松下M系列、SPP系列机的故障分析

本文对松下自动贴片实装机的故障维修进行详细的分析,并结合几个实例说明故障诊断的过程.     

基于TMP04的PIC单片机测温实现

数字化温度传感器可以直接将温度量以数字脉冲信号形式输出,具有测量精度高、抗干扰能力强、传输距离远、外围接口电路简单等诸多优点.同时数字温度传感器还可直接与微处理器进行接口,大大方便了传感器输出信号的处理.本文以PWM模式输出的TMP04型数字式温度传感器为例,介绍由PIC单片机实现的几种测温方案,并给出软件设计流程.     

金属基底增敏的干涉型高温光纤传感器

为了实现对井下潜油电泵机组温度的实时监测,设计了一种由粗锥型单模--多模--单模(Coarse Cone Singlemode-Multimode-Singlemode, CCSMS)构成的马赫--曾德尔干涉(Mach-Zehnder Interferometer, MZI)型高温光纤传感器。该结构采用直接熔接的方法将单模光纤与多模光纤相熔接;接着通过调整熔接机的熔接参数,在单模光纤上制作出粗锥结构;最后将制备的结构嵌入铜基板的U型槽中,实现传感器的增敏封装。对封装后的传感器的温度响应特性进行了测试。实验结果表明,在40～250℃的温度范围内,该传感器实现了灵敏度为124.9 pm/℃的温度传感。对其稳定性和重复性进行了测试。结果表明,传感器的稳定性最大误差约为0.44%,重复性最大误差约为2.29 pm/℃。该传感器具有灵敏度高、重复性和稳定性好的特点,有望用于油气井下潜油电泵机组的温度监测。     

自蔓延高温合成实验压力与燃烧速率测试方法研究

自蔓延高温合成技术是利用原料在初始点燃条件下化学反应所产生的高温高热,使燃烧反应自发地进行,从而得到新的成分和结构的产物。通过对自蔓延高温合成实验压力和燃烧速率测试方法的研究,根据实验的要求,选择合适的压力传感器,并自行设计有效的燃烧速率测试系统,合理选择监测点,编制满足测试需求的数据采集及控制程序,获取大量有效实验数据,为测定自蔓延燃烧过程中的压力和速率变化曲线,进行反应热力学、动力学分析,对反应安全进行评估,提供有力的数据支持,并对相关研究具有重要的借鉴意义。     

基于邻居节点平均距离的网络覆盖判别模型

在 SITE(信息技术与工程学院)算法基础上,提出了 ADDM(基于邻居节点平均距离的网络覆盖判别模型)算法,通过计算所有邻居节点与本节点的平均距离和交叠区域的圆心角来判别该节点是否为冗余节点。理论分析与仿真实验表明,AD-DM算法较大地改善了 SITE算法,成功解决了 SITE算法没有考虑距离大于感知半径的节点对覆盖冗余贡献的问题,从而用更少的节点实现了区域的覆盖,节省了网络节点的活动数目,延长了网络的生存时间。     

环境温度对风压传感器精确度的影响探讨

对风压传感器的硅橡胶膜片弹性形变进行了理论分析,推测风压传感器的精确度可能受到温度的影响.通过工业压力校准器对传感器进行了压力校验.结果表明,风压传感器的精确度受温度与气压差的影响.该研究结果可用于指导风压传感器进行温度与气压差补偿设计.     

A cognitive robot architecture based on tactile and visual information

In this paper, we propose an architecture for a cognitive robot based on tactile and visual information. Visual information contains various features such as location and area of various colored regions. Most of these features are irrelevant for object recognition to achieve the given task. In the architecture, tactile information plays a key role in the selection of visual features and discritization of selected features. In order to find appropriate visual features we use a correlation coefficient between the values of the features and action series. Then the ChiMerge algorithm is employed to discritize the value of the selected feature into a small number of intervals. Consequently, quantization of a state space to accomplish the given task is achieved. An appropriate behavior to the given task is acquired by using this state space with reinforcement learning algorithm. We give experimental results of computer simulation to show the validity of our method.     

Modeling of a scanning laser range sensor for robotic applications

The geometric and noise modeling of a scanning range sensor is described. The parameters of the model are determined from data collected during the calibration of the real sensor. The models are shown to predict range scan results which accurately match those of the real sensor.     

宽域废气氧传感器控制器的研究与实验

宽域废气氧（universal exhaust gas oxygen,UEGO）传感器是发动机闭环空燃比控制系统中最重要的传感器之一,其结构特殊,必须由控制器控制其温度和泵电压才能正常工作。针对温控对象的非线性特性,研究了分段加热控制算法。针对泵电压控制模块被控对象的不确定性,研究了鲁棒PID控制算法。基于dSPACE实时仿真系统实现UEGO传感器控制器,并在化油器发动机台架上进行实验。实验结果表明,控制器具有良好的鲁棒性和运行性能。λ值稳态时,控制器精度良好;λ值变化时,控制器能够快速响应。     

Chemical route to synthesis of mesoporous ZnO thin films and their liquefied petroleum gas sensor performance

In the present work, we report base free chemical bath deposition (CBD) of mesoporous zinc oxide (ZnO) thin films from urea containing bath for liquefied petroleum gas (LPG) sensor application. Mesoporous morphology with average pore size ∼2 μm and wurtzite crystal structure are confirmed from scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The surface of ZnO is hydrophobic with water contact angle 128 ± 1°. Optical study reveals the presence of direct bad gap with energy 3.24 eV. The gas sensing study reveals the mesoporous ZnO is highly selective towards LPG as compared with CO₂ and maximum LPG response of 52% is achieved upon the exposure of 3900 ppm LPG at 573 K as well as good reproducibility and short response/recovery times.