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Leg volume (LV) is an important reference in nutrition, physiology in exercise, or clinical diagnosis. Therefore, how to evaluate LV easily and quickly with accuracy is important in these areas. To develop a simple anthropometric estimation formula with ease of use and good accuracy for leg volume (LV) of female labourers. One hundred and thirty female labourers (110 subjects for formula regression procedure and 20 subjects for the comparison phase) were recruited as subjects with no reported leg surgery history, trauma, or deformity. A set of 3 D scanners was used to measure the range data of each subject's leg. The resultant LV estimation formula is LV = 0.215 × LL × CTH1.620 with R2 = 0.967, in which LL stands for leg length and CTH for circumference of thigh. Mean error of this LV estimation is 0.10% and much smaller than that of the previous study (25.11% with significant difference). An anthropometric estimation formula for female labourers' leg volume was developed in this study. Estimation mean error of this formula is much smaller than the one in the previous study. This formula is easy to use and shows good accuracy in estimating female labourers' leg volume. [ABSTRACT FROM AUTHOR]

The lighting condition is critical in the anthropometric scanning process. Optimal lighting condition affects the time and precision. The current study sought to determine the optimal light for measuring the static anthropometric dimensions of feet and hands based on the precision, trueness, and efficiency of EinScan Pro 2X Plus. Three conditions of the scanning process were Light Zero Light/ZL: 5-50 lux, Normal Light/NL: 50-100 lux, and Room Light/RL: 100-200 lux. The data collected and analyzed were 3D model mesh data (point clouds), which were then processed using CAD software for deviation analysis. The precision variable was computed using the pooled standard deviation (Sp) value. The Absolute Error (AE) and Absolute Percentage Error (APE) were used to calculate the trueness variable. The efficiency aspect was measured based on the average value of measurement time. The optimal lighting condition was ZL, which was determined using a simple additive weighting method. The precision of the hand in Sp value was 1.25 mm while the foot precision was 0.92 mm. The hand trueness in AE value was 1.73 ± 1.33, while the foot trueness was 1.34 ± 1.20 mm. The hand efficiency in time value was 273.94 s, and the foot efficiency were 272,94 s. [ABSTRACT FROM AUTHOR]

The design and manufacturing strategy using reverse engineering (RE) for Miranda Kerr Tea for One Teapot are presented in this paper. A computer-aided reverse engineering system (CARE System) was applied to minimize file errors generated by scanning Miranda Kerr Tea for One Teapot sample products made from Bone China clay. Digital data from the scanning process is used to design a teapot model that is precise and accurate. The digital data generated by Next Engine 3D and the priXa 1588 CMM is then converted into stereolithography (STL) file format (triangle-based data). The process of making 3D CAD models consists of: editing the 3D mesh from the scanning results, 3D CAD design forming the size of the fire, the size of the model, and the 3D CAD milling process using PowerSHAPE with the final result in the form of the surface of each part of the Teapot product. Manufacturing optimization to get the optimal machining strategy used PowerMILL and CNC machines. The casting process becomes a follow-up process after machining the mold of the designed product. This research has succeeded in demonstrating the advantages of using CARE System technology in the national ceramic industry in Indonesia so that it can compete at national and international levels. This is based on the magnitude of the RE error value of less than 1.00 mm with a total processing time of 43 hours 18 minutes 10 seconds and a total cost of about $ 4172.35. [ABSTRACT FROM AUTHOR]

In the mining industry, slips and falls are the second leading cause of non-fatal injuries. Footwear is the primary defence against a slip; consequently, the condition of the footwear outsole is critical to maintaining slip resistance. Currently, there is no published method that can be used to determine when the outsole no longer affords adequate slip protection. Moreover, quantifying the condition of the outsole through the measurement of outsole features can be tedious. This article introduces a new method for the quantification of boot outsole wear. Using a handheld 3D scanner, boot scans can be taken quickly and the developed models used to measure outsole features. This method also accounts for the bending of the boot due to normal wear, which may otherwise introduce erroneous measures. When compared to measurements with a traditional handheld calliper, this new method offers more flexibility in terms of data collection, accounts for other types of boot transformations, and is more efficient to use over multiple measurement periods with no statistically significant differences in measurement. [ABSTRACT FROM AUTHOR]

