scholarly journals Detection and Identification of Defects in 3D-Printed Dielectric Structures via Thermographic Inspection and Deep Neural Networks

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4168
Author(s):  
Barbara Szymanik ◽  
Grzegorz Psuj ◽  
Maryam Hashemi ◽  
Przemyslaw Lopato
Keyword(s):  
Temperature Difference ◽  
Signal Analysis ◽  
Acrylonitrile Butadiene Styrene ◽  
External Energy ◽  
3D Print ◽  
Temporal Representation ◽  
Detection And Identification ◽  
External Energy Source ◽  
3D Printed ◽  
Dielectric Structures

In this paper, we propose a new method based on active infrared thermography (IRT) applied to assess the state of 3D-printed structures. The technique utilized here—active IRT—assumes the use of an external energy source to heat the tested material and to create a temperature difference between undamaged and defective areas, and this temperature difference is possible to observe with a thermal imaging camera. In the case of materials with a low value of thermal conductivity, such as the acrylonitrile butadiene styrene (ABS) plastic printout tested in the presented work, the obtained temperature differences are hardly measurable. Hence, the proposed novel IRT method is complemented by a dedicated algorithm for signal analysis and a multi-label classifier based on a deep convolutional neural network (DCNN). For the initial testing of the presented methodology, a 3D printout made in the shape of a cuboid was prepared. One type of defect was tested—surface breaking holes of various depths and diameters that were produced artificially by inclusion in the printout. As a result of examining the sample via the IRT method, a sequence of thermograms was obtained, which enabled the examination of the temporal representation of temperature variation over the examined region of the material. First, the obtained signals were analysed using a new algorithm to enhance the contrast between the background and the defect areas in the 3D print. In the second step, the DCNN was utilised to identify the chosen defect parameters. The experimental results show the high effectiveness of the proposed hybrid signal analysis method to visualise the inner structure of the sample and to determine the defect and size, including the depth and diameter.

Optimization of 3D Print Material for the Recreation of Patient-Specific Temporal Bone Models

2018 ◽  
Vol 127 (5) ◽  
pp. 338-343 ◽  
Author(s):  
Max Haffner ◽  
Austin Quinn ◽  
Tsung-yen Hsieh ◽  
E. Bradley Strong ◽  
Toby Steele
Keyword(s):  
Temporal Bone ◽  
Haptic Feedback ◽  
Acrylonitrile Butadiene Styrene ◽  
3D Models ◽  
Patient Specific ◽  
3D Print ◽  
Print Material ◽  
Unique Material ◽  
3D Printed ◽  
Study Participants

Objective: Identify the 3D printed material that most accurately recreates the visual, tactile, and kinesthetic properties of human temporal bone Subjects and Methods: Fifteen study participants with an average of 3.6 years of postgraduate training and 56.5 temporal bone (TB) procedures participated. Each participant performed a mastoidectomy on human cadaveric TB and five 3D printed TBs of different materials. After drilling each unique material, participants completed surveys to assess each model’s appearance and physical likeness on a Likert scale from 0 to 10 (0 = poorly representative, 10 = completely life-like). The 3D models were acquired by computed tomography (CT) imaging and segmented using 3D Slicer software. Results: Polyethylene terephthalate (PETG) had the highest average survey response for haptic feedback (HF) and appearance, scoring 8.3 (SD = 1.7) and 7.6 (SD = 1.5), respectively. The remaining plastics scored as follows for HF and appearance: polylactic acid (PLA) averaged 7.4 and 7.6, acrylonitrile butadiene styrene (ABS) 7.1 and 7.2, polycarbonate (PC) 7.4 and 3.9, and nylon 5.6 and 6.7. Conclusion: A PETG 3D printed temporal bone models performed the best for realistic appearance and HF as compared with PLA, ABS, PC, and nylon. The PLA and ABS were reliable alternatives that also performed well with both measures.

The Material Testing of Nanoparticle Doped 3D Printed ABS Strain Gages for Resisitance and Stiffness

2020 ◽  
Author(s):  
Sara M. Damas ◽  
Cameron J. Turner
Keyword(s):  
3D Printing ◽  
Fused Deposition Modeling ◽  
Acrylonitrile Butadiene Styrene ◽  
Strain Gages ◽  
3D Print ◽  
Fused Deposition ◽  
Design And Manufacturing ◽  
Deposition Modeling ◽  
3D Printed ◽  
Conductive Properties

