Three-dimensional Measurement Device Research Articles

In Situ Cutting Methodology with 3D Measurement of Block Excesses in Shipbuilding

_ The ship construction process is characterized by a sequential workflow, with pivotal workstations‡ playing a crucial role. Initially, steel plates are introduced to these stations in sheet form, undergoing a transformation process that culminates in the creation of segments known as blocks. These blocks are individually constructed and subsequently assembled at the final workstation, denoted as the block joining station. Upon completing block fabrication, a deliberate tolerance allowance is retained on the plates to accommodate deformations induced by heat treatment during the transformation from plates to blocks. The alignment process involves aligning the reference points (master reference line) of the blocks on a common axis, facilitating the identification of excess material and deformations. This alignment process encompasses aligning the blocks with each other, employing either a three-dimensional measurement device or manual methods to obtain necessary measurements for determining excess material. In an effort to optimize time spent on block alignment and machine usage, a comprehensive methodology has been developed. This methodology involves determining excess material cuts on the blocks, performing virtual alignment operations using laser scanning techniques in a virtual environment, and conducting the cutting process on the slipway prior to placing the block excesses on it. Keywords block excesses; scanning techniques; three-dimensional scanning technology

Research on Wireless Power Transmission Technology for Underground Deformation Three-Dimensional Measurement Device

Research on Wireless Power Transmission Technology for Underground Deformation Three-Dimensional Measurement Device

Comparison of the accuracy of different handheld-type scanners in three-dimensional facial image recognition.

Handheld-type scanners are widely used in clinical practice. This study examined the accuracy of handheld-type scanners using plaster statues to assess their performance in facial recognition. Twelve 4-mm zirconia balls as measuring points were attached to the facial portions of three types of plaster statue. Six digital facial images of each plaster statue were obtained using one of the following five handheld-type scanners: Artec Eva, Artec Spider, Bellus 3D FaceApp, SNAP, and Vectra H1. Four-millimeter spherical objects were manually placed at the measurement points on the scanned data generated using computer-aided design software and coordinate positions were measured using a contact-type high-resolution three-dimensional measurement device. Consequently, the discrepancy between the distance measured using the contact-type device and that measured using the handheld-type scanner was calculated. The scanning time, processing time, and deviation of the distance between the measuring points were analyzed using two-way analysis of variance and t-test with Bonferroni correction. The scanning and processing times ranged from 15.2 to 42.2 s and 20.7 to 234.2 s, respectively. Overall, 97% of all measured distances by Spider were within ±1.00% deviation; 79%, Vectra; 73%, Eva; 70%, Bellus; and 42%, SNAP. The performance of handheld-type scanners using plaster statues varied among the different scanners. The scanning time of Eva and the processing time of Bellus were significantly shorter than those of other scanners. Furthermore, Spider exhibited the best accuracy, followed by Eva, Vectra, Bellus, and SNAP.

Three-Dimensional Acoustic Device for Testing the All-Directional Anisotropic Characteristics of Rock Samples

Many oil and gas fields, especially non-conventional shale and compacted sand reservoirs, have formation anisotropy. The acoustic anisotropy measurement of cores in these reservoirs can guide drilling, well logging, and exploitation. However, almost all core holders are designed for cylinder cores, which are not suitable for all-directional measurements. A three-dimensional measurement device was designed on the basis of the cross-hole sonic logging method. This device mainly consisted of two pairs of transducers, a signal generator, an oscillograph, an omnidirectional positioning system, and a computer control system. By adjusting the measurement latitude and longitude circle automatically, this device scanned spherical sample rocks and obtained full-wave waveforms in all directions. Experiments were performed taking granite from the Jiaodong Peninsula, China, as an example, and the arrival times and velocities of the longitudinal and shear waves were calculated based on the full-wave waveforms. Thereafter, anisotropic physical characterizations were carried out on the basis of these velocities. These data play an important role in guiding formation fracturing and analyzing the stability of borehole walls.

Examination of facial measurement on the image using a noncontact three-dimensional measurement device.

Producing dentures for edentulous patients is important to improve quality of life of elderly. The determination of the occlusal vertical dimension on producing dentures is one of the key factors for using the dentures comfortably. The purpose of this study is to consider the usefulness of the determination of the occlusal vertical dimension of a facial measurement method applied on scanned facial image using a noncontact three-dimensional measurement device. Twenty-four dentulous individuals (mean age 26.6 ± 2.4 years old) were examined in this study. A noncontact three-dimensional measurement device was used for the scanning of the face both in the holding by hand and the fixing to the camera stands situations. The distances between subnasal and gnathion, pupil and oral slit, middle of glabella and subnasal, and right and left corners of the mouth were measured on the scanned face image and compared with the actual values. The significant differences were not recognized on the four measurement items between the distance of actual values and obtained on scanned data (fixing conditions). The coefficients of variation of the distances between subnasal and gnathion, and pupil and oral slit on scanned data (fixing condition) were significantly lower than those at actual conditions (P < 0.05). The results of this study suggested that a stable facial measurement can be successfully implemented by using a noncontact three-dimensional measurement device. This method yields outcomes which match the actual values.

Evaluation of the measurement precision and accuracy in the dental CAD/CAM system.

