Handheld 3D Scanner Research Articles

Development of Handheld 3D Scanner using RGB-D Sensor

Development of Handheld 3D Scanner using RGB-D Sensor

An International, Multicenter Field Trial Comparison Between 3D-Printed and ICRC-Manufactured Transtibial Prosthetic Devices in Low-Income Countries

ABSTRACT Introduction The gap between the needs of individuals with amputation and access to prosthetists in low-income countries (LICs) is significant. Training new personnel to bridge this gap would exceed the current output of all prosthetic and orthotic programs globally. Strategies are needed to increase the productivity of existing prosthetists in order to serve more patients. Emerging technologies such as 3D scanning, modeling, and printing have been investigated for their ability to decrease the manufacturing time for prosthetic devices; however, few studies have compared the efficacy of 3D-printed devices to traditionally manufactured (e.g., International Committee of the Red Cross [ICRC]) devices. Studies that previously compared these two methods were limited by low population size and restricted timeframes. The purpose of this study was to gather evidence comparing the efficacy of 3D-printed and ICRC transtibial prostheses in large patient populations in LICs over time. Materials and Methods A total of 61participants between the ages of 5 and 25 completed this study's 8-week trial. Participants were recruited from four clinical sites in Uganda, Tanzania, and Cambodia. Ethics approval was obtained from each of the four clinical sites before study initiation. Consent was obtained from each participant before study enrolment. The participants' residual limbs were 3D scanned by local prosthetists using hand-held 3D scanners. Prosthetists digitally rectified the 3D scanned models using Canfit and NiaFit 3D modeling software. The rectified models were fabricated using 3D printers. 3D-printed devices were lined with foam liners and coupled to standard ICRC pylons and feet. Participants used the 3D-printed sockets for 4 weeks, then returned to the clinic to complete a 28-question Likert scale questionnaire, assessing their experiences with their 3D-printed devices. Surveys were based on the Prosthesis Evaluation Questionnaire. Participants were then given a new transtibial prosthetic device manufactured using traditional ICRC methods and instructed to use this device for 4 weeks. They then returned to the clinic to complete the questionnaire as aforementioned. Responses from both surveys were assessed using a two-tailed Student t-test (P < 0.05). Results Data from the Tanzania Training Centre for Orthopaedic Technologists (n = 10) indicated that their users rated ICRC devices significantly higher in categories measuring stability, including ability to walk, walking up steep slopes and stairs, walking on slippery surfaces, overall fit, comfort while standing, and texture of the device. In contrast, participant data from Comprehensive Rehabilitation Services in Uganda (n = 25), Cambodian School of Prosthetics and Orthotics (n = 10), and Comprehensive Community Based Rehabilitation in Tanzania (n = 16) showed no significant differences across all measured outcomes. Conclusions This is the first study to compare and contrast the efficacy of 3D-printed and ICRC transtibial prosthetic devices across geographic locations in LICs with a large study population. Results demonstrate that, in general, 3D-printed devices were rated comparably to ICRC. This result was consistent at three of four clinical trial sites. Further studies will be required to elucidate the rating differences observed at the fourth site.

Low Cost Handheld 3D Scanning for Egyptian Architectural Artifacts Acquisition

Surface reconstruction of objects using photogrammetry and terrestrial laser scanning systems (TLS) has been a topic for research for many decades, especially for culture heritage data recording. Recently, many advances into these systems are now available in the market, which give the availability of collecting a huge number of geo-referenced 3-D points covering any object surface. Due to speed and efficiency of data acquisition by means of terrestrial laser scanners, researchers and designers can select the reliable technique, depending on their application, that can be complete to give good results for the complex surfaces such as heritage objects. As Grand Egyptian Museum (GEM), located nearby the Giza Pyramids, is set to open by 2020, which considered as the largest museum from its type all over the world, with a huge area covered about a half million m2. GEM is proposed to be a unique museum all over the world for presenting a huge number from old history Egyptian artifacts. Consequently, there is a vital need for building a huge digital database containing complete information for this large number of artifacts. Mobile applications are presently at the primacy of documenting historical and archaeological sites. The current paper examine the methodological framework adopted for one high copy of Pharaonic artifacts, namely Offering Carrier, using hand held laser scanning and convert the results to a mobile application.

