组合模型预测结果的相对误差、预测均方差和相对系数分别为0.101 6、0.011 9和0.988 5,预测误差小、相关性高。经健康诊断标准判定,健康状况预测结果与电路实际相符。该健康状况预测方法预测精度高,且明显高于单一模型,满足提前准确获悉电路系统健康状况的要求。 相似文献
13.
一维纳米材料与微结构结合的纳器件制造过程,实现了微纳加工工艺上的创新升级,有可能突破微米级器件的性能极限。首先利用传统的硅微加工技术,在综合性能优异的聚酰亚胺PI(Polyimide)薄膜上制作金(Au)微电极,形成排列有序的平行电极对;然后通过交流介电电泳的方法在微电极对间实现单壁碳纳米管SWNTs(Single-Walled Carbon Nanotubes)一维定向排布;接着采用区域选择性电沉积技术定域沉积Au压覆SWNTs,改善SWNTs与电极的接触特性。最后,针对基于SWNTs的柔性微纳传感器进行了力电特性测试。结果表明:在环境温度为(23±5)℃,湿度为65±15%RH,0.1 V工作电压下,压阻因子约为443,精度约为5.16%。上述研究结果在柔性微纳器件的制作方面显示了一定的应用前景,为实现超微型化和高功能密度化的柔性器件铺平道路。 相似文献
14.
15.
The topology control strategies of wireless sensor networks are very important for reducing the energy consumption of sensor nodes and prolonging the life-span of networks. In this paper, we put forward a minimum-energy path-preserving topology control (MPTC) algorithm based on a concept of none k-redundant edges. MPTC not only resolves the problem of excessive energy consumption because of the unclosed region in small minimum-energy communication network (SMECN), but also preserves at least one minimum-energy path between every pair of nodes in a wireless sensor network. We also propose an energy-efficient reconfiguration protocol that maintains the minimum-energy path property in the case where the network topology changes dynamically. Finally, we demonstrate the performance improvements of our algorithm through simulation. 相似文献
16.
17.
18.
19.
Badong Chen Yu Zhu Jinchun Hu Zengqi Sun 《International Journal of Control, Automation and Systems》2009,7(2):157-164
Traditional filtering theory is always based on optimization of the expected value of a suitably chosen function of error,
such as the minimum mean-square error (MMSE) criterion, the minimum error entropy (MEE) criterion, and so on. None of those
criteria could capture all the probabilistic information about the error distribution. In this work, we propose a novel approach
to shape the probability density function (PDF) of the errors in adaptive filtering. As the PDF contains all the probabilistic
information, the proposed approach can be used to obtain the desired variance or entropy, and is expected to be useful in
the complex signal processing and learning systems. In our method, the information divergence between the actual errors and
the desired errors is chosen as the cost function, which is estimated by kernel approach. Some important properties of the
estimated divergence are presented. Also, for the finite impulse response (FIR) filter, a stochastic gradient algorithm is
derived. Finally, simulation examples illustrate the effectiveness of this algorithm in adaptive system training.
Recommended by Editorial Board member Naira Hovakimyan under the direction of Editor Jae Weon Choi. This work was supported
in part by the National Natural Science Foundation of China under grants 50577037 and 60604010.
Badong Chen received the B.S. and M.S. degrees in Control Theory and Engineering from Chongqing University, Chongqing, China, in 1997
and 2003, respectively, and the Ph.D. degree in Computer Science and Technology from Tsinghua University, Beijing China, in
2008. He is currently a Postdoctor of the Institute of Manufacturing Engineering, Department of Precision Instruments and
Mechanology, Tsinghua University, Beijing, China. His research interests are in signal processing, adaptive control, and information
theoretic aspects of control systems.
Yu Zhu received the B.S. of Radio Electronics in 1983 at Beijing Normal University, and the M.S. of Computer Applications in 1993,
and the Ph.D. of Mechanical Design and Theory in 2001 at China University of Mining & Technology. He is now a Professor of
the Institute of Manufacturing Engineering of Department of Precision and Mechanology of Tsinghua University. His current
research interests are parallel machanism and theory, two photon micro-fabrication, ultra-precision motion system and motion
control.
Jinchun Hu received the Ph.D. in Control Science and Engineering from Nanjing University of Science and Technology, Nanjing, China,
in 1998. Since then, he has been a postdoctoral researcher in Nanjing University of Aeronautics and Astronautics in 1999 and
Tsinghua University in 2002 respectively. His research interests are in flight control, aerial Robot and intelligent control.
Dr. Hu is currently an Associate Professor of the Department of Computer Science and Technology of Tsinghua University, Beijing,
China.
Zengqi Sun received the B.S. degree from the Department of Automatic Control, Tsinghua University, Beijing, China, in 1966 and the Ph.D.
degree in Control Engineering from the Chalmas University of Technology, Sweden, in 1981. He is currently a Professor of the
Department of Computer Science and Technology, Tsinghua University, Beijing, China. He is the author or coauthor of more than
100 paper and eight books on control and robotics. His research interests include robotics, intelligent control, fuzzy system,
neural networks, and evolutionary computation. 相似文献