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The introduction of time compression technologies into the modern mechanical design process is now well established. Most major automotive and aerospace companies have invested, as have their Tier 1 suppliers. It has been identified that a bottleneck affecting all aspects of the cycle is the measurement process. In this paper we shall discuss potential benefits of adopting non‐contact techniques. In section 1 we discuss the need for rapid physical measurement within the context of the mechanical design process. The processes required for surface creation and inspection are discussed in Section 2 with regard to contact and non‐contact measurement. Section 3 reviews the operating principles of commercially available non‐contact systems. Finally Section 4 discusses practical issues relating to the implementation and use of non‐contact systems in the manufacturing environment.

The purpose of this paper is to provide a comprehensive review of a non-contact full-field optical measurement technique known as digital image correlation (DIC).

The approach of this review paper is to introduce the research pertaining to DIC. It comprehensively covers crucial facets including its principles, historical development, core challenges, current research status and practical applications. Additionally, it delves into unresolved issues and outlines future research objectives.

The findings of this review encompass essential aspects of DIC, including core issues like the subpixel registration algorithm, camera calibration, measurement of surface deformation in 3D complex structures and applications in ultra-high-temperature settings. Additionally, the review presents the prevailing strategies for addressing these challenges, the most recent advancements in DIC applications across quasi-static, dynamic, ultra-high-temperature, large-scale and micro-scale engineering domains, along with key directions for future research endeavors.

This review holds a substantial value as it furnishes a comprehensive and in-depth introduction to DIC, while also spotlighting its prospective applications.

Review of the advancements in non-contact laser sensors for much more accurate real time speed as well as length measurements. The paper aims to discuss these issues.

In-depth review of a number of applications of laser sensors.

A wide range of manufacturers in the converting industries have solved measurement problems and realized major improvements in product quality, cost of production and productivity by applying laser measurement as well as reduction in scrap.

Others with the need to make very accurate measurements of speed and length in real time may find that laser sensors may provide the answer.

An expert insight into how to solve real time speed and length measurement problems.

Aircraft structures are mainly connected by riveting joints, whose quality and mechanical performance are directly determined by vertical accuracy of riveting holes. This paper proposed a combined vertical accuracy compensation method for drilling and riveting of aircraft panels with great variable curvatures.

The vertical accuracy compensation method combines online and offline compensation categories in a robot riveting and drilling system. The former category based on laser ranging is aimed to correct the vertical error between actual and theoretical riveting positions, and the latter based on model curvature is used to correct the vertical error caused by the approximate plane fitting in variable-curvature panels.

The vertical accuracy compensation method is applied in an automatic robot drilling and riveting system. The result reveals that the vertical accuracy error of drilling and riveting is within 0.4°, which meets the requirements of the vertical accuracy in aircraft assembly.

The proposed method is suitable for improving the vertical accuracy of drilling and riveting on panels or skins of aerospace products with great variable curvatures without introducing extra measuring sensors.

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.

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.

Outlines the use of in‐line laser‐based data cameras for adaptive control and robot guidance applications in durable goods manufacturing processes. States that although traditionally such systems were used for quality control applications, they can now be used in many other situations. Describes the use of laser‐based triangulation measurement for adaptive control in the assembly process. Examines typical measurement features, measurement algorithms and software, visual fixturing and a number of applications. Concludes that laser‐based measurements provide rapid, accurate and reliable data and that it will enable automation of numerous processes.

With the rapid advancement of computer information technology, the traditional clothing industry has stridden towards automation and digitization that drive the growth of electronic commerce and line retailing. The purpose of this paper is to propose an approach on 3D upper body modelling based on the body measurements extracted by non-contact anthropometry.

Based on the frontal and side images of the human body, the body sizes were extracted through silhouette extraction, identification of landmarks and girth prediction. The generation rules of 15 characteristic cross-sectional curves were established using a method “feature points – inserted points – feature curves – basic surface – mannequin”. The feature points of each position were determined at each curve, such as the side neck point, front neck point, shoulder point, bust point, and bust root point and so on to get the cross-sections, and then some feature points were inserted at the curves according to the widths and depths to establish the calculative models. For example, there are 18 points distributed at the bust cross-sectional curve to determine the shape.

The final mannequin could describe the basic characteristics of a human body, and the shape of the feature curves could also fit the body type to provide basis for the future research on automatic pattern generation.

This study can realize the 3D virtual modelling of female upper body and the automatic generation of the individualized apparel patterns based on the frontal and side images.

Cylindrical components are common in industry assembly areas. It is necessary to obtain their precise positions and orientations for their assemblies. But some measurement approaches relying on measuring targets are not allowed, as they may not meet the efficiency requirement of on-line measurement or may cause surface damages to the components. Thus, this paper aims to provide a precise on-line non-target scanning method based on 3D vision.

First, a laser profile sensor is used to acquire point cloud of the side surface of the measured cylindrical component. Then a composite process is conducted to estimate the pose and position of the axis. Aiming at this purpose, two fitting approaches, i.e., axis fitting and generatrix fitting, are tried respectively to estimate the pose parameters from the point cloud.

The results of Monte Carlo simulations demonstrate that neither the axis fitting nor the generatrix fitting could solely obtain the needed accuracy and precisions roundly. Thus, a new synthesis method is presented. And the results of prototype experiments validate the excellent accuracy and precision of the synthesis method.

This proposed new synthesis method combines the advantages of both the above fitting methods and can be easily integrated into the assembly line to guide the automation assembly process of the cylindrical components precisely.