Validating 3D indexes in the non-surgical pectus excavatum patient

Background/purposeIn recent years there has been an increased interest in three-dimensional (3D) imaging for the assessment of chest wall deformities. Some studies have proven a correlation between 3D and traditional cross-sectional images but only for patients who already had an indication for a computed tomography (CT) scan prior to surgery; mainly due to their severity. Our aim is to determine the accuracy and reliability of the measures obtained by a portable 3D scanner in a cohort of pectus excavatum (PE) patients with different severity grades, as well as in controls. MethodsWe conducted a study comparing radiological and optical indexes on magnetic resonance imaging (MRI) and 3D surface images. We used a hand-held 3D scanner to obtain the optical Haller Index (3DHI) and Correction Index (3DCI) and a limited MRI scan to obtain the traditional indexes. A statistical analysis was carried out to determine the correlation between optical and radiological measures, plus a subjective severity evaluation. ResultsTwenty-eight patients and controls were enrolled in the study. In both the control and PE groups, there was a significant positive correlation between the indexes, especially for the CI. There were no differences in correlation regarding gender, age or severity. CI appears to better discriminate amongst the different severity groups and controls. Conclusion3D surface imaging is feasible and appropriate to use to assess PE, regardless of the severity or characteristics of the individual patient. Even with a small hand-held device, we can obtain accurate images and measures which are especially useful for the assessment of the nonsurgical pectus patient.

Improving Lives in Three Dimensions: The Feasibility of 3D Printing for Creating Personalized Medical Aids in a Rural Area of Sierra Leone.

The aim of this feasibility study was to investigate how a 3D printer could be put to its best use in a resource-limited healthcare setting. We have examined whether a 3D printer can contribute to making prostheses, braces, or splints for patients who underwent major limb amputation because of complex wounds, for example, due to burns and subsequent scarring, accidents, conflicts, or congenital abnormalities. During a 3-month period, we investigated the benefits of customized, 3D-printed arm prostheses, splints, and braces in Sierra Leone. Using a handheld 3D scanner and a 3D printer, patient-specific medical aids were designed, manufactured, and tested. Questionnaires regarding patient satisfaction and the functionality of the prostheses were used for a short-term follow-up. Four esthetic prostheses were designed: two prostheses of the hand, one of the forearm, and one of the entire arm. Follow-ups were conducted after 3 to 4 weeks to investigate the quality of the prostheses and to complete a patient questionnaire. Even though the prostheses primarily fulfill esthetic needs, they also exhibit some degree of functionality. In addition, four splints for hands and arms were made to prevent scar contractures after skin transplantation. Finally, a brace for a young boy with kyphoscoliosis was manufactured. The boy has accepted the brace and will be followed up in the months to come. Long-term follow-up is required to prove the sustainability of the 3D-printed brace and prosthetic arms. Further research into how to sustain and refine this project is underway.

Ex vivo experimental and numerical study of stresses distribution in human cadaveric tibiae

The mechanical behaviour of human bone tissue subject to drilling has been recently reviewed due to its increased clinical interest. However, no published data exist regarding stress analysis during the drilling. In this study, an elasto-plastic dynamic FE model of bone drilling was developed using the human cadaveric tibia obtained with a handheld 3D scanner. The FE model was validated with experimental tests and different drilling conditions were simulated in order to study the stresses distribution during the drilling process. The developed FE model was in good agreement when compared with experimental tests. Results suggest that the use of lower drill speed and higher feed-rate lead to a decrease in the stress level of the treated tibial bone. The developed FE model can be used for future studies and cover not only the mechanical behaviour of human tibiae but also the thermal aspects.

