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The present work is focused on the direct manufacturing of a hand splint using free-open access software and a low-cost three-dimensional printer (3DP). The hand digital model was created using panoramic photos by a common mobile phone camera. The photos were used as input to the "3DF-Zephyr" free software for creating the hand surface model. Then,...
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Context 1
... was "thicken" to give the required thickness. Then, after the splint took the shape of the hand, its buttons were designed, which are circular in the form of a groove, so that they can be closed using a washer. In order to facilitate the installation and the removal of the washer, recesses were designed that allow the placement of the finger (Fig. 2). The dimensions of the buttons are: Splint length: 13.78 cm; Splint thickness: ≈ 5mm; Button diameter: 20mm (outer) -15mm (inner); Slot thickness: 5mm; Slot depth: 3.5mm; Diameter for finger on the clasp (Depth: 3mm, Tolerance: ± 0.3mm, the lowest point in oval shape). The number of buttons designed is four. Their location was chosen ...
Context 2
... was "thicken" to give the required thickness. Then, after the splint took the shape of the hand, its buttons were designed, which are circular in the form of a groove, so that they can be closed using a washer. In order to facilitate the installation and the removal of the washer, recesses were designed that allow the placement of the finger (Fig. 2). The dimensions of the buttons are: Splint length: 13.78 cm; Splint thickness: ≈ 5mm; Button diameter: 20mm (outer) -15mm (inner); Slot thickness: 5mm; Slot depth: 3.5mm; Diameter for finger on the clasp (Depth: 3mm, Tolerance: ± 0.3mm, the lowest point in oval shape). The number of buttons designed is four. Their location was chosen ...
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Citations
... When the cross-sectional area of the strand is reduced, i.e. the height or width is reduced, the total planar contact/bonding area between the strands increases. [36,37] Increasing or decreasing the contact area affects the mean diameter and number of pores, resulting in different types of porosity and fracture mechanisms. Note here that the temperature and feed speed also significantly interact with the strand cross-section voids' mean diameter and aspect ratio. ...
The filament material extrusion (ME) process manufactures functional components for a wide range of personalized applications in medicine, fashion and remanufacturing cases, or customized batch production for aviation and automotive industries. Therefore, structural and welding parameters affect porosity during 3D printing and are of paramount interest concerning the parts’ mechanical response to static and dynamic loadings. This work aims to arrange the literature’s experimental findings of crucial processing parameters’ effects on the fused filament fabrication (FFF) part’s porosity and structural strength. Therefore, the materials and structure parameters, including the filament material properties, deposited strand geometry, infill rate, infill pattern design type and orientation, and part orientation, as well as welding parameters such as material flow, nozzle temperature, bed temperature, printing feed, and environmental conditions, are critically reviewed and study in profoundness regarding porosity and mechanical loading of 3D printed parts. Experimental studies are critically examined, emphasizing the effects of parameters and interactions between them.
... This study aims to address this issue by using FDM printing [13] to make a durable and comfortable wrist brace for the purpose of extending the tendons of severely burned patients during rehabilitation in order to increase their range of motion (ROM) [2,14]. Most importantly, this layout keeps the patient's functional use of their hand unaffected by the healing and rehabilitative processes [15,16]. ...
Severe and common injuries involving burns to the hands and wrists can often lead to permanent loss of motion. The issue is exacerbated by the delicate nature of tendons and muscles in the hands, along with the formation of scar tissue. While rehabilitation exercises can help improve the range of motion, early-stage recovery requires additional tension on the affected areas. To address this concern, a novel project was initiated, aiming to develop a specialized splint for later-stage rehabilitation. This innovative splint allows users to carry out their daily tasks while wearing it, constantly applying a beneficial load on the wrist, hand, and digits to enhance range of motion. The development of the splint involved leveraging Fused Deposition Modelling (FDM) 3D printing and medically safe materials for the initial prototype. Finite Element Analysis (FEA) was employed to analyze the design. The process underwent iterative design improvements and parameter adjustments, ultimately resulting in the final prototype. The FEA analysis confirmed the strength and durability of the PLA components, while the TPU digit resistance bands were evaluated using a hyper-elastic model. As a result, the final design effectively applies tension to the digits without compromising day-to-day tasks’ usability and wearer’s comfort. Future iterations of the splint could focus on enhancing fastening methods, reducing brace movement during usage, creating various sizes to accommodate different arm/hand dimensions, and optimizing mass-manufacturing processes.
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In order to solve the problems of the traditional 3D simulation system of indoor soft decoration, such as the lack of effective enrichment, rendering means, and poor authenticity when selecting the geometric modeling method to simulate the effect of indoor soft decoration, this paper proposes a 3D simulation system of indoor soft decoration based on OpenGL and Direct3D. The system uses 3DMAX software to establish the indoor model, imports the model into the OpenGL 3D graphics standard library module, draws the indoor soft decoration scene elements using the basic geometric elements, and constrains the scene elements through the wall, overlap, and size constraint functions, so as to ensure the reasonable layout of the indoor soft decoration agent area and enrich the indoor model. After enrichment, the indoor model is transmitted to the Direct3D rendering engine module transformation unit to implement the soft decoration layout, and the lighting unit and rasterization unit are used to render the indoor after layout so as to obtain the optimal indoor soft decoration effect and output the 3D simulation image of indoor soft decoration. The experimental results show that the favorability, operation sensitivity, design portability, design satisfaction, and soft fitting effect score of the system are higher than those of the Untiy3D system and Smart3D system. The average score of this system is about 95, while the average score of the Untiy3D system is lower than 89, and the average score of the Smart3D system is lower than 85. Conclusion. The three-dimensional simulation effect of indoor soft decoration of this system is good, the design is convenient, the operation is sensitive, and the user satisfaction is high, which provides a reliable analysis basis for indoor design.