Abstract Additive manufacturing methods are becoming more prominent in the world of design and manufacturing due to their reduction of material waste versus traditional machining methods such as milling. The technology to 3D print has been around since the 1970’s. In today’s present time, we now can multi-material 3D print, however. even though we have the technology for multi-material 3D printing, standards in this field are severely lacking. Research on multi-material 3D printing and/or the combination of 3D printing filaments combined with nanoparticles is needed. One of the most common methods of 3D printing is fused deposition modeling (FDM). In this research, FDM was used to dope Acrylonitrile Butadiene Styrene (ABS), to introduce conductive properties for strain measurements. The researchers in this paper used N-Methyl-2-Pyrrolidinone (NMP) to bind the selected nanoparticles. In the first experiment the researchers tested the conductivity of the strain gages, while in the next experiment they studied the effect the various nanoparticles had on the stiffness of the 3D printed ABS strain gages. This extensive and detailed study concluded several points. First, nickel nanoparticles consistently yields the least amount of resistance. Second, multiple binder doped nanoparticle layers yield the lowest resistance. Third, NMP, does indeed improve the performance of the nanoparticles. Finally, the research demonstrated that the various nanoparticles used, when bound increased the stiffness of the ABS strain gages.

scholarly journals Microstructured Surface Plasmon Resonance Sensor Based on Inkjet 3D Printing Using Photocurable Resins with Tailored Refractive Index

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2518
Author(s):  
Nunzio Cennamo ◽  
Lorena Saitta ◽  
Claudio Tosto ◽  
Francesco Arcadio ◽  
Luigi Zeni ◽  
...  
Keyword(s):  
Surface Plasmon Resonance ◽  
3D Printing ◽  
Surface Plasmon ◽  
Plasmon Resonance ◽  
Optical Sensor ◽  
Low Cost ◽  
3D Print ◽  
Spr Sensor ◽  
Resonance Sensor ◽  
3D Printed

In this work, a novel approach to realize a plasmonic sensor is presented. The proposed optical sensor device is designed, manufactured, and experimentally tested. Two photo-curable resins are used to 3D print a surface plasmon resonance (SPR) sensor. Both numerical and experimental analyses are presented in the paper. The numerical and experimental results confirm that the 3D printed SPR sensor presents performances, in term of figure of merit (FOM), very similar to other SPR sensors made using plastic optical fibers (POFs). For the 3D printed sensor, the measured FOM is 13.6 versus 13.4 for the SPR-POF configuration. The cost analysis shows that the 3D printed SPR sensor can be manufactured at low cost (∼15 €) that is competitive with traditional sensors. The approach presented here allows to realize an innovative SPR sensor showing low-cost, 3D-printing manufacturing free design and the feasibility to be integrated with other optical devices on the same plastic planar support, thus opening undisclosed future for the optical sensor systems.

scholarly journals Essential work of fracture assessment of acrylonitrile butadiene styrene (ABS) processed via fused filament fabrication additive manufacturing

2021 ◽  
Author(s):  
Pawan Verma ◽  
Jabir Ubaid ◽  
Andreas Schiffer ◽  
Atul Jain ◽  
Emilio Martínez-Pañeda ◽  
...  
Keyword(s):  
Acrylonitrile Butadiene Styrene ◽  
Essential Work ◽  
Fused Filament Fabrication ◽  
Essential Work Of Fracture ◽  
Fracture Properties ◽  
Raster Angle ◽  
3D Printed ◽  
Printing Direction ◽  
Work Of Fracture ◽  
Butadiene Styrene

AbstractExperiments and finite element (FE) calculations were performed to study the raster angle–dependent fracture behaviour of acrylonitrile butadiene styrene (ABS) thermoplastic processed via fused filament fabrication (FFF) additive manufacturing (AM). The fracture properties of 3D-printed ABS were characterized based on the concept of essential work of fracture (EWF), utilizing double-edge-notched tension (DENT) specimens considering rectilinear infill patterns with different raster angles (0°, 90° and + 45/− 45°). The measurements showed that the resistance to fracture initiation of 3D-printed ABS specimens is substantially higher for the printing direction perpendicular to the crack plane (0° raster angle) as compared to that of the samples wherein the printing direction is parallel to the crack (90° raster angle), reporting EWF values of 7.24 kJ m−2 and 3.61 kJ m−2, respectively. A relatively high EWF value was also reported for the specimens with + 45/− 45° raster angle (7.40 kJ m−2). Strain field analysis performed via digital image correlation showed that connected plastic zones existed in the ligaments of the DENT specimens prior to the onset of fracture, and this was corroborated by SEM fractography which showed that fracture proceeded by a ductile mechanism involving void growth and coalescence followed by drawing and ductile tearing of fibrils. It was further shown that the raster angle–dependent strength and fracture properties of 3D-printed ABS can be predicted with an acceptable accuracy by a relatively simple FE model considering the anisotropic elasticity and failure properties of FFF specimens. The findings of this study offer guidelines for fracture-resistant design of AM-enabled thermoplastics. Graphical abstract

scholarly journals On the Post-Processing of 3D-Printed ABS Parts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1559
Author(s):  
Mohammad Reza Khosravani ◽  
Jonas Schüürmann ◽  
Filippo Berto ◽  
Tamara Reinicke
Keyword(s):  
Surface Treatment ◽  
Fused Deposition Modeling ◽  
Three Dimensional ◽  
Acrylonitrile Butadiene Styrene ◽  
Experimental Tests ◽  
Fracture Load ◽  
Post Processing ◽  
Fused Deposition ◽  
Dog Bone ◽  
3D Printed

