Inspecting Natural and Other Variable Objects

This chapter is concerned with the design of artificial vision systems that attempt to emulate one particular human activity: inspecting and manipulating highly variable natural objects and human artifacts. During the last quarter of the twentieth century and the first decade of the twenty-first century, Machine Vision, evolved from an exotic technology, created by academics, into one that is of considerable practical and commercial value, and which now provides assistance over a wide area of manufacturing industry. Hitherto, Machine Vision has been applied extensively in industry to tasks such as inspecting close tolerance engineering artefacts, during or shortly, after, manufacture. However, Machine Vision technology can also be applied to those areas of manufacturing where natural materials and other highly variable objects are processed. Our discussion in these pages is aimed at those areas of manufacturing where wide tolerances are encountered, as well as activities, such as agriculture, horticulture, fishing, mining, etc., where similar conditions apply. However, we should not lose sight of the fact that certain so-called high-precision industries are plagued by significant degrees of uncertainty. For example, the electronics industry is renowned for working with high-precision components (integrated circuits, printed circuit boards, etc.). However, it is also concerned with highly variable entities such as solder joints, flexible cables and components with flying-lead connectors (resistors, capacitors, diodes, coils, etc.). This chapter is relevant to applications such as these, as it is to examining fruit, vegetables, animals, fish, etc.