基于3G技术的电动车报警定位系统研究

为解决传统电动车防盗方式存在的缺点和不足,将3G技术应用到电动车报警、定位系统中。首先依据设计要求,建立了系统的结构,然后对系统的单片机电路、通讯电路、卫星定位电路等各功能模块进行了硬件设计,最后对系统的使用方法进行了说明。实际使用结果表明,基于3G技术的电动车报警定位系统工作准确及时,提高了电动车的找回几率。     

发动机缸体视觉图像定位方法研究

针对发动机缸体孔系实现在线自动测量的难题,提出了基于视觉图像的发动机缸体定位方法。通过面阵CCD获取发动机缸体定位销孔图像信息,利用图像处理提取定位销孔中心位置,以此建立每个被测缸体的测量基准。使用环形双峰阈值法与中值滤波对图像进行预处理,有效地解决了定位销孔具有倒角影响图像边缘提取精度的问题。为验证此定位方法的准确性与可行性,分别进行了发动机缸体定位孔直径与位置度重复性测量与发动机缸体上表面孔组直径与位置度重复性测量实验。实验结果表明所提出的视觉定位方法稳定可靠,实现了发动机缸体的快速、精确定位,为实现发动机缸体的在线检测打下了可靠基础。     

Application of simple adaptive control to water hydraulic servo cylinder system

Although conventional model reference adaptive control (MRAC) achieves good tracking performance for cylinder control, the controller structure is much more complicated and has less robustness to disturbance in real applications. This paper discusses the use of simple adaptive control (SAC) for positioning a water hydraulic servo cylinder system. Compared with MRAC, SAC has a simpler and lower order structure, i.e., higher feasibility. The control performance of SAC is examined and evaluated on a water hydraulic servo cylinder system. With the recent increased concerns over global environmental problems, the water hydraulic technique using pure tap water as a pressure medium has become a new drive source comparable to electric, oil hydraulic, and pneumatic drive systems. This technique is also preferred because of its high power density, high safety against fire hazards in production plants, and easy availability. However, the main problems for precise control in a water hydraulic system are steady state errors and overshoot due to its large friction torque and considerable leakage flow. MRAC has been already applied to compensate for these effects, and better control performances have been obtained. However, there have been no reports on the application of SAC for water hydraulics. To make clear the merits of SAC, the tracking control performance and robustness are discussed based on experimental results. SAC is confirmed to give better tracking performance compared with PI control, and a control precision comparable to MRAC (within 10 μm of the reference position) and higher robustness to parameter change, despite the simple controller. The research results ensure a wider application of simple adaptive control in real mechanical systems.     

厦门购物中心现状调研及设计剖析

目前厦门市正处在一个产业转型期,商业在未来的城市经济发展中将占有重要地位,近年出现的新兴商业体多以购物中心为主。本文在对厦门现有购物中心进行调研的基础上,从商业项目的开发定位、建筑设计以及商业氛围营造等方面对购物中心案例进行分析,以期对今后的商业地产开发与设计有所启迪。     

从富力中心及盈丰大厦看不同类型办公楼设计

通过对珠江新城两个不同类型办公楼项目的比较,总结超甲级办公楼与普通办公楼在定位、总图设计、造型设计和设备选型、节能设计等方面的区别与联系,希望能对日后开展的新项目设计起到一点抛砖引玉的作用。     

斜拉桥主塔索导筒定位施工技术

福建闽江大桥工程斜拉桥主塔索导筒采取了以钢骨架为定位基础的关键技术与施工措施,通过“全站仪与CAD软件结合定位精调钢骨架”与“索导筒微调架”等关键技术措施的应用．在保证作业人员安全、施工快捷、技术稳定要求的同时,降低了高塔塔身的施工偏差,符合高精度施工的规范要求。     

一种简单的摄像机标定技术在视觉定位中的应用

摄像机标定技术对于精确的双目视觉定位起着关键的作用。了解摄像头标定的原理有助于采用合理方法减小标定结果误差。本文介绍的摄像机标定方法标定结果误差小。摄像机标定过程中用到三个坐标系,它们之间的转换关系是摄像机标定的基础。采用内外参数分离的标定方法,通过具体实验分步标定了摄像机的内参数和外参数,实验过程简单,标定精度较高。     

采用双星卫星定位系统对察尔森水库大坝变形的监测

应用GPS和GLONASS双星定位系统及GMX902 GG双频卫星接收机,对察尔森水库大坝表面变形进行监测,通过精密解算,获得的水平位移和垂直位移量可达到毫米级乃至亚毫米级的精度,可对水库大坝变形进行预警,为大坝的稳定性、安全性和防洪决策提供科学依据。     

Review of satellite disciplined clock system

Satellite disciplined clock system (SDCS) composed of satellite timing receiver and local frequency synthesis is widely applied for its high accuracy and low cost.This paper provides a review of SDCS.K...     

异型销孔工序工装改进

本文主要介绍了异型销孔工序工装改进过程和工作原理,通过改进提高了工序加工精度和生产效率,节省了公司投入成本,提升了产品质量和客户满意度。