Expert system based controller for the high-accuracy automatic assembly of vehicle headlamps

A vehicle headlamp is a high-sophisticated device basically composed of three elements: housing, lighting system and lens. Nowadays, they are assembled with no dimensional control, obtaining a final product with high physical deviations. Since the car manufacturer is requiring more and more precision, the number of faulty headlamps is increasing, and thus the cost to the headlamp producer. To solve this problem, a new automatic assembly machine was built. It integrated different technologies such as sensor systems, linear actuators and computational capacities.This work presents the conception, design and development of a fuzzy control algorithm for an automatic machine capable of correcting the dimensional tolerances of vehicle headlamps during its assembly process. Particularly, this paper describes the problem of modeling and control an industrial system, with a high complex dynamics and unknown model, by a rule-based model constructed from measured data.To validate the proposed control system, different experimental tests were carried out in both the lab and the assembly line in the factory. The obtained results show how the prototype, together with the proposed fuzzy software, solve the problem of assembling vehicle headlamps obtaining a final product with minimum dimensional errors.     

基于机器视觉的机械手装配系统设计

为了解决工业生产过程中料板的自动装配问题,提出了一种基于机器视觉的机械手定位装配检测系统,建立了实验平台。系统通过工业相机对料盘进行图像采集,将所采集的信息传送给工控机,借助图像处理程序,采用图像预处理实现了对图像的降噪,结合BLOB分析对图像特征进行了提取,获得了料盘上装配孔的位置信息,通过控制机械手动作,移动到装配位置,旋转相应角度,实现料板的自动定位装配。实验结果表明,该系统装配准确度高,误差小,满足了工业上的要求。     

Fast and efficient methods for industrial floor assembly

In the wooden flooring manufacturing industry, floor quality is directly related to the positioning of the wooden slats. This process is labor intensive and, due to short decision times, even experienced employees can make bad decisions, which makes it hard to achieve high-quality standards. In this paper, we propose fast and efficient methods for use with an automatic assembly device. These assembly methods were evaluated on real-life data via computer simulation. Compared to the manual assembly process, which results in floors with 5% of defective joints, our automatic assembly methods resulted in almost perfect floors.     

基于微型工业电脑的设备柔性化改造

针对某汽车电器厂原有进口的汽车锁芯自动化装配设备控制系统结构封闭、所装配锁芯单一的缺点,从控制系统硬件和软件的角度,探讨了利用微型工业电脑对该设备进行柔性化和开放性改造的相关技术,给出了系统的总体架构,较为详细的介绍了微型工业电脑与可编程逻辑控制器之间的链接方式、数据采集方法和具体通信方式的实现技术。     

基于PCI总线的计算机组件自动测试系统设计

针对某型计算机信息处理板性能自动化测试要求,对其各种性能参数的自动化测试方法进行了深入研究,并利用LabVIEW虚拟仪器开发平台和仪器总线技术,建立了基于工业控制计算机和数据采集卡的开放式自动测试系统;该系统充分利用了信息处理板DSP芯片的强大运算能力,确保系统具有很快的测试速度和很高的测试精度;自动测试系统的成功应用,大大提高了对信息处理板的测试水平。     

基于机器视觉和力反馈的自动装配技术研究

针对工业生产中自动装配技术装配精度不高的问题,提出了一种基于机器视觉和六维力传感器的自动装配控制方法。使用两个单目摄像头对目标进行两次定位,通过改进的NCC匹配算法进行一次定位,通过基于边缘特征的模板匹配进行二次定位,利用六维力传感器获取装配过程中的力与力矩变化情况,并基于反馈的力与力矩提出了直线运动与螺旋线运动两种装配轨迹规划策略。在搭建的机器人平台上对两种策略进行了对比实验,实验结果表明,在轴孔间隙较大时直线运动装配效率较高,但当轴孔间隙小于0. 1 mm时,直线运动的装配效率和成功率均大幅下降,而螺旋线运动的装配时间主要与装配孔直径有关,对于不同轴孔间隙装配表现稳定,并能以较高成功率实现精度0. 05 mm的轴孔装配。     

中职计算机组装与维护教学策略分析

近年来,随着我国教育体制改革的不断深化以及计算机网络技术的普及应用,使得计算机组装与维护教学越来越受到人们的关注。作为一门计算机专业中是一门工具类课程——计算机组装与维护,是中职教学中不可或缺的重要课程之一。然而,目前的教材和现有的主流硬件完全不符,跟不上计算机发展的步伐,难以满足计算机组装与维护的要求,需要人们对其教学模式进行改革。本文主要是对我国中职计算机组装与维护教学进行探讨分析,从中找出问题所在,并提出相应的解决策略。     