3-Dimensional (3D) scanning systems are becoming more common in the industry nowadays, for inspection and reverse engineering (RE) purposes. Although technical specifications are provided with commercially available scanners, a question could be raised pertaining to the degree of sufficiency of the technical specifications typically provided, with regard to specific application needs such as the scanning of challenging objects. These challenging objects present a less than ideal working condition for some 3D scanners, and the specified accuracy cannot be achieved. This effect varies across different types of 3D scanning technology. A more intuitive specification with regard to the time taken and ease of use will be beneficial to the user, but often not available. Hence, this paper proposes a Morphological Box Classification Framework based on the functional decomposition of the non-contact 3D scanning technology, in order to help users better understand and compare 3D scanners efficiently, and choose a scanner for their application that is able to perform within their desired accuracy, time taken, and ease of use. A case study of 3D scanners evaluation using the proposed framework for a RE application is conducted, and results presented. [ABSTRACT FROM AUTHOR]

The objective of the study is to establish a quantitative relationship between air gap sizes and clothing thermal performance. Using a three-dimensional human body scanner, the thicknesses and volumes of air gaps of 35 experimental shirts were measured. Relationships between the thermal insulations of clothing, measured on a thermal manikin, and air gap volumes were examined by regression analysis. Also, the regression model between clothing surface temperatures, measured by an infrared thermal camera, and air gap thicknesses was established. The results proved that the thermal insulation of experimental shirts increased with air gap sizes but began to decrease as a result of natural convection when the air gap thickness was higher than 1 cm or the air gap volume was greater than 6000 cm3. The 3D human body scanner can accurately measure air gaps under clothing, but it is expensive and is not available everywhere. A substitute method is to build a mathematical model for predicting air gap sizes. In this paper, regression models were established to estimate volumes and thicknesses of air gaps when the ease allowances of chest circumference and fabric properties were known. This study can be used to predict the thermal performance of clothing at the product’s design stage. [ABSTRACT FROM AUTHOR]

This study measured the facial dimensions of Korean Air Force (KAF) pilots, to design a pilot oxygen mask, and compared them with those of Korean civilians and US Air Force (USAF) personnel. Twenty-two facial dimensions were measured for 278 KAF male pilots (KMP) and 58 KAF female pilots and cadets (KFP) using an anthropometer and a three-dimensional scanner. The KMP face measurements were found to be significantly larger (mean difference, = 0.7–26.5 mm) and less varied (ratio of SDs = 0.29–0.82) than those of Korean male civilians. The average face length, lip width and nasal root breadth of the KMP were significantly longer ( = 4.7 mm), narrower ( = − 2.4 mm), and wider ( = 5.2 mm), respectively, than those of USAF male personnel. Lastly, the KMP face measurements were significantly larger ( = 1.8–26.1 mm) than those of the KFP. Practitioner Summary:The face measurements of KAF pilots were collected and compared with those of Korean civilians and USAF personnel. The distinct facial features of the populations identified in this study are applicable to custom design of an oxygen mask for prevention of excessive pressure and oxygen leakage. [ABSTRACT FROM PUBLISHER]

Preoperative, accurate measurement of spatial parameters of the external nose could be essential in the postoperative assessment of rhinoplasty. The aim of the study was to analyse the relevance of three-dimensional (3D) imaging in aesthetic evaluation after operation, to provide a standardised algorithm of nasal shape measurements, which will enable the development of software for assessing the nose before and after rhinoplasty, to perform analysis of spatial changes of both its shape and asymmetry by the new protocol of measurements. Fifty-four patients were examined preoperatively and 6 months postoperatively. The following nasal parameters were determined: rates of proportion, angles, and spatial parameters. After the operation, statistically significant differences were observed in all parameters. In conclusion, a 3D scanner can be used as a tool to assess the results of rhinoplasty. This protocol of measurements describes spatial changes of the nose shape resulting from the operation. [ABSTRACT FROM AUTHOR]

