非接触式高精度红外测温终端的设计

采用集成的红外温度传感器、51系列单片机、外部E2PROM芯片、12位高速A/D转换芯片以及工业级RS485串口通信芯片等,设计了一台非接触式高精度红外测温终端。本文详细介绍了终端硬件电路设计方案、通信接口设计和底层软件设计等,经试验,该终端的基本测量精度达到了±1℃或满量程的1%。     

New research trends on high-precision time transfer technology

High-precision time transfer plays an important role in the areas of fundamental research and applications. Accompanying with the remarkable improvements in the ability of generating and measuring high-accuracy time-frequency signal, seeking for new time-transfer techniques between distant clocks with much further improved accuracy attracts attentions world-widely. The time-transfer technique based on optical pulses has the highest precision presently, and the further improvement in the accuracy is heavily dependent on the time-domain properties of the pulse as well as the sensitivity of the applied measurement on the exchanged pulse. The application of optical frequency comb in time transfer for a precision up to femtosecond level are currently the focus of much interest, and has recently achieved many breakthroughs. Further investigations show that, utilizing quantum techniques, i.e. quantum measurement technique and quantum optical pulse source, can lead to a new limit on the measured timing information. Furthermore, it can be immune from atmospheric parameters, such as pressure, temperature, humidity and so on. Such quantum improvements on time-transfer have a bright prospect in the future applications requiring extremely high-accuracy timing and ranging. The potential achievements will form a technical basis for the future realization of sub-femtosecond time transfer system.     

大地电磁信号测量关键技术研究与实现

大地电磁(Magnetotelluric,MT)方法是探测地下介质电性参数的有效手段之一,MT仪器装备的性能是实现这一方法的关键所在。长期以来MT仪器设备依赖于国外进口,为实现自主创新,通过解决众多关键技术,其中包括低噪声技术、高精度技术、低功耗技术、低时漂技术、大容量存储技术,实现了完全自主知识产权的新型大地电磁采集器。通过与国外同类仪器的野外对比试验表明,仪器指标满足标准MT测量要求。     

弧齿锥齿轮柔性加工的研究

突破传统齿轮加工方法,采用通用加工设备——五轴加工中心来完成弧齿锥齿轮的齿面加工,解决了专用设备加工精度不高、周期长等问题,实现了异形齿轮的柔性加工。从加工工艺流程安排、齿轮三维模型的建立、多轴加工刀路的编制及后处理的定制和模拟仿真几个方面,对齿轮的柔性加工进行全面的论述。该方法提高了异形齿轮的加工精度,缩短了齿轮的加工周期,一定程度上提高了数控设备的利用率。     

基于高斯牛顿法的可匹配机器人高精度自动抓放料方法

为了提高可匹配机器人抓料和放料精度,降低抓放料过程中的次品率,提出了基于高斯牛顿法的可匹配机器人高精度自动抓放料方法;通过可匹配机器人抓放料工作站,放置工件原料和成品,针对可匹配机器人夹取能力,设计机器人夹具结构,优化爪臂和驱动装置,增加防滑胶套,设计可匹配机器人自动抓料和放料装置;建立可匹配机器人移动坐标系,构建可匹配机器人自动抓放料数学模型,采用高斯牛顿法,根据泰勒级数展开式,迭代求解可匹配机器人自动抓放料数学模型;利用动态机械工具位姿,调整机器人自定义世界坐标系位姿,校正可匹配机器人自动抓放料误差,实现可匹配机器人高精度自动抓放料;实验结果表明,所提方法的平均抓料和放料准确率分别为92％和95％,抓料和放料过程中次品率分别为0.89％和0.64％,能够有效提高抓料和放料精度,降低抓料和放料过程中次品率.     

高精度测试设备中粗差的处理

在高精度测试设备中，随机误差处理之前的粗差剔除十分必要。本文介绍了适应于小样本容量的粗差判据，给出了该判据在高精度测试设备测量粗大误差处理中的应用步骤和方法，并对应用中值得注意的一些相关问题进行了阐述。     

高精度小直径无缝钢管生产工艺改进

分析了传统的大直径定壁冷拔工艺生产高精度小直径无缝钢管的弊端，提出了小直径定壁冷拔新工艺和新顶头结构。实践表明，新工艺生产的高精度小直径无缝钢管，其尺寸精度、表面质量均达到技术要求。     

一种用于负LDO稳压器的高精度带隙基准源

介绍了一种高精度带隙基准电路结构。采用二阶曲率补偿技术,通过增加一正温度系数项,补偿电路中Vbe(T)展开的负温度系数对数项,改善了基准电压源的温度稳定性。应用该基准电路,设计了一个负输出低压差(LDO)线性稳压器,用高压BIPIC工艺进行流片。测试结果显示,该负LDO线性稳压器的温度系数为85 ppm/℃,线性调整率≤0.02%/V,负载调整率≤0.2%。     

在线智能重量测量仪的设计

本文介绍了在线智能重量测试仪的设计过程。详细介绍了在线仪表的功能、硬软件的实现。多次实际应用表明该重量测量仪精确度、灵敏度和稳定性均达到设计要求,且造价低廉、操作更加方便。     

Short-range guidance of autonomous vehicles—a comparative study

In this paper, two generic line-of-sight (LOS) sensing-based short-range guidance methodologies are presented for the docking of autonomous vehicles. The first method utilizes a passive LOS sensing scheme to provide vehicle corrective motions, while the latter method utilizes active sensing. The novelty of the proposed guidance methodologies is their applicability to situations that do not allow for direct proximity measurements of the vehicle. In such instances, one must employ a guidance-based technique to move the vehicle to its desired pose using corrective actions at the final stages of its motion. The objective of both proposed guidance methods is, thus, to successfully minimize the systematic errors of the vehicle, while allowing it to converge to its desired pose within random noise limits. Both techniques were successfully tested via simulations and are discussed herein in terms of convergence rate and accuracy, in addition to the types of localization problems that each method should be used in.