Application of robots in assembly automation

The development of flexible assembly is closely related to the introduction of robots in assembly automation. If has long been recognized that automatic parts assembly by robots is one of the most delicate and most difficult tasks in industrial robotics. This task involves two control problems, trajectory planning for the whole automatic assembly process and reduction of the reaction forces appearing between the parts being assembled. This paper addresses both aspects of this control task. The strategical control level for the manipulation of robots and various approaches to trajectory planning tasks in assembly processes are discussed. A new approach to the determination of the strategical control level, including various models (geometric, kinematic and dynamic) for manipulation robots, is briefly described.The last and most delicate phase of the assembly process is parts mating, which is rather like inserting a peg in a hole. In order to reduce the reaction forces appearing between the parts being assembled, force feedback control is applied. The experimental results of the industrial robot insertion process with force feedback are also presented in the paper.     

基于SolidWorks 的可视化定制研究

针对可视化定制系统中如何实时自动装配和交互浏览的问题,提出一种基于 SolidWorks 二次开发自动装配的方法。用户在网页上确定定制方案后,服务器端和与服务器有 固定联系的一台主机远程通讯,对SolidWorks 二次开发后的自动装配程序安装在此主机上,服 务器端远程启动主机上的自动装配程序,并接收装配完整的eDrawings 文件,将三维模型反馈 到网页上显示,用户可以在网页上实现虚拟交互浏览。该方法可以实现三维模型在多选择方案 下的实时自动组装和网页上的虚拟交互。     

Augmented Reality (AR) for Assembly Processes Design and Experimental Evaluation

Augmented reality (AR) for assembly processes is a new kind of computer support for a traditional industrial domain. This new application of AR technology is called ARsembly. The intention of this article is to describe a typical scenario for assembly and service personnel and how they might be supported by AR. For this purpose, tasks with different degrees of difficulty were selected from an authentic assembly process. In addition, 2 other kinds of assembly support media (a paper manual and a tutorial by an expert) were examined in order to compare them with ARsembly. The results showed that the assembly times varied according to the different support conditions. AR support proved to be more suitable for difficult tasks than the paper manual, whereas for easier tasks the use of a paper manual did not differ significantly from AR support. Tasks done under the guidance of an expert were completed most rapidly. Some of the information obtained in this investigation also indicated important considerations for improving future ARsembly applications.     

小型水库土坝安全自动监测系统软件

为了解决小型水库土坝安全状态的自动监测问题,研制了以工控机为主机的电脑自动监测系统,为该系统做了软件设计及编制工作。软件的功能包括数据的自动采集及人工输入、数据的处理与储存、数据的显示及查询、打印、重要数据的趋势图以及部分数据的统计。并给出了系统软件运行的一些重要部分的效果。     

复杂装配体多层次装配路径规划研究

针对传统装配路径规划方法应用于复杂装配体时出现的组合爆炸问题,提出了一种基于人机交互的改进A-Star(A*)算法多层次装配路径规划方法。算法在传统启发式路径规划算法的基础上引入了干涉威胁概率、平滑度代价、权重系数参数,实现了算法不同侧重方向的最优路径寻找。算法首先根据基于人机交互的路径规划方法结合操作者的装配经验将复杂装配体划分为多个装配层次段,其次对各层次段中的装配零部件运用改进A*算法求解最优拆卸路径,并最终根据路径反演原则生成整个复杂装配体最优装配路径。结合算法仿真对比与KUKA工业机器人路径规划实例验证,得出上述方法较传统启发式路径规划方法提升了路径规划效率,满足了工业生产中复杂装配体自动路径规划需求。     

Automatic assembly simulation of product in virtual environment based on interaction feature pair

In engineering practical implications, assembly simulation is a useful solution to test the planned assembly process and address assembly issues. However, it is usually carried out by time-consuming human–computer interaction, which causes a lot of unavoidable laborious work. Assembly simulation could exhibit the design intent in virtual environment through the interactions between parts. Unfortunately, the models which modeled with current constraint-based method cannot provide sufficient interaction information to support assembly simulation, and the needed information should be added by designers manually. To solve this problem, this paper introduces the concept of interaction feature pair (IFP) and presents an automatic assembly simulation method based on IFP. The proposed IFP provides a form that endues a part with the capability of knowing which part is going to interact with and how to interact. Based on IFP, the automatic assembly simulation is carried out in two steps: First, a graph-based method in presented to generate the interaction sequence, which provides the information that when and which feature should be mated during assembly. Then, the randomized motion planning is employed in the established C-space to find a collision-free path for each part, and the planning results in C-space are transferred into the movements of parts in simulation environment. With these two steps, the parts could interact with other parts under a certain interaction sequence, which automatically simulates the assembly of the product. Finally, an implementation sample is presented and the results show the effectiveness of the proposed method.     

