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The purpose of this paper is to review the progress of machine vision as it applies to automated assembly applications.

A series of technological developments is described: 3D vision, smart cameras, near infrared (NIR) imaging and LED illumination. Associated with each are relevant assembly applications.

Advances in multi‐core processors are facilitating the development of 3D image processing algorithms for robot guidance and product inspection, which in turn enable the automation of skilful and labour‐intensive tasks. Machine vision products are becoming more capable, yet simpler to use. NIR imaging is useful for inspecting semiconductors and bottle filling. Advances in LED lighting address difficult inspection tasks at the macro and microscopic levels.

The paper recognises the emergence of 3D machine vision as a new tool in assembly automation. Updates engineers on other relevant machine vision advances.

Product quality inspection is of importance in manufacturing industries to ensure that low quality or unqualified products are not delivered to the consumer. Human inspection has many limitations such as low accuracy or speed due to factors such as tiredness and boredom. Traditional 2D vision inspection also has limitations of product shape complexity or flexibility. Thus, automated 3D vision inspection is anticipated to meet the requirements of higher applicability. This paper seeks to address these issues.

In many product quality inspection problems, geometrical parameters of the industrial parts are commonly used as the basis of quality inspection. Machine vision is widely applied to acquire such kind of parameters. Comparing to traditional 2D vision, 3D vision can acquire 3D coordinates of the object directly, so that the inspection can be accomplished which is difficult to do with 2D vision. As an active vision technique, structure light system (SLS) is applied to acquire the 3D coordinate information of inspected object in this paper. On the basis of point cloud and regression analysis, features relative to quality are defined and extracted as the attributes for the product classification. Three data mining techniques are applied to accomplish the classification in this paper, which include decision trees, artificial neural networks and support vector machine.

A new intelligent automated 3D vision quality inspection for assembly lines has been developed, which comprises structure light system (SLS) and data mining approaches such as decision tree, artificial neutral networks and support vector machine.

The combination of structure light system (SLS) and data mining approaches makes the automated quality inspection available. The proposed system is easy to be implemented and flexible for different types of products.

Actimed Laboratories Inc., USA, explain how they are using machine vision technology to develop automated inspection systems for home cholesterol‐screening kits.

Describes how a computer disk and storage media company [KAO Infosystems of the USA]uses machine vision technology to maintain the quality of its products by isolating problems and identifying ways of improving the manufacturing process. Emphasises the need to fully define applications and evaluate the technology before introducing a new element to an automation process and stresses the need to integrate the vision system hardware with the plant’s existing manufacturing equipment.

This paper aims to design an automatic inspection system for the characters on tire molds, which involves a vision-based inspection method for the characters on tire molds.

An automatic inspection equipment is designed according to the features of the tire mold. To implement the inspection task, the corresponding image processing methods are designed, including image preprocessing, image mosaic, image locating and character inspection. Image preprocessing mainly contains fitting the contours of the acquired tire mold images and those of the computer aided design (CAD) as the arcs of two circles and polar transformation of the acquired images and the CAD. Then, the authors propose a novel framework to locate the acquired images into the corresponding mosaicked tire mold image. Finally, a character inspection scheme is proposed by combining an support-vector-machine-based character recognition method and a string matching approach. At the stages of image locating and character inspection, image mosaic is simultaneously used to label the defects in the mosaicked tire mold image, which is based on histograms-of-gradients features.

The experimental results indicate that the designed automatic inspection system can inspect the characters on the tire mold with a high accuracy at a reasonable time consumption.

The designed automatic inspection system can detect the carving faults for the characters on the tire molds, which are the cases that the characters are wrongly added, deleted or modified on the tire mold.

To the best of the authors’ knowledge, this is the first automatic vision-based inspection system for the characters on tire molds. An inspection equipment is designed and many novel image processing methods are proposed to implement the inspection task. The designed system can be widely applied in the industry.

Film is an important recording medium in industry. How to ensure film quality is a problem, because the film is produced in a dark room. Aims to focus on this.

An inspection system based on machine vision is presented which could assure illumination and imaging at 940 nm which is safe for film.

An objective evaluation is given using an image processing method and satisfactory results are obtained. Now, the inspection system is used by the biggest film company in China.

This work focuses on an important issue in film production.

This article reviews automatic inspection within the pharmaceutical industry and deals, in particular, with the application of machine vision to these tasks. Although taking some time to be established within this industry, caused, in part perhaps, by unrealistic expectations of the performance available, machine vision systems are now available in a robust and reliable format, ideally suited to the demanding and security‐conscious needs of this sector. Such systems are now addressing a wide variety of applications, often aimed at the packaging, labelling and coding of products where the ever‐more‐stringent requirements of the regulatory bodies provide a considerable impetus to the improvement cycle. Given that effective quality management should recognize that improvements in products and processes should be sought continually, however good they are, all aspects of packaging, labelling and coding should come under scrutiny when the demanding standards of product security are considered. It is perhaps easy to understand why, when the implications of the accidental misuse of a drug could be severe, both in human terms and in the cost of any remedial action necessary. Therefore, in order to assure product security, inspection at strategic points in the manufacturing process will normally be required. However, the drawbacks of human inspectors being used to carry out repetitive inspection are numerous (and probably well known!) but include the maximum concentration span and the unavoidable subjectivity involved.

Outlines some of the areas in machine vision system solution which have seen the most significant advances as a result of technology enhancement and particularly the rapid development in semiconductor technology. Looks at the background of machine vision development and improvements brought about by modern technology, covering advances in vision algorithms, “warp engines” used in combination with an application specific integrated circuit [ASIC], improvements in human interface; and optical character recognition. Concludes that the trend now is for general purpose vision processing systems to provide greater capability, at greater throughput speed, without significantly increasing the cost of the system which means that they are now part of the original process design to inspect critical stages of manufacture.

Reports on the exhibits and exhibitors at Manufacturing Week, which took place at the NEC, 10‐12 November 1998. It reveals that machine vision is the major attraction at the show with over a quarter of the exhibitors exhibiting activity in this area. A number of the companies who offer turnkey systems are highlighted; some include vision as an element in their systems while others are totally dedicated to application of the technology. The emphasis in the article is on applications with the predominance being for inspection. Brief case studies are given of inspecting automotive switches, a contact lens line, robot grinding of propellers and a seat belt retractor assembly system. Some new products are also described including a “control free” junction for Bosch twin belt pallet conveyors and compact fast camera with integral image acquisition and processing electronics.