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1.
在流体力学的研究领域,流体自由面的变化是一种非常重要的物理现象.针对自由面的形变位移,研制一套双频激光相位光电检测系统.将光学干涉技术与相位计相结合,实时获得相位计输出的反映流体表面形变的信号.本文详述了此双频激光相位光电检测系统的原理和装置.通过高精度PI步进电机驱动物体移动,标定系统的性能特性.应用激光位移传感器验证该系统的精度,同时分析环境对干涉测量系统的影响.将该系统应用于浮力热毛细对流自由面形变测量中,获得有意义的实验结果.  相似文献   

2.
文中提出一种在场景自然特征识别基础上采用关键帧匹配的增强现实跟踪注册算法,实现了基于计算机视觉的户外大场景范围内的实时跟踪定位.算法针对关键帧匹配中的宽基线特征匹配问题,提出采用随机树的模式分类方法实现场景自然特征的离线训练和在线实时精确匹配.同时采用Kalman滤波器对参数估计结果进行平滑解决视觉跟踪定位中的抖动问题.以该算法为核心构建出基于视频透视式头盔显示器的移动增强现实系统,并将其成功应用于圆明园大水法景观的数字重现.真实场景实验验证表明,该方法具有实时、鲁棒的优点,适用于户外跟踪定位.  相似文献   

3.
根据煤矿环境的特点,提出了一种基于Zigbee技术的适用于煤矿巷道多参数采集的无线传感器网络检测系统。该系统利用多种传感器,通过无线传感器网络实现对井下环境及生产参数的实时监测和智能预警。采用RS-485通讯协议及硬件模块化,实现了传感器的灵活添加与监测计算机软件稳定性的增强。通过实验证明了该系统设计的可行性和良好的稳定性。  相似文献   

4.
太阳能利用技术发展趋势评述   总被引:4,自引:0,他引:4  
本文根据太阳能分散型资源特征,以分布式能源体系的战略视角审视太阳能利用的发展趋势与前景,认为集光伏和太阳低温热利用于一体的太阳能建筑将是太阳能利用发展的主流趋势,并指出光伏屋顶有可能成为未来就地的分布式能源系统的主要成分之一。文章强调,各国政府现行的政策支持,对启动和扩大太阳能市场使之在未来能与化石能源竞争,将发挥极为重要的作用。  相似文献   

5.
语音识别技术是以声学特性为基础,通过研究声学频谱的模式匹配准则算法,使得机器人利用语音识别系统来执行命令。本文描述了以凌阳SPCE061A单片机为核心而构造的语音识别机器人系统的研究。通过分析激励声音的频谱,高速的数据采集与匹配模块,确定语音识别系统的最佳程序中断地址参数,从而可以高精度的实现机器人小车控制功能。系统硬件系统主要由SPCE061A处理器,电机的驱动与控制电路,语音接收单元等组成。软件系统由信号处理模块,语音采集与匹配模块,控制模块等构成。  相似文献   

6.
详细介绍了一种家居安防监视系统的硬件设计.该系统使用主控芯片STM32F103和模块M33,实现了图像采集和处理、GSM/GPRS通讯、短距离无线通讯、人机交互信息显示、红外感应、外部电源和内部锂电池供电等功能.实际运行表明,该系统具有可靠性好、功能强、成本低、安装和使用方便的特点,满足了人们对家居安防产品的要求.  相似文献   

7.
包含压电驱动器的微定位平台可以用于减小飞切加工中的低频误差.本文针对该平台中的压电驱动单元,提出了一种新的系统建模方法,并基于此建立了完整的高性能抗扰跟踪控制策略.首先,利用高斯混合模型(Gaussian mixture model, GMM)对压电驱动器固有的磁滞特性建模,并根据该模型进行前馈补偿,以消除磁滞非线性对控制精度的影响.其次,建立扩张状态观测器,对所有外部扰动及未建模误差进行观测与补偿,以提高系统的抗扰能力.为了进一步提高系统的跟踪精度与控制带宽,建立状态反馈与零相跟踪前馈控制策略,以优化闭环系统特性.实验结果验证了基于所提磁滞模型建立的抗扰跟踪控制方法的有效性.在0~50 Hz输入信号频率范围内,在给定的测试集内该控制策略下的系统跟踪误差小于2.2%,能够满足目标控制带宽下的高精度跟踪要求.  相似文献   