... The researchers have studied the strength characteristics of FFF parts for over two decades [1,[13][14][15][16]. Part orientation (PO) inside the build space and the deposition parameters affect the interlaminar strength between the deposited material [17,18] and, consequently, the FFF parts' mechanical response and surface quality [19][20][21][22][23][24]. The raster Deposition Angle (DA) also affects the tensile stress of polylactic acid (PLA) FFF parts; 0° raster DA results in higher tensile stress than 45° and 90° [25]. ...
This study investigates the effects of four variables during fused filament fabrication of organic biocompatible composite material, PLA with coconut flour, at the ultimate tensile strength (UTS), and elasticity module (E) of the printed parts. The parameter optimization uses Taguchi L18 design and regression models. The examined deposition variables are the layer thickness, the nozzle temperature, the raster deposition angle, and filament printing speed. The effects of the above variables on the strength of the parts are essential to enhance the mechanical response of the printed parts. The experimental outcomes are investigated using the ANOM and ANOVA and modeled utilizing linear regression models. In addition, an independent experiment was repeated three times at optimum parameters’ levels to evaluate the methodology, giving predictions errors less than 3%. The observed results showed that the raster deposition angle dominates among the other variables in the studied experimental area.
... [9][10][11] This technology's main benefits are a shorter cycle-time and reduced costs than conventional manufacturing processes. [12][13][14] Furthermore, the usefulness of AM is confirmed when the produced item is becoming more and more complex. [15] Therefore, AM can benefit consumers, automotive and aerospace, and bioengineering industries. ...
Fused filament fabrication (FFF) is an additive manufacturing process, which constructs physical items by fused melt material, selectively deposited layer-by-layer through a heated extrusion mechanism. Parameters’ selection and control in FFF are of utmost importance since they significantly affect the surface quality (SQ) and dimensional accuracy (DA) of the FFF printed parts. In the present paper, initially, the FFF process is briefly presented. Next, a cause-and-effect diagram exhibits the process parameters’ categorization with the SQ and DA of the manufactured parts. Then, according to the robust design theory, the process parameters are divided into three classes, i.e., the signal, the control, and the noise. This classification supports the selection of appropriate FFF printers, according to the control parameters, whereas it facilitates the optimization of the SQ and DA of printed parts, concerning the signal parameters. Finally, the impact of each parameter on SQ and DA is presented, supported by an extensive literature review. Overall, the process parameters’ optimization is critical for the SQ and DA. Therefore, they should be adjusted to achieve higher quality and less post-processing work.
Introducing Additive Manufacturing (AM) techniques for orthopedic orthosis fabrication is a significant help in treating of patients with fractured wrists. In particular, customized orthosis fabricated by Fused Deposition Modeling (FDM) can provide best patient comfort with reduced incidence of various complications due to air permeability. The research objective of this paper is to determine reasonable structural dimension for reducing unnecessary material consumption while ensuring strength and safety when fabricating the customized orthopedic orthosis by the FDM technique. This paper presents a reasonable approach to determine structural dimension of the FDM fabricated orthopedic orthosis using Uniform Design (UD), finite element simulation, Simple Additive Weighting (SAW) method, multiple regression analysis, and grid search optimization method. Three-dimensional (3D) models of wrist were reconstructed from computer tomography image data for wrist fracture sites. Nine Computer-Aided Design (CAD) 3D models of the wrist orthosis with different shell thickness, lattice thickness and number of vents were designed using the UD method. The stress analyzes with load conditions in different directions were carried out using the finite element simulation and overall performance scores (simple weighted sums) were calculated using the SAW method at each experimental trial. The reasonable structural dimension of the wrist orthosis was determined using multiple regression model and grid search optimization method. The reasonable structural dimension was shell thickness of 2.2 mm, lattice thickness of 6.4 mm, and number of ventilation holes of 15. The fabricated orthosis with the reasonable structural dimension may improve the treatment effect, satisfaction and comfort for patients with fractured wrists. The proposed approach could be actively applied to optimize not only the structural dimension of FDM fabricated orthosis but also FDM process parameters.
The additive manufacturing technique of material extrusion has challenge of excessive process defects and not achieving the desired mechanical properties. The industry is trying to develop certification to better control variations in mechanical attributes. The current study is a progress towards understanding the evolution of processing defects and the correlation of mechanical behavior with the process parameters. Modeling of the 3D printing process parameters such as layer thickness, printing speed, and printing temperature is carried out through L27 orthogonal array using Taguchi approach. In addition, CRITIC embedded WASPAS is adopted to optimize the parts' mechanical attributes and overcome the defects. Flexural and tensile poly-lactic acid specimens are printed according to ASTM standards D790 and D638, respectively, and thoroughly analyzed based on the surface morphological analysis to characterize defects. The parametric significance analysis is carried out to explore process science where the layer thickness, print speed, and temperature significantly control the quality and strength of the parts. Mathematical optimization results based on composite desirability show that layer thickness of 0.1 mm, printing speed of 60 mm/s, and printing temperature of 200 °C produce significantly desirable results. The validation experiments yielded the maximum flexural strength of 78.52 MPa, the maximum ultimate tensile strength of 45.52 MPa, and maximum impact strength of 6.21 kJ/m². It is established that multiple fused layers restricted the propagation of cracks with minimum thickness due to enhanced diffusion between the layers.
