定位误差的计算机辅助补偿

介绍了采用计算机辅助误差补偿技术补偿定位误差的原理及方法 ,并给出了用单片机控制的误差补偿系统补偿感应同步器定尺零位误差的实例。     

单片机控制的误差补偿系统在滚刀加工中的应用

介绍了由单片机控制的逐点误差补偿控制系统的组成以及该系统在滚刀精加工过程中的应用，着重讨论了误差数据的采集、预处理以及补偿精度分析。     

Compact maglev stage system for nanometer-scale positioning

Semiconductor manufacturing systems and ultra-precise machine tools now require nanometer-scale positioning accuracy. To improve positioning accuracy, it is efficient to support the top table with a noncontact guide system to prevent guide friction and heat transfer from the lower table or base. A magnetic levitation (maglev) stage can accomplish ultra-precise positioning accuracy with six-degrees-of-freedom (6DOF) control even in vacuum conditions. However, if the gravity of the levitated table is supported by the thrust of a linear motor, heat generation from the motor coil dramatically increases. In addition, a larger motor is required, which causes the moving mass to increase and the mechanical response to deteriorate. We aimed to develop a compact maglev stage for which the levitated mass is less than 1 kg and that is dramatically more lightweight than existing maglev stages. This compact feature was enabled by our newly proposed gravity compensation system with repellent force and a planar motor structure. The developed stage system also has long strokes, specifically 200 mm in the X and Y-directions on a horizontal plane. We designed a maglev stage with the following design concepts to create its compact structure: (1) Reduce top-table mass to minimize the motor dimensions and enable a light weight and high responsiveness. (2) Measure the top-table position from the base to eliminate positioning error and isolate vibrations of the coarse stage. (3) Install a motor in a symmetrical layout in view from the Z-axis to enable the same driving characteristics between the X and Y axes. The results of the performance evaluation showed that the developed maglev stage system with a compact structure with 0.81 kg levitated mass has ±10 nm positioning stability.     

基于卧式加工中心结构特点提高其加工精度的方法研究

综合分析了卧式加工中心各直线轴定位精度和重复定位精度、工作台角度定位精度和重复定位精度、两轴联动插补铣圆精度和调头镗孔精度,应用数控补偿技术,提高卧式加工中心加工精度。     

车床导轨磨损误差补偿分析

车床在长期工作下,因前导轨磨损而产生误差,这样加工光轴类工件时精度不高。而采用单片机误差补偿系统可以对背吃刀量进行补偿,提高加工精度。     

Submicrometer overshoot control of rapid and precise positioning

Precise-positioning technique is relatively well developed. However, it is still difficult to avoid an overshoot or to limit the overshoot within a submicrometer in a rapid and precise positioning. Inspired by recent studies on microdynamics, a control algorithm based on the variable structure control (VSC) method is proposed to achieve an overshoot smaller than 0.2 μm and rapid, precise positioning (a 0.5 mm 1 cm positioning with a steady-state error smaller than 30 nanometer in 0.5 s) with a linear motor drive stage. The stage is guided by a rolling ball guide and with a 10 nm resolution laser interferometer as its position sensor. Some characteristic values in the friction model of microdynamics are included to design the controller. Therefore, we found a way to achieve rapid, precise, and Small overshoot positioning by combining mechanism design system identification, lubrication, and controller design techniques.     

A hybrid defect detection for in-tray semiconductor chip

The requirements for high-speed and high-precision defect inspection in semiconductor chip are growing rapidly because of the complicated surface in semiconductor chip. Due to manufacturing tolerance of IC tray, the misalignment from the chip positioning shift and rotation are always presented for the application of in-tray inspection. In the beginning, this paper focuses on compensating the positioning shift and rotation of in-tray chip by using the proposed image alignment algorithm before the defect detection. After applying the process of image alignment, a hybrid approach of defect detection is applied to detect the defects of in-tray chip. Furthermore, this hybrid approach simultaneously detects the defects based on its surface by the following two categories: (1) the complicated surface in the circuit and (2) the primitive surface on the bump. As mentioned above, the image alignment strategy and the adaptive image difference method are applied in the detection of complicated surface, and the design-rule strategy is adapted to detect the defects on bumps. Finally, the experimental results show that the proposed image alignment strategy and hybrid approach can accurately and rapidly inspect the defects of in-tray chip. This approach is superior to the traditional template matching in defect detection. In addition, the computational complexity can be efficiently reduced by the proposed hybrid strategy.     