The purpose of this study is to investigate the precision and trueness of the occlusal contact record obtained with a dental CAD/CAM device (ARCTICA). Sandblasted spherical steel balls with diameters of 10-20 mm were measured using ARCTICA and a three-dimensional measurement device (FN503). The radius of each steel ball was calculated from the measured value and the difference between the measured and nominal values was obtained. Upper/lower dental arch casts were measured and processed for occlusal contact image creation using both devices. The graphical images of the occlusal contacts at the intercuspal position obtained from both systems and an occlusal analysis device (BE-1) were compared with the occlusal contact area. Excellent correlation was observed between the measurement results of ARCTICA and FN503 (p<0.001, R2: 0.99). The occlusal contact areas were 186.0 mm2 (ARCTICA), 192.8 mm2 (FN503), and 196.1 mm2 (BE-1). This study showed that ARCTICA is capable of conducting highly accurate measurements and generating a graphical image of occlusal contacts with good reliability.

Measurement of Range of Motion with a Non-Contact Three-Dimensional Measurement Device

Measurement of Range of Motion with a Non-Contact Three-Dimensional Measurement Device

Reliability and measurement error of sagittal spinal motion parameters in 220 patients with chronic low back pain using a three-dimensional measurement device

Background contextA basic premise for any instrument measuring spinal motion is that reliable outcomes can be obtained on a relevant sample under standardized conditions. PurposeThe purpose of this study was to assess the overall reliability and measurement error of regional spinal sagittal plane motion in patients with chronic low back pain (LBP), and then to evaluate the influence of body mass index, examiner, gender, stability of pain, and pain distribution on reliability and measurement error. Study design/settingThis study comprises a test-retest design separated by 7 to 14 days. Patient sampleThe patient cohort consisted of 220 individuals with chronic LBP. Outcome measuresKinematics of the lumbar spine were sampled during standardized spinal extension-flexion testing using a 6-df instrumented spatial linkage system. MethodsTest-retest reliability and measurement error were evaluated using interclass correlation coefficients (ICC1,1) and Bland-Altman limits of agreement (LOAs). ResultsThe overall test-retest reliability (ICC1,1) for various motion parameters ranged from 0.51 to 0.70, and relatively wide LOAs were observed for all parameters. Reliability measures in patient subgroups (ICC1,1) ranged between 0.34 and 0.77. In general, greater (ICC1,1) coefficients and smaller LOAs were found in subgroups with patients examined by the same examiner, patients with a stable pain level, patients with a body mass index less than below 30 kg/m2, patients who were men, and patients in the Quebec Task Force classifications Group 1. ConclusionsThis study shows that sagittal plane kinematic data from patients with chronic LBP may be sufficiently reliable in measurements of groups of patients. However, because of the large LOAs, this test procedure appears unusable at the individual patient level. Furthermore, reliability and measurement error varies substantially among subgroups of patients.

Handheld Three-Dimensional Thermo-Sensing System

Recently, three-dimensional (3D) measurement technology has achieved a high level of satisfaction in various fields such as medical and engineering fields. However, most of three-dimensional measurement systems have some disadvantages. Once the geometric configuration of the system has been determined, the configuration must be maintained until the measurements have been completed. Another disadvantage is the existence of immeasurable area that inherently exists in a single image taken from a fixed angle. In this paper, a handheld three-dimensional thermo-sensing measurement system is presented. This system is composed of a three-dimensional measurement device and a thermographic device. To realize the handy scanning measurement, 3D magnetic sensor is attached on the image capturing devices. Since the movement of the image capturing devices is detected in real-time by the magnetic sensor, the immeasurable area can be reduced by free movement of the image capturing devices. On the basis of the presented mathematical model, this system is possible to detect not only the three-dimensional shape but also the temperature distribution of an object. Experimental results show the feasibility of the measurement system.

C12 MRIを利用した靴のフィット性評価(感性工学II)

It is important to evaluate the performance of shoes functions, including fitting, shock-absorbing, and stability. Especially, shoe fitting is one of the most significant factors because it profoundly influences other factors. In previous studies, after each shape of feet and shoes was measured separately by using three-dimensional measurement device, these data were superimposed in computer and shoe fitting was evaluated in virtual space and thus the deformation of feet when wearing shoes was not taken into consideration. To solve this problem, we investigated shoe fitting by using MRI to take feet images when wearing shoes and constructed three-dimensional foot models. We could observe the deformation of feet when wearing shoes by using MRI, and there was relationship between the deformation of feet and results of sensory test for shoe fitting when wearing shoes.

The development of the three-dimensional measurement device in an input device for people of quadriplegia

The development of the three-dimensional measurement device in an input device for people of quadriplegia

인공지능형 삼차원 Foot Scanning 시스템에 관한 연구

In this paper, for manufacturing a custom-made shoes, shape of foot acquired three-dimensional measurement device which makes shoe-last data for needing a custom-made shoes is founded on artificial intelligence technique and it shows method restoring to the original shape in optimized state. the developed system for this study is based on PC which uses existing three dimensional measurement method. And it gains shoe-last and data of foot shape going through 8 CCD(Charge Coupled Device) Which equipped top and bottom, right and left sides and 4 lasers which also equipped both sides and upper and lower sides. The acquired data are processed image processing algorithm using artificial intelligence technique. And result of data management is better quality of removing noise than other system not using artificial intelligence technique and it can simplify post-processing. So, this paper is constituted hardware and software system and it used neural network for determining threshold value, when input image on pre-processing step is being stage of image binarization and present that results.

Three-Dimensional Measurement with a Scanning Parallel Laser Beam.

A demand for non-contact measurements in processes is increasing, especially for threedimensionalmeasuerment. The three-dimensional measurement device based on laser trigonometryusing a scanning parallel beam has been developed. The device is capable of measuringthe shape of an object at high speeds, because the output voltage is proportional to themeasured shape. A measurement device with two cylindrical lenses as a focusing lens has alsobeen made. It is suitable for measurement of the shape of a wide and thin object like a plate. The measurement error is found to be below ±40 μm.