Machine vision for industry

Nowadays, industry is changing its way of working in order to get more competitive. Industry wants to get more and more automated in order to reduce production times, increase productivity, improve quality production, at a cheaper cost, to be less wasteful, with less need to have a skilled operative, to be more flexible meaning easy to implement changes and possible to leave the automated process working with little supervision around the clock. Vision in Robotics helps controlling production in a relatively simple form, avoiding a skilled operative to spend his time ‘watching’ the machine doing his job. Moreover, the automatic inspection process does things faster and with improved quality than a human. Robotics Vision and Image Processing tools are the most desired tools for quality control in industry. With the use of one (or more) cameras, and a computer controlling and analysing the extracted images, a software tool can solve a problem in a relatively easy way. An initial investment is needed to buy all the necessary Vision Hardware, but software can be built by using a few existing tools. Instead of making a vision based program from scratch (re-inventing the wheel) to solve a specific problem, it is now possible to use existing image processing tools and build quickly and easily a software solution. These tools work on grey-scale image processing level. These high-level vision software tools do not require that the developer program at the pixel level, which makes the technology accessible even to users with little machine vision experience. To reduce the amount of image to analyse, the user can work on ‘regions of interest’, reducing though the time and space to analyse/store the image. A description of the most important tools are described and its basic principle of functioning is explained. These tools can then be integrated and work together in order to make the full solution

Automação da medida de rectilinidade de vigas de aço com ferramentas de processamento de imagem

Para medir a rectilinidade de vigas de aço em movimento, foi desenvolvido um método e foi construida uma máquina de inspeção com ferramentas de processamento de imagem para a controlar. O método consiste em desenvolver um software específico para executar três tarefas: leitura da posição das vigas em vários pontos do seu percurso, co-relacionar todas essas posições captadas pelas câmaras, e dar a conhecer a rectilinidade final das vigas. A máquina de inspeção usa tecnologia de visão por computador como dispositivo de medida sem contacto. No seu ambiente de produção, as vigas rolam num tapete rolante e portanto várias câmaras de vídeo são usadas para registar informação, não apenas da sua posição lateral mas também da sua altura. O utilizador pode decidir o número de câmaras e a distância a usar entre elas. Caso uma câmara falhe a leitura da posição da viga, ou caso esta esteja desligada (avariada), o sistema de medida não é afectado, desde que haja um mínimo de três câmaras a extrair pontos aceitáveis. O resultado deste sistema é o desvio da não-lineariedade da viga, depois de compensados factores tais como o movimento lateral ou angular no plano de medida horizontal e o perfil da viga. O resultado é mostrado no ecrã de um computador, de acordo com o método das linhas e o método dos quadrados mínimos.For measuring the straightness of moving steel beams, a methodology was developed and an inspection machine was built with a set of image processing tools to control it. The method consists in developing a specific software to perform three main tasks: reading the position of the beams in several positions; correlating all those positions monitored by the cameras; and reporting the quality of the beam straightness. Computer vision technology as a non contact measuring device is used by the inspection machine. From the production process the beams roll on a conveyor therefore several video cameras are used to log information not only about the lateral position but also the height of the steel beams. The user can decide the number of cameras and the distance between them. Should one camera fail or be switched off, the measuring system is not affected as long as the system has a minimum of three cameras extracting acceptable points. The system output is the non linearity deviation of the beam, compensating factors for lateral or angular movements in the horizontal measuring plane of the beam and the beam profile. The output is displayed in a computer screen, according to the line method and the least square method

Open and closed industry clusters: The social structure of innovation

In this paper we discuss knowledge and innovation in clusters and the benefits of clustering from a knowledge-based perspective. Knowledge-based resources and innovations are important sources of competitive advantage for firms. Aware of the importance of continuously seeking new knowledge firms increasingly seek knowledge-rich locations such as specific industry clusters across the world. These are locations characterized by the concentration of firms operating in related and supporting activities, a specialized work force and a specialized institutional environment that nurtures the industry. However, it is not likely that these clusters are always locations from which the firms will be able to draw the intended knowledge benefits. The social structure of the relationships between individuals and firms determines the extent to which knowledge will be created, will flow between co-located firms and bounds the knowledge benefits the firms may capture. We finish with a discussion of the need of further examination of the network dynamics involved in an industry cluster to obtain a clearer identification of the actual positive externalities that may accrue to co-locating firms.Strategy; Industry clusters; Innovation