Scaling accuracy is of utmost importance to obtain optimal sawn timber yield in primary breakdown. In this article, sawmill observations, review of available publications and supplementary tests are combined to analyse the accuracy of conifer roundwood scaling. The influence of important log parameters are considered for various scaling technology: one- and two-directional (1Dir and 2Dir) shadow scanners and three-dimensional (3Dim) reflected beam scanners. Standard error for each of the terms, ovality, bark and scanner technology, is discussed. The overall accuracy for diameter under bark can be calculated by adding the variances for each independent term. Results show that for unbarked logs, 2Dir shadow scanner remains the most accurate technology. For barked logs, 3Dim reflected laser beam scanner combines the highest accuracy and the ability of providing a wide range of important log parameters. For a case study sawmill, annual roundwood consumption are reduced by 2.0% by transferring from scaling unbarked logs in a two-dimensional shadow scanner to 3Dim scanning of barked logs, while keeping the volume yield of the sawn timber. [ABSTRACT FROM AUTHOR]

Currently, the production of a high-quality and highly aesthetic prosthesis is still mainly based on handwork and subjective comparison to get the proper shape and colour of the prosthesis, likely not by a first attempt. This article describes a case study whose goal was to investigate the possibilities of computer-aided surface reconstruction and supplementation to improve the quality and reduce the manufacturing time for an orthopaedic prosthesis. For this purpose, a model of human finger made of plaster had been scanned with the high fidelity laser triangulation scanner. The result was a set of very dense point clouds, representing the surface of the finger model in all its complexity. The main target of this work was to create a water-tight, high resolution computer model of a human finger, which would be ready for further manipulation, such as scaling, mirroring or stretching in arbitrary dimensions. A larger amount of such models could represent a virtual database of human shapes, which would be suitable for prosthesis production and many other (medical) purposes. The first steps after scanning were done in an attempt to reorient several scans, taken from different viewpoints, relative to each other in order to get the proper shape of a finger. This was done by applying an ICP algorithm, integrated in commercial software, and its comparison to the results of reorientation, based on information about finger's position transformation during the scanning process. This information proved to be vital for a fast and accurate alignment of the scans and successful surface generation. This paper also discusses the possibilities of avoiding the influences of geometric errors, generated by a triangulation scanner on surface alignment and the creation of a 3D model. The surface was created by applying Delaunay triangulation to the point cloud. Afterwards, it was followed by manual and automatic refining and reconstruction of a triangular mesh. The final result is a 3D computer model of a human finger with all its details, such as fingerprints and wrinkles. Additional measurements showed that the arithmetical average of deviation between a computer and a physical model was less than 0.3 mm, which is a good result for the desired purposes. The study also showed the possibilities for acceleration of scan alignment while the accuracy could be increased. [ABSTRACT FROM AUTHOR]

In the forestry-wood chain the concept and the technologies of traceability are in a mature development phase. Important advances in marking and reading techniques have been made in different parts along the forestry-wood chain. For Swedish sawmills the most critical information gap is located between the log sorting station and the saw intake, where the forest log batch identity disappears and the logs are mixed according to different sorting criteria. This study utilizes radiofrequency identification tags for automatic log marking/reading to develop a traceability system for logs, which is free of marking/reading, between the log sorting station and the saw intake, i.e. the fingerprint method. The originality of the fingerprint approach rests on the hypothesis that logs are separate entities with individual features. The results show that the log parameters and the search algorithm developed, combined with the negative influence of the measurement uncertainty due to bark thickness and bark damage, made it possible to achieve an individual separation for 57% of the tested logs. [ABSTRACT FROM AUTHOR]