Handheld 3D scanning as a minimally invasive measuring technique for neonatal anthropometry

Measurement of length and head circumference (HC) in addition to weight is vital in assessing the nutritional status of preterm infants. Current anthropometry represents an interruption to preterm infants, and may not be possible in unstable infants. Handheld 3D scanning has the potential to perform bedside anthropometry (length and HC) in a less invasive manner. We aimed to evaluate the feasibility and performance of 3D scanning as a 'non-touch' measuring technique for routine anthropometry. Preterm infants born before 30 weeks gestation were recruited from a single neonatal unit. HC and length were measured both manually and by a handheld 3D scanner at recruitment and weekly until discharge. The two methods were compared using the Bland-Altman method and linear regression. Seventeen infants had manual and 3D-scan measurements (67 HC, 87 length). The mean difference (95%CI) between manual and 3D-scan measures, as a percentage of the manual value, was 2.87% (2.27-3.47%) for HC and 3.10% (2.65-3.54%) for length. Correlation between manual and 3D measures was high; HC r=0.957 and length 0.963. Bland-Altman plots showed reasonable agreement between the two methods, and there was a high correlation between scanner and manual measurements. These data show a high correlation between measurements gathered from 3D scan images and standard anthropometry. However, 3D measures are not yet precise enough for routine clinical use. Refinement of technique/technology may translate into practical monitoring the growth of preterm infants with minimal handling and without interruption to developmental care.

Application of 3D scanning and 3D printing for designing and fabricating customized half-mask facepieces: A pilot study.

The main function of respiratory protective devices is to provide an intact physical barrier between the environment and the user. To ensure that, a leak-tight fit of the facepiece to the user's face is essential, regardless of the user's individual facial features. The main objective of this study was to assess the possibilities of developing customized respirators well-fitting to the anthropometric dimensions of the user's face using 3D scanning and 3D printing techniques and to evaluate this custom-made device in terms of protective, usage and strength parameters. Commercially available twin-filter half-mask type MP22/2 was selected as base model for customization. The 3D scans of the half-mask facepiece were performed using ATOS Core optical 3D scanner. Simultaneously anthropometric measurements of the test subject face were carried out with hand-held 3D scanner Artec EVA. Then digital model of the facepiece was matched to the shape of user's face using Geomagic Touch X haptic device. Customized facepieces were printed out with use of selective laser sintering technique from thermoplastic polyurethane. After assembling, respirators were tested for compliance with the requirements of the European standards. The developed respirators proved to be very well-fitted to the user's face, did not cause any imprints or skin irritations and were assessed positively in terms of protective, usage and strength parameters. The application of 3D scanning and 3D printing techniques for designing and fabricating customized half-mask facepieces constitutes a viable option for the future development of respiratory protective devices.

3D 스캔데이터를 활용한 동작별 하반신 너비ᆞ두께 변화 비교 연구 : 20~24세 여성을 중심으로

The purpose of this study is to identify the changes in the breadth and depth measurements of women’s lower bodies with different postures, walking, stair climbing and chair sitting, to improve manufacturers’ understanding to the extent where such information should be considered when developing pants patterns with better fit and function. Lower body scan data of 13 women aged between 20-24 years were collected using a hand-held 3D scanner, Artec Eva, and digitally manipulated in preparation for breadth and depth measurements using commercially available software, Meshlab. The measurements were then statistically analyzed through SPSS 21.0 to obtain the average amounts and rates of extension and contraction for each measurement item. The results from this study demonstrated that the amount of change in the breadths and depths of the lower body differs depending on the size and range of postures, and thus the largest extension and contraction occurred in the measurements around the joints; front knee depth and knee breadth. Factor analysis confirmed these results. Factors 1 and 3, which involve knee-related measurement items, identified meaningful differences, especially in chair sitting posture, where larger joint movements are required. Therefore, the findings of this study can be applied to making key decisions in the manufacturing process, such as selecting fabrics and allowing ease values, that are likely to influence the level of fit and comfort of the pants.