Making components with controlled metal deposition

Rapid Prototyping is a recent CAD/CAM/CIM based manufacturing technique which produces prototypes of components in a fraction of the time. This technique works by first drawing the part as a 3 Dimensional solid model using a CAD program and then ‘printing’ it in 3 Dimensions. The raw material can be a photopolymer or thermoplastic which solidifies when in contact with light. Other materials are available although 100% metal is not a very usual one. This paper presents a new approach for a Rapid Prototyping technique which uses Robot Fusion Welding. The component is drawn as a 3D solid in a CAD package, and this is then electronically sliced in order to automatically generate the robot path. The welding parameters are also generated according to the desired material/thickness of the component. By serial link RS-232-C, the robot program is then downloaded. This process works unmanned and proved to be good enough for the purpose. This technique can be used to make not only the prototype but also the final component with the desired metal. Therefore, this represents also a new production technique more suitable for low volume production. Another advantage with this new technique is that different metals can be used during the build up of the component to achieve different structural characteristics in different parts of the same component. This would not be possible with casting. The welding can be stopped at any time, the filler material changed, and the welding started again. The wire can be changed quickly. The process created is hereby described as well as its advantages and disadvantages. Some case studies are carried out and described. Several other case studies were carried out and published in order to fully test this system and some references are made to those publications in section IV

Localization of a mobile autonomous robot based on image analysis

This paper introduces an innovative method to solve the problem of self localization of a mobile autonomous robot, and in particular a case study is carried out for robot localization in a RoboCup field environment. The approach here described is completely different from other methods currently used in RoboCup, since it is only based on the use of images and does not involve the use of techniques like Monte Carlo or other probabilistic approaches. This method is simple, acceptably efficient for the purpose it was created, and uses a relatively low computational time to calculate.Fundação para a Ciência e Tecnologia (FCT) - projecto POSI/ROBO/43892/200

Robôs de serviços

Há séculos que as pessoas têm vindo a criar mecanismos para imitar partes do corpo humano. Estes mecanismos têm vindo a ser melhorados através dos tempos e os mais recentes são chamados Robôs. Devido ao avanço tecnológico dos ultimos anos, quer na área da informática quer na área da electrónica, os robôs tem vindo a evoluir apenas recentemente de uma forma mais significativa

Welds prototype rapid exhaust parts: the latest technique for rapid prototyping builds up parts in welded metal

By depositing a continuous bead of weld metal, it is possible to build up rapid prototyped parts in steel to almost any size. The technique is already being used by an unnamed aerospace company and shows potential for making prototyped parts for exhaust systems. It can be applied to almost any weldable metal or combination of metals. Dr Antonio Fernando Ribeiro, formerly at Cranfield, but now at the University of Minho in Guimarães, Portugal, has developed a technique for building up metal parts using robot welding. The process works in essentially the same way as any other layer-by-layer rapid prototyping technique, except that the usual plastic deposition processing equipment is replaced by a rotatable table, a robot arm and an arc welding torch

Automation of beam straightness measurement with image processing tools

For measuring the straightness of moving steel beams, a methodology was developed and an inspection machine was built with a set of image processing tools to control it. The method consists in developing a specific software to perform three main tasks: reading the position of the beams in several positions; correlating all those positions monitored by the cameras; and reporting the quality of the beam straightness. Computer vision technology as a non contact measuring device is used by the inspection machine. From the production process the beams roll on a conveyor therefore several video cameras are used to log information not only about the lateral position but also the height of the steel beams. The user can decide the number of cameras and the distance between them. Should one camera fail or be switched off, the measuring system is not affected as long as the system has a minimum of three cameras extracting acceptable points. The system output is the non linearity deviation of the beam, compensating factors for lateral or angular movements in the horizontal measuring plane of the beam and the beam profile. The output is displayed in a computer screen, according to the line method and the least square method

Rapid prototyping using robot welding

La raison d’être d’un prototype ne devrait pas être seulement la visualisation, mais aussi la possibilité de réaliser des tests et d'ávaluer la pièce dans ses fonctions finales. Ainsi, il est important de réaliser le prototype dans le même matériau que celui de la pièce finale. De plus, afin de contourner les inconvénients des procédés actuels de prototypage rapide, une technique de prototypage rapide basé sur le soudure à l’arc robotisée (Robotic Arc Welding) a été mise au point. Un robot maintenant une torch de soudage est utilisé pour “dessiner” la forme désirée et doit être déplacé de manière répétitive et très précise. Il est important de noter qu’un prix faible était un des objectifs de ce projet.The reason for making a prototype, should not only be to visualise but also usable to test and assess it in its final function. Therefore, it is important to make the prototype with the same material used in the real and final component. Also, to overcome the actual Rapid Prototyping processes disadvantages, a technique for rapid prototyping components using Robotic Arc Welding has been created. For making the component, a robot holding a welding torch is used to "draw" the desired shape and this has to be moved around in a very precise and sometimes repetitive way. It is important to note that low price was a target to achieve in this project