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Describes a three‐dimensional machine vision technology for inspecting and measuring on‐line production. States that the 4DI three‐dimensional imager, a new machine vision technology developed by Intelligent Automation Systems, combines speed and accuracy to perform 100 per cent on‐line inspection and measurement of volumes and surfaces in real‐time. Until recently, neither conventional measurement techniques such as co‐ordinate measurement machines nor non‐contact optical technologies could inspect 100 per cent of production on‐line three‐dimensionally, being either too slow or too sensitive to ambient light. The 4DI uses structured laser light, multiple cameras and triangulation to capture moving or stationary objects. States this technology allows objects of different sizes, ranging from several feet to fractions of an inch to be imaged. States the system has no moving parts, it is robust in industrial environments.

Description of current 4DI three dimensional imaging system, a proprietary 3D vision sensing technology available from Intelligent Automation (IA), and introduction to the recently developed, next generation, HiPART (High‐resolution Phase Angle Resolved Triangulation) gauge sensor developed by a consortium in which IA participated. Both are non‐contact electro‐optical systems capable of being applied to a wide realm of inspection possibilities for the metrology industry. The HiPART sensor is one of the key non‐contact measurement technologies developed by potential end‐users of the technology, high‐technology advancement companies, and the US government in a collaborative effort to improve the measurement and inspection processes of manufactured parts. Specifications and benefits of the sensors, and examples of possible uses are outlined, illustrating the advantage that the 4DI and HiPART sensor have over standard coordinate measuring machines (CMMs). These sensors are actively being commercialized by IA, a custom automation and machine vision development company, which is introducing it to the appropriate markets.

Inspection is an activity that controls the outgoing product quality and involves search, detection and measurement or diagnosis. Traditionally, inspection tasks have been allocated to humans. Attempts to automate industrial inspection in order to eliminate errors and alleviate monotony have faced difficulties due to technological limitations and/or prohibitive implementation costs. An occasional compromise is partial automation (hybrid inspection). Reviews published research in manual, hybrid and automated inspection to understand the current research status.

Optical measurement sensors are increasingly available, often finding application in measurement and inspection of manufactured products. For example, theodolites and laser trackers are already used to calibrate jigs and tooling. Digital photogrammetry is used in dimensional inspection of assemblies such as aircraft wings. Such tasks demand high performance sensors with 2D and 3D capability, large working envelopes, high accuracy, low measurement latency and increased flexibility. The availability of sensors which meet and exceed such criteria is fuelling new possibilities in the manufacturing process itself. Fixed tooling may be eliminated and replaced by flexible fixturing under the control of embedded sensor systems. Sensor technology is reviewed and a novel application presented.

The purpose of this paper is to develop a wireless positioning system. The automation of non-destructive testing (NDT) of large and complex geometry structures such as aircraft wings and fuselage is prohibitively expensive, though automation promises to improve on manual ultrasound testing. One inexpensive way to achieve automation is by using a small wall-climbing mobile robot to move a single ultrasound probe over the surface through a scanning trajectory defined by a qualified procedure. However, the problem is to guide the robot though the trajectory and know whether it has followed it accurately to confirm that the qualified procedure has been carried out.

The approach is to use sophisticated bulk electronics developed for game playing in combination with MATLAB to develop a wireless positioning system.

The paper describes the development of an inexpensive wireless system comprising an optical spatial positioning system and inertial measurement unit that relates the 3D location of an NDT probe carried by a mobile robot to a computer-aided drawing (CAD) representation of the test structure in a MATLAB environment. The probe is located to an accuracy of ± 2 mm at distances of 5 m.

Positioning range is limited to 5 m. Further development is required to increase this range.

The wireless system is used to develop tools to guide the robot remotely to follow a desired scanning trajectory, obtain feedback about the actual trajectory executed by the robot, know exactly where an ultrasound pulse echo was captured, map identified defects on the CAD and relate them to the real test object.

An inexpensive spatial positioning system with sufficient accuracy for automated NDT purposes.

The application of objective measurement of the mechanical properties of fabrics in the apparel industry began around 1975 in the Hirakata area, which is one of the centres of men's suit production in Japan. At that time the KESF system had been developed and thereafter spread rapidly. The measurement of mechanical data under low‐load level by the KESF provided useful information for the apparel engineers who needed some means of fabric measurement by which the tailoring process might be controlled. The fabric dimensional stability testing using steam press was also standardised at that time (HESC 103A method). At present, the KESF data and the stability data are essential for apparel engineers and are used widely in the Japanese apparel industry. In addition to the use of objective measurements in each factory, a centre for objective fabric inspection has been recently initiated in the Hirakata area, for the inspection and control of fabric by the objective system for tailoring process control. In addition, a co‐operative work between the apparel engineers and the university has been carried out to develop a new equation for predicting the good appearance of a suit on the basis of fabric mechanical data. Automatic tailoring such as automatic overfeed action on the basis of fabric mechanical property is also carried out under the co‐operation of the university, the apparel industry, and a sewing machine manufacturer (Juki) in Hirakata. The progress of these projects is presented.

The problem of automating visual inspection is considered along with the developments that are likely to occur.

Manufacturers are now driving towards the increased use of automation and the goal of zero‐defects. As quality is improved and defect rates approach the popularized “Six‐sigma” level (customarily 3.4 defects per million), manual or sampled measurement techniques limit the achievement of product quality and manufacturing cost objectives. New automated inspection and gauging technology is required for process verification and control. To be competitive in the current manufacturing environment, new gauging technology must be integrated into the manufacturing process to provide online feedback.