3D Scanning in Repairing Tractor and Automobile Parts and Units

The authors have found that the expenditures in the structure of the production cost of repairing machines depend not only on the cost of spare parts and materials, but also on the assessment accuracy of the technical condition of inspected parts. Research purpose To study the possibilities of 3D scanning technology, to improve the measuring accuracy of worn parts during fault finding, and to determine a rational way to restore them. Materials and methods The authors have carried out the entrance control using the Artec Eva Lite portable handheld 3D scanner with the Artec Studio software while finding faults in the worn crankshaft of the Z М Z­409 engine. They have used the Geomagic Control X software product, which allows carrying out three­dimensional analysis of the part and obtain high­precision measurements, determine the wear of mutual rubbing surfaces, the presence of microcracks, damage to internal cavities and dents in complex­shaped parts. Basing on the conventional technology and reference recommendations, they plotted the route of the crankshaft restoration technology. Results and discussion The authors have compared the measurement results obtained using metrology instruments and reports in the Geomagic Control X program. They have found significant differences, especially in the amount of digital data. It has been determined that the measurement accuracy obtained from the instruments turned out to be lower. Worn connecting rods and main journals of the Z М Z­409 engine crankshaft have been restored by electrocontact welding of filler materials according to the recommended application modes. Conclusions The research has revealed the possibility of using 3D­scan in the process of repair and restoration. The authors have proved that this method allows increasing the efficiency of fault finding, shorten its duration in 6 times, reduce the level of subjectivity of the technical condition assessment of inspected parts and reduce the complexity of the process by 30 percent. The authors have confirmed the high accuracy of measurements (up to 0.03 millimeters), owing to which the direct costs of filler materials can be reduced by 20 percent. On the basis of the 3D scanning results, the authors have proposed to form databases in the form of digital archives of parts by groups and brands for subsequent operational use.

Comparison of different body measurement techniques: 3D stationary scanner, 3D handheld scanner, and tape measurement

Body measurements play an import role in pattern generation and size determination. Traditionally, body measurements were captured with tape measures. The tape measure technique is often time-consuming. Nowadays, three-dimensional (3D) stationary whole-body scanners are widely used in the apparel industry to collect body measurements. The stationary scanner has good performance on efficiency, validity, and reliability. However, it is not suitable for home use due to its high cost. Occipital’s Structure Sensor, as a representation for low-price handheld 3D scanners, is a 3D scanner for mobile devices. This research focused on studying whether the Structure Sensor could be used to capture body measurements for the apparel industry or not. Its performance was compared to a whole-body stationary scanner and the tape measurement. It was found that the Structure Sensor could be used to collect body measurements data with relatively low reliability if corresponding measurement extraction software was developed.

Soil surface roughness decay under different topographic conditions

Soil surface roughness (RR) is one of the most significant factors influencing hydrological and erosion processes. It is most likely affected by topographic conditions, but this relationship has not been quantified. This study was conducted to detect the effects of topographic conditions on soil surface roughness decay after tillage and to determine the dominant mechanism affecting RR on the Loess Plateau. From June 10 to October 3, 2017, RR was measured using a handheld 3D scanner in six plots with different slope gradients and at three different slope positions along a 60 m plot. The results showed that soil surface roughness was significantly affected by slope gradient and position. RR increased exponentially with an increase in slope gradient (R2 = 0.97). The middle slope position exhibited the maximum RR, whereas the downslope position exhibited the minimum RR. Soil surface roughness decreased exponentially over time after tillage under different topographic conditions ranging from 0.91 to 4.50 mm. For the six plots with different slope gradients, rapid decreases in RR occurred from July 24 to Sept. 10, but for the three different slope positions, rapid decreases occurred from June 10 to July 24. RR declined exponentially with an increase in cumulative rainfall (266.4 mm, R2 = 0.88) and kinetic energy (38.9 MJ ha−1, R2 = 0.92). Cumulative kinetic energy was a better predictor of RR decay than cumulative rainfall at different slope positions. However, for plots with different slope gradients, RR decay after tillage was best estimated by slope gradient and cumulative rainfall (NSE = 0.95) or kinetic energy (NSE = 0.96). After tillage, the soil bulk density, crust thickness and soil cohesion increased significantly over time under different topographic conditions. RR decreased linearly with increasing bulk density, crust thickness, and cohesion. The breakdown of aggregates or clods was the dominant process leading to soil surface roughness decay in this study.