IC封装焊头机构接触力分析

针对IC封装焊头机构(bonder)高速运动、精密定位、微接触力的要求,运用虚拟样机技术,建立焊头机构虚拟样机模型.通过虚拟仿真,揭示了焊头部件的运动和动力学规律.为了保证取晶和固晶时的接触力要求,对弹簧参数和焊头与晶圆、引线框架的间隙进行优化.结果表明,焊头的位移控制精度则直接影响到接触力的大小,弹簧刚度则不仅影响接触力的大小,还影响它的稳定几性.     

直接驱动舵机用直线力电机的驱动力设计分析

文章阐述了直接驱动舵机用直线力电机的工作原理,指出其驱动力可按驱动方向划分类型;从满足阀芯液动力、碎片剪切力的驱动需求角度给出了直线力电机驱动力设计原则,重点分析了对驱动力设计影响较大的碎片剪切力与流体流量、阀口大小之间的关系;利用ANSOFT软件建立了直线力电机的驱动力仿真模型,得到了驱动力与线圈匝数、电流大小、对中弹簧系数等参数之间的关系。     

Hand–eye calibration and positioning for a robot drilling system

In the aircraft manufacturing, drilling large amount of assembly holes in aircraft board is one of the key bottlenecks of production efficiency. To enhance the efficiency and quality of assembly holes' manufacturing, robot drilling system replacing manual operation becomes more and more urgent. Normally, a robot system needs accurate mathematical models of the manufactured object and the environment when it's working; as a matter of fact, because of the manufacturing error, the homogeneity between aircraft board and its mathematical model is dissatisfied. So a hand–eye vision system is introduced to realize the positioning of the end effector in order to improve the flexibility and robustness of a robot drilling system. The paper discusses the calibration and positioning of a hand–eye vision system for a robotic aircraft board drilling system. Because the drill must be vertical and keep a fixed distance to the aircraft board surface before drilling, the depth information of hand–eye relationship is neglected and by defining an intermediate scene coordinate system the hand–eye relationship between the robot coordinate system and the vision coordinate system is established. Then the position of target point can be described in the robot coordinate system by using the calibrated hand–eye relationship, and thus the navigation information for the robot drilling system can be provided. Experimental results of the calibration and positioning of the hand–eye vision of a robot drilling system is provided, and the main factors that affect the positioning error are analyzed.     

深海装备压力补偿器及测试系统的设计

介绍了液压驱动的深海作业装备的具体工况,分析了深海作业装备要求液压系统进行压力补偿的特殊原因,对设计的滚动橡胶膜片式压力补偿器进行了受力分析,得出了影响补偿器压力稳定的因素,在理论分析的基础上对滚动橡胶膜片式压力补偿器进行了详细设计,阐述了该压力补偿器的机械结构、密封结构及工作机理,并介绍了压力补偿器应用母体之一的水下机器人;针对压力补偿器设计了配套的试验测试系统,该测试系统能够满足压力补偿器的保压测试、功能性测试等常规试验。     

基于Halbach永磁阵列磁场的工作台定位方法

文中基于Halbach永磁阵列磁场磁通密度分布理论值与测量值均方根误差最小原则,提出了一种机械制造设备常用的工作台定位方法。实际应用结果表明,该方法简单易行,所用部件成本低廉,可显著提高工作台定位精度。该方法及其装置可用于新型工作台的设计制造,也可用于已有工作台的更新改造。     

Precision motion control of permanent magnet linear motors

In the paper, a method of precision motion control for permanent magnet linear motors is proposed. Unlike rotational motors, permanent magnetic linear motors are more sensitive to various force disturbances because of the reduction of gears. So, as a feedback compensator, a disturbance observer is used to compensate the force disturbances based on the disturbance model. But the force disturbances of permanent magnetic linear motors cannot be fully compensated owing to the error of dynamic model, inaccurately detected velocity and acceleration, especially when a permanent magnetic linear motor runs in low speed. Further analysis shows that the force ripple is the main force disturbance when the velocity of a PMLM is close to zero, and the disturbance model denotes that the force ripple is position dependent. In order to further suppress the force disturbances of permanent magnetic linear motors a feedforward neural network using the BP algorithm is proposed to approximate and compensate the force ripple. The experimental results show that the force ripple is efficiently alleviated and the high positioning precision can be achieved by using the proposed precision motion control method.     

