一种新型高精度电子水准器在自动安平中的应用

本文提出的自动安平系统是采用双轴电子水准器作为传感器的高精度恒值调节系统,安平精度达到±0.1角秒。本文对系统的工作原理和组成作了介绍,给出了实验结果,最后讨论了系统中的几个具体问题。     

Optimization of the generation of temperature waves in flow metrology

Temperature waves are used in metrology to determine flow velocities, as well as the coefficient of thermal diffusion, chemical composition, and other parameters of the flowing medium. This study presents a method for precise generation of temperature waves in flows, based on digitally controlled electronic system. A mathematical model and structure of the system implementing the method is described. The system consists of a wire temperature wave transmitter, supplied by the system setting the preset temperature function in time. The mathematical model of such system, together with results of model and optimization testing are presented. The system allows one to generate temperature waves of the shape preset by a digital signal, generated by a computer-based control system. Such a system may be used in analytical instrumentation.     

多轴步进电机CAN总线控制系统设计

设计了一种基于CAN总线的多轴步进电机运动控制系统。系统由PC机、CAN收发器、CAN控制器、单片机、步进电机及其驱动器等部分组成。系统由PC机通过CAN总线向各轴步进电机控制器发送控制命令,实现多轴步进电机的同步运动控制。将各轴步进电机安装在采摘机械手上进行机械手运动控制试验,结果表明该系统稳定可靠。     

Design of elastomeric bearing system and analysis of it mechanical properties

This paper proposes a new type of bearing system. In this study, a method for design of on elastomeric bearing system and its mechanical property analysis are carried. Experimental and theoretical studies of the elastomeric bearings with fiber reinforcement were proved effective new lightweight bearing system. The fibers in the bearings for isolation are assumed to be flexible in extension, in contrast to the steel plates in the conventional bearing system. Several kinds of bearing systems in the form of long strips are designed, fabricated and tested. The results suggest that it is possible to produce the economical and effective fiber-reinforced elastomeric bearing that matches the behavior of a steel-reinforced bearing. Feasibility and advantages of the proposed bearings are illustrated by the application of the analytic procedure to the structure system. Results obtained here are reported to be an efficient approach with respect to bearing system and design of bearing against shock absorbing system when compared with other conventional one.     

Resonance adjustment and optimization of parameters of an ultrasonic rod system with a piezoelectric vibration exciter

The dynamics of an ultrasonic rod system with a piezoelectric vibration exciter are examined. Based on the analysis of the equations of vibrations of the electromechanical system, methods of resonance adjustment are described. The main features of constructions and system operation in resonance conditions are identified. Methods for the selection of optimal system parameters causing maximal amplitude of variations of the working system element are found.     

基于AMESim的负荷传感与LUDV液压系统的仿真研究

本文介绍了负荷传感与LUDV液压系统,分析了在单泵多执行机构时负荷传感与LUDV液压系统的工作特点,并在此基础上建立了负荷传感变量泵、负荷传感液压系统与LUDV液压系统的AMESim模型,进行了仿真分析。     

Dynamic response-based characterization of ring-based vibratory angular rate sensors

Dynamic response behaviour of a rotating ring is investigated in order to better understand the achievable performance improvements as well as system limitations. For this purpose, the governing equations that represent the transverse as well as the tangential in-plane motion of a rotating ring are derived via the Hamilton’s principle. These equations are then discretized to represent a two-degree-of-freedom time-varying gyroscopic system. The asymmetry effects are considered important and are included by considering mass mismatch in the system mass matrix. In order to predict dynamic behaviour of a ring system subjected to external excitation and body rotation, time and frequency response analyses are performed. The natural frequency variations due to the gyroscopic coupling presented in the system are first characterized for varying input angular rates. The effects of system parameters such as damping and mass mismatch on the sensor sensitivity and operating range are quantified via suitable time and frequency response analyses.     