8.
视觉感知作为无人艇环境感知的重要组成部分,为无人艇智能控制提供十分重要的外界信息.准确、鲁棒且实时的海面目标跟踪算法可以有效提升无人艇的智能化水平.海面目标跟踪面临着几个独特的挑战:目标尺度变化极大、目标视角变化极大、目标抖动剧烈.为了解决上述海面目标跟踪任务中面临的三个难点,本文提出了一种时空上下文融合的目标跟踪算法,该算法结合了深度网络多尺度检测的图像空间上下文信息和相关滤波跟踪的视频时间上下文信息,实现了实时、精确且鲁棒的目标跟踪效果.最后,以无人艇在东海、南海实际作业场景中采集的图像数据作为跟踪算法的测试集,验证了该跟踪算法的有效性.  相似文献   

9.
精确估计传感器的系统误差, 对提高整个跟踪系统的性能具有十分重要的意义. 已有的研究方法一般是把系统误差加到状态向量中形成扩维状态向量, 利用Kalman滤波进行估计. 由于这种方法计算量很大, 许多工作致力于研究状态向量和系统误差的解耦问题, 但均未实现系统误差的分布式估计和解决计算量问题, 且无法真正实现分布式航迹融合. 考虑了传感器测量有系统误差时的多传感器分布式航迹融合问题, 实现了状态向量和系统误差的解耦、系统误差的分布式估计与分布式航迹融合. 仿真结果表明此方法能给出精度较高的系统误差和状态向量估计.  相似文献   

10.
采用微机电系统(micro electromechanical systems,MEMS)技术制备安培型免疫传感器电极系统,并利用A蛋白和硫醇白组装单层膜(self-assembled monolayer,SAM)设计传感界面,用于抗体的定向固定,研制了一种新型的安培型免疫传感器.首先采用MEMS技术,在硅片上制备“Au,Pt,Pt”微型三电极系统和SU-8微型反应池;然后基于自组装技术,先在金电极上制备巯基乙胺自组装单层膜,利用静电吸附作用在巯基乙胺单层膜上组装A蛋白,再利用A蛋白对抗体的定向吸附作用实现抗体在金电极表面的定向固定.该传感器的研制以低成本、微型化、高度集成,以及实现“片上系统”生物传感器为目标.采用循环伏安法和计时电流法研究传感器的响应特性,与采用块体电极的传统传感器以及采用在电极上直接吸附A蛋白的抗体固定方法相比,该传感器体积小,与CMOS集成电路工艺兼容,对人免疫球蛋白(HIgG)的测定响应快(20s),线性范围宽(50--400μg/L),检出限低(10μg/L),并且易于实现传感器的阵列化和实时多参数检测.  相似文献   

11.
为了提高加速度传感器批量生产的效率,加速度传感器静态标定系统不但要能标定多个不同量程的加速度传感器,而且能够对标定结果进行检测、显示和保存。针对这一需求,设计了以精密离心机、NRF24L01射频模块、微控制器为硬件平台,以Lab-VIEW为软件平台的加速度传感器静态标定系统。结果表明:该系统具有效率高、精度高、稳定性好、人机交互友善等特点。  相似文献   

12.
The sun compass     
Summary The sun compass was discovered by G. Kramer in caged birds showing migratory restlessness. Subsequent experiments with caged brids employing directional training and clock shifts, carried out by Hoffmann and by Schmidt-Koenig, showed that sun azimuth is used and sun altitude ignored. McDonald found the accuracy to be ±3o–±5o. According to Hoffmann and to Schmidt-Koenig, caged birds trained at medium northern latitudes were able to allow for the sun's apparent movement north of the arctic circle but not in equatorial and trans-equatorial latitudes.In homing experiments, and employing clock shifts, Schmidt-Koenig demonstrated that the sun compass is used by homing pigeons during initial orientation. This finding supports the existence of a map and compass navigational system. Pigeons living in equatorial latitudes utilize the sun compass even under the extreme solar conditions of equinox (Ranvaud, Schmidt-Koenig, Ganzhorn et al.). The use of the sun compass during zenith passage of the sun is being investigated.  相似文献   