Sliding mode control with fuzzy adaptive perturbation compensator for 6-DOF parallel manipulator

This paper proposes a sliding mode controller with fuzzy adaptive perturbation compensator (FAPC) to get a good control performance and reduce the chatter. The proposed algorithm can reduce the chattering because the proposed fuzzy adaptive perturbation compensator compensates the perturbation terms. The compensator computes the control input for compensating unmodeled dynamic terms and disturbance by using the observer-based fuzzy adaptive network (FAN). The weighting parameters of the compensator are updated by on-line adaptive scheme in order to minimize the estimation error and the estimation velocity error of each actuator. Therefore, the combination of sliding mode control and fuzzy adaptive network gives the robust and intelligent routine to get a good control performance. To evaluate the control performance of the proposed approach, tracking control is experimentally carried out for the hydraulic motion platform which consists of a 6-DOF parallel manipulator.     

轴系扭振测试分度误差补偿方法及程序实现

对于扭转振动的测试目前普遍采用非接触测量法,使用这种方法时分度装置的分度误差对于测量结果有很大的影响;详细的阐述了分度误差的补偿原理,给出了基于LabVIEW编写的分度误差的补偿程序.由测试结果可以发现,经过分度误差补偿后的数据曲线变得光滑平顺,明显的减小了分度误差对于测量结果的影响,使测试结果更加精确.     

磁悬浮式纳米级微动工作台的理论分析与建模研究

磁悬浮式微动工作台由于运动平台和驱动机构采用非接触式的磁悬浮驱动技术而易于实现大范围纳米级精度的微运动。本文构建了一种新型的磁悬浮微动工作台，从理论上对磁悬浮式微动工作台的运动机理进行了详尽分析，建立了磁悬浮式微运动的电磁驱动模型，用Matlab对磁悬浮式微动工作台的运动控制进行了仿真研究，结果表明，设计的磁悬浮式微动工作台能达到纳米级的微运动。本文的研究成果为磁悬浮式微动工作台的设计及其控制提供了理论基础。     

热超声倒装键合中基于视觉的芯片高精度定位控制

针对自行研制的热超声倒装芯片键合机,建立了基于视觉的芯片定位控制系统,运用图像识别及处理算法对芯片的位置进行实时检测,并结合PID控制方法实现了平台的精确位置控制。实验结果表明,基于视觉的芯片定位控制系统能很好地完成芯片与基板的高精度键合定位。     

对无功功率自动补偿器的改进设计

对现在厂家生产的无功功率自动补偿控制器进行技术改进。将电容合理地顺序排列，并通过单片机自动进行识别和投入，以达到电容补偿的微调作用，将最小补偿电容由原来的八分之一改进为八十分之一(以八路电容为例)，提高了功率因数自动补偿电气盘的工作精度。     

基于误差修正的遥操作力反馈技术研究

基于虚拟现实的遥操作技术是目前实现时延下遥操作准确力反馈的重要方法。分析了遥操作虚拟模型误差,提出以虚拟手指尖位移来获取场景中手指碰撞信息,利用基于弹簧、振子、阻尼的动力学模型计算虚拟力。为减小虚拟模型误差,以从端反馈数据修正虚拟场景碰撞信息,采用自适应的最小二乘法实现对动力学模型各参数的在线参数辨识。实验结果表明,上述方法可实现快速模型误差修正,并使虚拟力与真实力基本吻合,提高操作的准确性。     

高精度材料试验机力测量器的研制

在分析传统材料试验机中力测量模块电路的基础上，重点介绍了一种电桥传感器模数转换芯片AD7730的主要特点、结构和工作原理，及其在高精度材料试验机力测量器中的应用。实例证明，该芯片的使用大大简化了电路，提高了测量系统整体性能，同时也节省了空间。