基于网络的新型计算机考试系统

在概念计算机考试现状的基础上,介绍了一种基于网络的具有主观题自动出题自动阅卷功能的新型计算机考试系统,该系统实现了从出题到考试到判卷的整个过程均由计算机完成,对系统的结构,基本功能和实现方案作了介绍,论述了其自动出题和自动阅卷功能的实现策略,并以Windows95/98和MsOffice模块为例,说明了自动阅卷的具体实现。     

Single assembly sequence to flexible assembly plan by Autonomous Constraint Generation

The factory of the future is steering away from conventional assembly line production with sequential conveyor technology, towards flexible assembly lines, where products dynamically move between work-cells. Flexible assembly lines are significantly more complex to plan compared to sequential lines. Therefore there is an increased need for autonomously generating flexible robot-centered assembly plans. The novel Autonomous Constraint Generation (ACG) method presented here will generate a dynamic assembly plan starting from an initial assembly sequence, which is easier to program. Using a physics simulator, variations of the work-cell configurations from the initial sequence are evaluated and assembly constraints are autonomously deduced. Based on that the method can generate a complete assembly graph that is specific to the robot and work-cell in which it was initially programmed, taking into account both part and robot collisions. A major advantage is that it scales only linearly with the number of parts in the assembly. The method is compared to previous research by applying it to the Cranfield Benchmark problem. Results show a 93% reduction in planning time compared to using Reinforcement Learning Search. Furthermore, it is more accurate compared to generating the assembly graph from human interaction. Finally, applying the method to a real life industrial use case proves that a valid assembly graph is generated within reasonable time for industry.     

Multiobjective constructive heuristics for the 1/3 variant of the time and space assembly line balancing problem: ACO and random greedy search

In this work we present two new multiobjective proposals based on ant colony optimisation and random greedy search algorithms to solve a more realistic extension of a classical industrial problem: time and space assembly line balancing. Some variants of these algorithms have been compared in order to find out the impact of different design configurations and the use of heuristic information. Good performance is shown after applying every algorithm to 10 well-known problem instances in comparison to NSGA-II. In addition, those algorithms which have provided the best results have been employed to tackle a real-world problem at the Nissan plant, located in Spain.     

The MARK III flexible automatic assembly cell

MARK III is a new concept in flexible automatic assembly (FAA) cells and has technically evolved out of the MARK II concept. The MARK III FAA cell is stepwise upgradeable and enables a major reduction in the cost of feeders and programming. It is a hybrid cell, combining automatic and manual assembly. The cell consists of a railtrack-mounted robot and adopts the sub-batch principle. Developed in order to account for the assembly of a vast range of products and variants, the MARK III allows for near-zero changeover times. By incorporating free-coupled manual assembly stations, the stepwise automation of manual operations is supported. These factors permit the automatic assembly of products with an annual volume normally too low to justify automation. Likewise, MARK III offers excellent opportunities for gradual capacity increase. Furthermore, it can account for unpredictable order schemes. The MARK III FAA cell also adopts a new programming and control system (FACE) which enables a drastic reduction in programming costs. This paper describes the evolution of this FAA cell from research to industrial launch.     

基于组态软件和PLC的锅炉水处理自动监控系统

介绍了集工业控制计算机、MCGS组态软件、PLC、变频器于一体的锅炉水处理自动监控系统.此系统实现了数据的集中管理、自动控制、故障检测等多方面功能,为锅炉的连续、稳定、安全运行提供了保证.     

Issues related to the computer realization of a multidisciplinary and multiobjective optimization system

Issues and novel ideas to be considered when developing computer realizations of complex multidisciplinary and multiobjective optimization systems are introduced. The aim is to discuss computer realizations that make possible both computationally efficient multidisciplinary analysis and multiobjective optimization of real world problems. We introduce software tools that make typically very time-consuming simulation processes more effective and, thus, enable even interactive multiobjective optimization with a real decision maker. In this paper, we first define a multidisciplinary and multiobjective optimization system and after that present an implementation overview of such problems including basic components participating in the solution process. Furthermore, interfaces and data flows between the components are described. A couple of important features related to the implementation are discussed in detail, for example, the usage of automatic differentiation. Finally, the ideas presented are illustrated with an industrial multiobjective optimization problem, when we describe numerical experiments related to quality properties in paper making.