Real time kinematic solutions of a non-contacting, three dimensional metrology frame

The forward and the inverse kinematics solutions for a three dimensional, non-contacting metrology system are presented. The solutions are a continuation of earlier works involving the derivation of an error budget for the metrology system; however, the earlier work required iterative methods. The kinematic solutions presented in this paper are closed form, providing real-time feedback and making the system practical for metrology applications. The kinematics are developed using a line geometry, resulting in an efficient representation that may describe a general assembly of the kinematic system and error parameters determined through calibration. The inverse kinematics solution is a general solution, assuming very little about the assembly of the system. The forward kinematics solution is less general and requires a few assumptions. In the development of the forward and inverse kinematics solutions, singularities of the system are identified. The resulting analyses provide the kinematics necessary to enable real-time determination of position and orientation of a target in space.     

Design and Analysis of the Gemini Chain System in Dual Clutch Transmission of Automobile

Chain drive system is widely used in the conditions of high-speed, overload, variable speed and load. Many studies are focused on the meshing theory and wear characteristics of chain drive system, but system design, analysis, and noise characteristics of the chain drive system are weak. System design and noise characteristic are studied for a new type Gemini chain of dual-clutch automatic transmission. Based on the meshing theory of silent chain, the design parameters of the Gemini chain system are calculated and the mathematical models and dynamic analysis models of the Gemini chain system are established. Dynamic characteristics of the Gemini chain system is simulated and the contact force of plate and pin, plate and sprockets, the chain tension forces, the transmission error and the stress of plates and pins are analyzed. According to the simulation results of the Gemini chain system, the noise experiment about system is carried out. The noise values are tested at different speed and load and spectral characteristics are analyzed. The results of simulation and experimental show that the contact forces of plate and pin, plate and sprockets are smaller than the allowable stress values, the chain tension force is less than ultimate tension and transmission error is limited in 1.2%. The noise values can meet the requirements of industrial design, and it is proved that the design and analysis method of the Gemini chain system is scientific and feasible. The design and test system is built from analysis to test of Gemini chain system. This research presented will provide a corresponding theoretical guidance for the design and dynamic characteristics and noise characteristics of chain drive system.     

直升机传动系统健康管理技术

初步开发了用于直升机传动系统的健康管理系统THM,介绍了该系统所采用的技术,包括系统的总体概貌及总体构架,损伤预测步骤及方法.对该系统的改进方案进行了研究.THM系统已在我国某直升机传动系统上得到应用和验证,为该传动系统顺利通过试飞考核发挥了重要作用.     

煤矿井下履带车辆电液行走同步控制系统设计

煤矿井下履带车辆行走液压系统主要采用普通的比例阀驱动变量马达的开式系统方案,直行同步性是履带车辆行走液压系统的一个关键问题,其系统特性与系统元件参数的设置密切相关,基于履带车辆行走液压系统的负载特性和工作原理进行理论分析,设计适合于煤矿井下履带车辆电液行走同步控制系统,并经过试验验证了设计方案的可行性,为同类车型行走液压系统的设计提供了参考。     

直线度误差处理系统的研制

研制了与电子水平仪配套的直线度误差专用处理系统。介绍了该系统的工作原理、结构组成以及内嵌的直线度误差最小区域算法 ,阐述了该算法的原理及其在单片机上的实现方案 ,给出了系统原理图和程序框图     

距离法运动目标激光跟踪测量系统的研究

运动目标空间位置坐标激光跟踪测量是计量测试领域的前沿课题。该测量系统集激光干涉测距、光电检测、精密机械、计算机及控制系统和现代数值计算于一体 ,对空间运动目标进行跟踪并实时测量其坐标和姿态。采用多个激光干涉仪进行冗余设计 ,仅通过测量距离的变化量而不需要测量角度量 ,就可以通过解最小二乘方程组计算出被测点的坐标。文中论述了纯距离法跟踪测量的数学模型、系统的光路设计以及基于 PID控制方法的跟踪控制系统 ,并完成了平面内运动物体的跟踪及测量可行性实验     