Application of Additive Manufacturing (AM) has significantly increased in the past few years. AM also known as three-dimensional (3D) printing has been currently used in fabrication of prototypes and end-use products. Considering the new applications of additively manufactured components, it is necessary to study structural details of these parts. In the current study, influence of a post-processing on the mechanical properties of 3D-printed parts has been investigated. To this aim, Acrylonitrile Butadiene Styrene (ABS) material was used to produce test coupons based on the Fused Deposition Modeling (FDM) process. More in deep, a device was designed and fabricated to fix imperfection and provide smooth surfaces on the 3D-printed ABS specimens. Later, original and treated specimens were subjected to a series of tensile loads, three-point bending tests, and water absorption tests. The experimental tests indicated fracture load in untreated dog-bone shaped specimen was 2026.1 N which was decreased to 1951.7 N after surface treatment. Moreover, the performed surface treatment was lead and decrease in tensile strength from 29.37 MPa to 26.25 MPa. Comparison of the results confirmed effects of the surface modification on the fracture toughness of the examined semi-circular bending components. Moreover, a 3D laser microscope was used for visual investigation of the specimens. The documented results are beneficial for next designs and optimization of finishing processes.

scholarly journals Does vaporized hydrogen peroxide sterilization affect the geometrical properties of anatomic models and guides 3D printed from computed tomography images?

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Mauricio Toro ◽  
Aura Cardona ◽  
Daniel Restrepo ◽  
Laura Buitrago
Keyword(s):  
Computed Tomography ◽  
Hydrogen Peroxide ◽  
Dimensional Stability ◽  
Acrylonitrile Butadiene Styrene ◽  
Dimensional Error ◽  
Material Extrusion ◽  
Anatomic Models ◽  
3D Printed ◽  
Mean Differences ◽  
Butadiene Styrene

Abstract Background Material extrusion is used to 3D print anatomic models and guides. Sterilization is required if a 3D printed part touches the patient during an intervention. Vaporized Hydrogen Peroxide (VHP) is one method of sterilization. There are four factors to consider when sterilizing an anatomic model or guide: sterility, biocompatibility, mechanical properties, and geometric fidelity. This project focuses on geometric fidelity for material extrusion of one polymer acrylonitrile butadiene styrene (ABS) using VHP. Methods De-identified computed tomography (CT) image data from 16 patients was segmented using Mimics Innovation Suite (Materialise NV, Leuven, Belgium). Eight patients had maxillary and mandibular defects depicted with the anatomic models, and eight had mandibular defects for the anatomic guides. Anatomic models and guides designed from the surfaces of CT scan reconstruction and segementation were 3D printed in medical-grade acrylonitrile butadiene styrene (ABS) material extrusion. The 16 parts underwent low-temperature sterilization with VHP. The dimensional error was estimated after sterilization by comparing scanned images of the 3D printed parts. Results The average of the estimated mean differences between the printed pieces before and after sterilization were − 0,011 ± 0,252 mm (95%CI − 0,011; − 0,010) for the models and 0,003 ± 0,057 mm (95%CI 0,002; 0,003) for the guides. Regarding the dimensional error of the sterilized parts compared to the original design, the estimated mean differences were − 0,082 ± 0,626 mm (95%CI − 0,083; − 0,081) for the models and 0,126 ± 0,205 mm (95%CI 0,126, 0,127) for the guides. Conclusion This project tested and verified dimensional stability, one of the four prerequisites for introducing vaporized hydrogen peroxide into 3D printing of anatomic models and guides; the 3D printed parts maintained dimensional stability after sterilization.

scholarly journals Development of 3D Printed Symbrachydactyly Prosthetic Hand

2019 ◽  
Vol 9 (1) ◽  
pp. 5943-5947
Keyword(s):  
3D Printing ◽  
Minimum Cost ◽  
Acrylonitrile Butadiene Styrene ◽  
Design Stage ◽  
Patient Specific ◽  
Prosthetic Hand ◽  
Simple Task ◽  
3D Printed ◽  
Electrical Component ◽  
Hand Geometry

Symbrachydactyly is a genetical problem occurred to newborn where the newborn experienced underdeveloped or shorten fingers. This condition will limit their normal as even a simple task of holding an item or pushing a button. A device is needed to help them gain a better life. The aim of this project is to fabricate a customized prosthesis hand using 3D printing technology at minimum cost. The proposed prosthetic was not embedded with any electrical component. The patient can only use the wrist to control the prosthetic part which is the prosthetic fingers. The prosthetic hand was also being developed with the patient specific features, which the initial design stage was adapted from a person’s hand geometry using a 3D scanner. Next the model of the prosthesis was analyzed computationally to predict the performance of the product. Different material properties are considered in the analysis to present Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) materials. Then, the prosthesis was fabricated using the 3D printing. The results suggested that PLA material indicated better findings and further be fabricated.