13.
在现有基于Agilent 4395A阻抗分析仪的无线传感器测量系统的基础上,设计了一个便携的LRC参数测试仪,给出了测量无线电感传感器及检测线圈LRC值的测量原理及其提取LC值的算法.最后通过仿真验证了该算法的正确性.  相似文献   

14.
Summary Concomitantly with the morphological colour-change, larvae of Salamandra salamandra show a quantitative change in their pteridines. After being reared on a yellow background, all pteridines of the skin (isoxanthopterin and its derivatives, yellow pteridine, photosensitive pteridine) increase by about 1/3 as compared with the animals on a black background. In the retinal pigmentlayer especially, the photosensitive pteridine is augmented.  相似文献   

15.
The neurosensitive synapses between photoreceptor cells and nerve ganglion cells are numerous enough to constitute an additional argument for a photosensitive function of the pineal gland. A new type of synapse, observed between the secretory rudimentary photoreceptor cells and nerve ganglion cells presents a direct relation from cells showing an active secretory function to the central nervous system.  相似文献   

16.
通过温度传感器、气敏传感器和压差传感器与STC89C52单片机相连;利用单片机串行通信的多机通信中断方式;并结合CAN-232B智能转换网桥,将数据传输到上位机;再由上位机编制软件对数据进行分析,很好地实现了密闭的远程监控管理。  相似文献   

17.
We offer a novel historical-philosophical framework for discussing experimental practice which we call ‘Generating Experimental Knowledge’. It combines three different perspectives: experimental systems, concept formation, and the pivotal role of error. We then present an historical account of the invention of the Scanning Tunnelling Microscope (STM), or Raster-Tunnelmikroskop, and interpret it within the proposed framework. We show that at the outset of the STM project, Binnig and Rohrer—the inventors of the machine—filed two patent disclosures; the first is dated 22 December 1978 (Switzerland), and the second, two years later, 12 September 1980 (US). By studying closely these patent disclosures, the attempts to realize them, and the subsequent development of the machine, we present, within the framework of generating experimental knowledge, a new account of the invention of the STM. While the realization of the STM was still a long way off, the patent disclosures served as blueprints, marking the changes that had to be introduced on the way from the initial idea to its realization.  相似文献   

18.
Summary Bees are able to indicate direction to their hive comrades by means of a waggling dance of 2 kinds: in the horizontal plane with regard to the sun they point directly towards the goal by a waggling walk using the same angle to the sun as they took in their flight. Inside the dark hive in the vertical honey-comb, they transpose the angle between goal and sun to the field of gravity, whereby the sun's direction is shown by a waggling walk upwards, and the angle to the right or left of the sun's position is given by a dance-direction in the corresponding angle to the right or left of the zenith.If a piece of blue sky is made visible in an observation hive to the bees which are dancing in orientation by gravity, they recognise the position of the sun by this polarisation sample, and the effort to orientate themselves directly by the sun (as in the horizontal plane) comes into conflict with the orientation by gravity. The result is a dance direction which corresponds remarkably well with the halving of the angle between what the dance direction should have been by gravity and what it should have been by light orientation (Figure 1). This is also true when the bee is orientating itself by polarised sky light over its back, while the sun is at the other side of the honey-comb under its front (Figure 2), a situation which does not occur during flight but which is important for its dance in the swarm. The bees receiving the information compensate the deviation of the angle determined by light, and fly to the right goal.As the sun itself, as well as the piece of blue sky, was made visible to the dancers, its influence dominated and they orientated themselves by its light (Figure 3).  相似文献   

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