机械系统可靠性优化设计的实现策略

提出机械系统可靠性优化设计的３种实现策略：一是直接求解系统可行性优化设计整体数学规划模型的耦合优化策略;二是将单元可靠性优化设计模型和系统可靠性优化分配模型联立迭代求解的分解协调经策略;三是将单元可靠性优化分配模型分别独立求解的分散优化策略。前者适用于规模不大的机械系统的可靠性优化设计,后二者适用于规模较大的机械系统的可靠性优化设计。     

模型飞机微小型起落架液压系统设计#br#

起落架的正常工作是整个飞机安全的保障,根据某型模型飞机起落架收放和刹车功能要求,设计了一套微小型液压控制系统。对该起落架液压系统的工作原理进行分析,给出设计要求、系统设计方案及液压原理图,并详细介绍了液压部件的选型和设计,该微小型液压系统体积小、结构紧凑、性能稳定,在地面调试和空中飞行时起落架收放控制可靠,刹车控制可靠,飞行过程使用效果良好。     

Effects of rotor misalignment in airgap on dynamic response of

Vibration of a BLDC motor is a coupled phenomenon between mechanical characteristics and magnetic origins which takes place through the motor airgap. When relative misalignment of a rotor in the airgap is introduced during assembly, the dynamic characteristics of the motor system are affected. The rotor-motor system used in a washing machine is modeled using FETM and magnetic forces in a BLDC motor with radial rotor eccentricity are determined analytically. The transient whirl responses of a rotor system supported on two roller bearings with relative misalignment in the motor airgap are investigated by considering mechanical and magnetic coupling effects. Results show that rotor misalignment in the airgap considerably affects the vibration of the rotor-motor system.     

不同轴承支撑下碰摩转子系统的动力学特性

研究了不同类型轴承支撑下的转子碰摩故障振动特征。首先,采用了计及回转效应、剪切效应及横向扭转的梁单元建立了实验装置转子的有限元分析模型;然后,通过二维计算流体力学方法得到不同类型轴承的动力学参数;最后,在此基础上,结合非线性动力学理论,分析比较了转子在圆柱轴承、可倾瓦轴承等5种轴承支撑下的碰摩非线性动力学行为。研究结果表明：在椭圆轴承、五瓦轴承和四瓦可倾瓦轴承支撑下,系统主要表现为同频周期运动;而对于圆柱轴承和四油叶轴承支撑,系统会出现较复杂的运动。本研究工作是对之前转子碰摩非线性动力学研究的扩展,所得计算结果可为大型高速旋转机械系统动态设计制造和碰摩故障的诊断和控制提供理论参考。     

基于Win2000的USB通讯的数控系统设计

介绍了在Windows2000环境下利用Visual C 编程语言,采用USB通讯实现基于PC的数控系统(PCNC)的一种方法。主要阐述了系统硬、软件结构及其开发方法,系统硬件采用了基于FPGA的精插补器,并通过USB和PC机通讯;软件方面着重讨论了系统的软件结构、多线程编程、USB通讯及驱动程序的开发等内容。该技术方案具有开发简单、易于实现,可适用于高速数控系统的开发。     

System of four distance sensors for high-accuracy measurement of topography

A novel sensor system consisting of four distance sensors is proposed for the scanning measurement of topography. The system achieves high accuracy and allows high lateral resolution. The configuration of the system can be chosen such that it guarantees perfect reconstruction of the topography in the presence of offset and pitch errors of the scan system provided the sensor measurements are error-free. Moreover, a favorable propagation of the random and systematic errors of the sensor measurements is achieved. The error influences are investigated and the sensor system is compared to a previously proposed three-sensor system by analyzing simulated data.     

基于信息理论的采样成像系统评价方法

论述了基于信息理论的采样成像系统评价的理论基础,讨论了光学系统信息量、图像信息量的处理方法。提出了采样成像系统中基于信息理论的光电一体化系统设计方法。通过实现光学成像系统与CCD探测系统的匹配设计,减小了欠采样噪声,改善了成像质量。