Method for measuring wear on boot outsoles using a 3D laser scanner

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.

Application of Handheld 3D Scanner in Quantitative Study of Slope Soil Erosion

Simulated rainfall experiment on loess slope. By using Artec Eva handheld three-dimensional (3D) scanner to carry out high-precision scanning of loess slope runoff plots before and after each rainfall, quantitative analysis of slope soil erosion. The results show that using the handheld 3D scanner to scan the slope before and after rainfall, the calculated error of soil erosion is small. The calculated errors of 7 times were -1.428%, 2.843%, -3.189%, 1.141%, -0.945%, -3.240% and 1.287%, respectively. The calculated errors were within ± 4%. Using this scanner, the distribution of slope erosion can be observed very intuitively, and the slope erosion volume and soil erosion amount can be calculated quickly and accurately.

COMPARATIVE GEOMETRICAL ACCURACY INVESTIGATIONS OF HAND-HELD 3D SCANNING SYSTEMS – AN UPDATE

Abstract. Hand-held 3D scanning systems are increasingly available on the market from several system manufacturers. These systems are deployed for 3D recording of objects with different size in diverse applications, such as industrial reverse engineering, and documentation of museum exhibits etc. Typical measurement distances range from 0.5 m to 4.5 m. Although they are often easy-to-use, the geometric performance of these systems, especially the precision and accuracy, are not well known to many users. First geometrical investigations of a variety of diverse hand-held 3D scanning systems were already carried out by the Photogrammetry & Laser Scanning Lab of the HafenCity University Hamburg (HCU Hamburg) in cooperation with two other universities in 2016. To obtain more information about the accuracy behaviour of the latest generation of hand-held 3D scanning systems, HCU Hamburg conducted further comparative geometrical investigations using structured light systems with speckle pattern (Artec Spider, Mantis Vision PocketScan 3D, Mantis Vision F5-SR, Mantis Vision F5-B, and Mantis Vision F6), and photogrammetric systems (Creaform HandySCAN 700 and Shining FreeScan X7). In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data was acquired by measurements with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

Correction: Measurements agreement between low-cost and high-level handheld 3D scanners to scan the knee for designing a 3D printed knee brace.

[This corrects the article DOI: 10.1371/journal.pone.0190585.].

Research On the Standard Operation Procedure of Mobile 3D Scanner

1. Abstract 1.1. Background: For the past few years, 3D facial imaging technology has been widely used as preoperative evaluation and surgery design for plastic and cosmetic surgery. Compare to the stationary scanner, handheld scanner is more portable and mobile, which leads to a higher demand for the operator manipulation. The aim of this study is to search and improve the standardized procedure of handheld 3D scanner, in order to collect preferable data and improve treatment accuracy. 1.2. Methods: Artec Eva 3D scanner was used to scan the subject head-face area. By altering the distance and angle between the scanner and subject, changing the scanner movement patterns and tracks, and modifying the light and background, multiple images were collected and analysed. By comparing the differences between generated images and the amount of software errors, the best operation procedure for mobile 3D scanner was concluded. 1.3. Results: With adequate light, the optimal distance between scanner and subject (working distance) was 80cm, and the scanner was 5cm above the subject head. The scanner was stabilized on a tripod with wheels and scans following an arc track. The optimal scanning time was 8s, which was easy to control and could keep the integrity of collected images at the same time. 1.4. Conclusion: By the comparative study of light, background, distance, angle and scanner movement pattern, we found that handheld scanner with standardized operation procedure can stable the scanning results and improve the collection efficiency and accuracy. 2. Keywords: Accurate Treatment Method; Facial Scanning; Mobile 3D Scanner; Standardized Operation

Measurements agreement between low-cost and high-level handheld 3D scanners to scan the knee for designing a 3D printed knee brace.