Concept for a gas-cell-driven drug delivery system for therapeutic applications

2011 ◽  
Vol 225 (12) ◽  
pp. 1196-1201 ◽  
Author(s):  
S Becker ◽  
T Xu ◽  
F Ilchmann ◽  
J Eisler ◽  
B Wolf
Keyword(s):  
Energy Source ◽  
Drug Delivery ◽  
Pain Management ◽  
Local Drug Delivery ◽  
Gas Cell ◽  
External Energy ◽  
Micro Pump ◽  
Drug Reservoir ◽  
External Energy Source

This paper presents a concept for an implantable micro-pump based on hydrogen- generating gas cells. The gas-generating cell is separated from the drug reservoir by an expandable latex membrane. The system offers linear drug delivery with flowrates ranging from 8 nl/s to 2 μl/s and a total delivery volume of up to 160 ml. Drugs can be dispensed over a wide backpressure range. The device is scalable based on the size of the gas-producing cell and requires no external energy source. Possible fields of application include in vivo local drug delivery for chemotherapy, diabetes, and pain management.

3D Printed and Additively Manufactured RoboSiC™ for Space, Cryogenic, Laser and Nuclear Environments

2018 ◽  
Vol 2018 (1) ◽  
pp. 000099-000103
Author(s):  
William A. Goodman
Keyword(s):  
Silicon Carbide ◽  
3D Printing ◽  
Phase I ◽  
Areal Density ◽  
Radiation Shielding ◽  
Space Telescope ◽  
3D Print ◽  
3D Printed ◽  
Lattice Construction ◽  
Better Than

Abstract Goodman Technologies has been directly responsive to, and focused on, 3D printing and additive manufacturing techniques, and what it takes to manufacture in zero-gravity. During a NASA Phase I SBIR project, using a small multi-printhead machine, we showed that it was possible to formulate and 3D print silicon carbide into shapes appropriate for lightweight mirrors and structures at the production rate of 1.2 square-meter/day. Gradient lattice coupons with feature sizes on the order of 0.8mm were printed and were easily machined to very fine tolerances, ten-thousandths of an inch by Coastline Optics in Camarillo, CA. To further elaborate on the list of achievements, in Phase I, Team GT demonstrated three different ceramization techniques for 3D printing low areal cost, ultra-lightweight Silicon Carbide (SiC) mirrors and structures, radiation shielding, and electronics, several of which could be employed in microgravity The Goodman Technologies briefing presented at 2017 Mirror Technology Days “3D Printed Silicon Carbide Scalable to Meter-Class Segments for Far-Infrared Surveyor: NASA Contract NNX17CM29P along with sample coupons resulted in extreme interest from both Government and the Contractor communities. Our materials, which we call RoboSiC™, is suited for many other applications including heat sinks and radiation shielding for space electronics, and we have already started to make the first parts for these applications. The successful Phase I project suggests that we will meet or exceed all NASA requirements for the primary mirror of a Far-IR Surveyor such as the Origins Space Telescope (OST) and have a high probability solution for the LUVOIR Surveyor in time for the 2020 Decadal Survey. Results indicate that printing on the ground will achieve an areal density of 7.75 kg/square-meter (~39% of a James Webb Space Telescope (JWST) beryllium segment), a cost to print of $60K/segment, and an optical surface that has nanometer-scale tolerances. Printing in the microgravity environment of space we have the potential to achieve an areal density of 1.0–2.0 kg/square meter (<10% of a JWST beryllium segment), with a cost to print of ~$10K/segment. The areal density is 2–15 times better than the NASA goal of 15 kg/square meter, and the costs are substantially better than the NASA goal of $100K/square meter. The encapsulated gradient lattice construction provides a uniform CTE throughout the part for dimensional stability, incredible specific stiffness, and the added benefit of cryo-damping. For the extreme wavefront control required by the Large UV/Optical/IR Surveyor (LUVOIR) the regularly spaced lattice construction should also provide deterministic mapping of any optical distortions directly to the regular actuator spacing of a deformable mirror (DM). Some of our processes will also allow for direct embedding of electronics for active structures and segments. Encapsulation of the lattice structures will allow for actively cooling with helium for unprecedented low emissivity and thermal control. Several decades of experience and testing with SiC have shown that our materials will survive, nay thrive in, the most extreme Space, Cryogenic, Laser and Nuclear Environments.

Sign in / Sign up

Export Citation Format

Share Document