Use of additive manufacturing is growing rapidly in the orthotics field. This technology allows orthotics to be designed directly on digital scans of limbs. However, little information is available about scanners and 3D scans. The aim of this study is to look at the agreement between manual measurements, high-level and low-cost handheld 3D scanners. We took two manual measurements and three 3D scans with each scanner from 14 lower limbs. The lower limbs were divided into 17 sections of 30mm each from 180mm above the mid-patella to 300mm below. Time to record and to process the three 3D scans for scanners methods were compared with Student t-test while Bland-Altman plots were used to study agreement between circumferences of each section from the three methods. The record time was 97s shorter with high-level scanner than with the low-cost (p = .02) while the process time was nine times quicker with the low-cost scanner (p < .01). An overestimation of 2.5mm was found in high-level scanner compared to manual measurement, but with a better repeatability between measurements. The low-cost scanner tended to overestimate the circumferences from 0.1% to 1.5%, overestimation being greater for smaller circumferences. In conclusion, 3D scanners provide more information about the shape of the lower limb, but the reliability depends on the 3D scanner and the size of the scanned segment. Low-cost scanners could be useful for clinicians because of the simple and fast process, but attention should be focused on accuracy, which depends on the scanned body segment.

Experimental investigation on cohesionless sandy bank failure resulting from water level rising

In the last decade, sediment replenishment forming cohesionless sandy banks below dams has become an increasingly common practice in Japan to compensate for sediment deficits downstream. The erosion process of the placed cohesionless sediment is a combination of lateral toe-erosion and the following mass failure. To explore cohesionless bank failure mechanisms, a series of experiments was done in a soil tank using a compacted sandy soil mass exposed to an increasing water level. Two types of uniform sand (D50 = 0.40mm and 0.17mm) and two bank heights (50cm and 25cm) were used under the condition of a constant bank slope of 75°. The three dimensional (3D) geometry of the bank after failure was measured using a handheld 3D scanner. The motion of bank failure was captured using the particle image velocimetry (PIV) technique, and the matric suction was measured by tensiometers. The compacted sandy soil was eroded by loss of matric suction accompanying the rise in water level which subsequently caused rotational slide and cantilever toppling failure due to destabilization of the bank. The effect of erosion protection resulting from the slumped blocks after these failures is discussed in the light of different failure mechanisms. Tensile strength is analyzed by inverse calculation of cantilever toppling failure events. The tensile strength had non-linear relation with degree of saturation and showed a peak. The findings of the study show that it is important to incorporate the non-linear relation of tensile strength into stability analysis of cantilever toppling failure and prediction of tension crack depth within unsaturated cohesionless banks.

PERFORMANCE INVESTIGATION OF A HANDHELD 3D SCANNER TO DEFINE GOOD PRACTICES FOR SMALL ARTEFACT 3D MODELING

Abstract. Handheld 3D scanners can be used to complete large scale models with the acquisition of occluded areas or small artefacts. This may be of interest for digitization projects in the field of Cultural Heritage, where detailed areas may require a specific treatment. Such sensors present the advantage of being easily portable in the field, and easily usable even without particular knowledge. In this paper, the Freestyle3D handheld scanner launched on the market in 2015 by FARO is investigated. Different experiments are described, covering various topics such as the influence of range or color on the measurements, but also the precision achieved for geometrical primitive digitization. These laboratory experiments are completed by acquisitions performed on engraved and sculpted stone blocks. This practical case study is useful to investigate which acquisition protocol seems to be the more adapted and leads to precise results. The produced point clouds will be compared to photogrammetric surveys for the purpose of their accuracy assessment.