Development of a 3D Printed Double-Acting Linear Pneumatic Actuator for the Tendon Gripping

The lack of standardization in tissue testing procedures results in a variety of custom-made devices. In the case of the determination of the mechanical properties of tendons, it is sometimes necessary to adapt the existing laboratory equipment for conducting experiments when specific commercial equipment is not applicable to solve issues such as proper gripping to prevent tendon slipping and rupturing, gripping control and manoeuvrability in case of tendon submerging and without contamination of the testing liquid. This paper presents the systematic development, design, and fabrication using 3D printing technology and the application of the double-acting linear pneumatic actuator to overcome such issues. It is designed to do its work submerged in the Ringers’ solution while gripping the tendon along with the clamps. The pneumatic foot valve unit of the Shimadzu AGS-X tensile testing machine controls the actuator thus preventing Ringers’ solution to be contaminated by the machine operator during specimen set-up. The actuator has a length of 60 mm, a bore of 50 mm, and a stroke length of 20 mm. It is designed to operate with an inlet pressure of up to 0.8 MPa. It comprises the cylinder body with the integrated thread, the piston, the piston head, and the gripper jaw. Fused deposition modeling (FDM) has been used as the 3D printing technique, along with polylactic acid (PLA) as the material for 3D printing. The 3D printed double-acting linear pneumatic actuator was developed into an operating prototype. This study could open new frontiers in the field of tissue testing and the development of similar specialized devices for medical purposes.

Download Full-text

3D Printed Clamps for In Vitro Tensile Tests of Human Gracilis and the Superficial Third of Quadriceps Tendons

Applied Sciences ◽

10.3390/app11062563 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2563

Author(s):

Ivan Grgić ◽

Vjekoslav Wertheimer ◽

Mirko Karakašić ◽

Željko Ivandić

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Tensile Tests ◽

Biomechanical Properties ◽

Testing Procedure ◽

Laboratory Equipment ◽

Fused Deposition ◽

Custom Made ◽

3D Printed

Recent soft tissue studies have reported issues that occur during experimentation, such as the tissue slipping and rupturing during tensile loads, the lack of standard testing procedure and equipment, the necessity for existing laboratory equipment adaptation, etc. To overcome such issues and fulfil the need for the determination of the biomechanical properties of the human gracilis and the superficial third of the quadriceps tendons, 3D printed clamps with metric thread profile-based geometry were developed. The clamps’ geometry consists of a truncated pyramid pattern, which prevents the tendons from slipping and rupturing. The use of the thread application in the design of the clamp could be used in standard clamping development procedures, unlike in previously custom-made clamps. Fused deposition modeling (FDM) was used as a 3D printing technique, together with polylactic acid (PLA), which was used as a material for clamp printing. The design was confirmed and the experiments were conducted by using porcine and human tendons. The findings justify the usage of 3D printing technology for parts manufacturing in the case of tissue testing and establish independence from the existing machine clamp system, since it was possible to print clamps for each prepared specimen and thus reduce the time for experiment setup.

Download Full-text

Biodegradable 3D Printed Polymer Microneedles for Transdermal Drug Delivery

10.26434/chemrxiv.5851950.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Michael A. Luzuriaga ◽

Danielle R. Berry ◽

John C. Reagan ◽

Ronald A. Smaldone ◽

Jeremiah J. Gassensmith

Keyword(s):

Drug Delivery ◽

3D Printing ◽

Transdermal Drug Delivery ◽

Fused Deposition Modeling ◽

Fused Deposition ◽

Modeling Software ◽

Deposition Modeling ◽

3D Printed ◽

Microfabrication Technique ◽

Mechanical Strengths

Biodegradable polymer microneedle (MN) arrays are an emerging class of transdermal drug delivery devices that promise a painless and sanitary alternative to syringes; however, prototyping bespoke needle architectures is expensive and requires production of new master templates. Here, we present a new microfabrication technique for MNs using fused deposition modeling (FDM) 3D printing using polylactic acid, an FDA approved, renewable, biodegradable, thermoplastic material. We show how this natural degradability can be exploited to overcome a key challenge of FDM 3D printing, in particular the low resolution of these printers. We improved the feature size of the printed parts significantly by developing a post fabrication chemical etching protocol, which allowed us to access tip sizes as small as 1 μm. With 3D modeling software, various MN shapes were designed and printed rapidly with custom needle density, length, and shape. Scanning electron microscopy confirmed that our method resulted in needle tip sizes in the range of 1 – 55 µm, which could successfully penetrate and break off into porcine skin. We have also shown that these MNs have comparable mechanical strengths to currently fabricated MNs and we further demonstrated how the swellability of PLA can be exploited to load small molecule drugs and how its degradability in skin can release those small molecules over time.

Download Full-text

Mechanical Characterization and Thermodynamic Analysis of Laser-Polished Landscape Design Products Using 3D Printing

Materials ◽

10.3390/ma14102601 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2601

Author(s):

Yue Ba ◽

Yu Wen ◽

Shibin Wu

Keyword(s):

Surface Roughness ◽

3D Printing ◽

Fused Deposition Modeling ◽

High Surface ◽

Landscape Design ◽

Laser Polishing ◽

Fused Deposition ◽

Design Structure ◽

3D Printed ◽

Stability And Accuracy

Recent innovations in 3D printing technologies and processes have influenced how landscape products are designed, built, and developed. In landscape architecture, reduced-size models are 3D-printed to replicate full-size structures. However, high surface roughness usually occurs on the surfaces of such 3D-printed components, which requires additional post-treatment. In this work, we develop a new type of landscape design structure based on the fused deposition modeling (FDM) technique and present a laser polishing method for FDM-fabricated polylactic acid (PLA) mechanical components, whereby the surface roughness of the laser-polished surfaces is reduced from over Ra 15 µm to less than 0.25 µm. The detailed results of thermodynamics and microstructure evolution are further analyzed during laser polishing. The stability and accuracy of the results are evaluated based on the standard deviation. Additionally, the superior tensile and flexural properties are examined in the laser-polished layer, in which the ultimate tensile strength (UTS) is increased by up to 46.6% and the flexural strength is increased by up to 74.5% compared with the as-fabricated components. Finally, a real polished landscape model is simulated and optimized using a series of scales.

Download Full-text

3D-Printable PP/SEBS Thermoplastic Elastomeric Blends: Preparation and Properties

Polymers ◽

10.3390/polym11020347 ◽

2019 ◽

Vol 11 (2) ◽

pp. 347 ◽

Cited By ~ 18

Author(s):

Shib Banerjee ◽

Stephen Burbine ◽

Nischay Kodihalli Shivaprakash ◽

Joey Mead

Keyword(s):

3D Printing ◽

Carbon Black ◽

Computer Aided Design ◽

Fused Deposition Modeling ◽

Mechanical Performance ◽

Polymeric Materials ◽

Fused Deposition ◽

3D Printed ◽

Injection Molded ◽

Preferential Location

Currently, material extrusion 3D printing (ME3DP) based on fused deposition modeling (FDM) is considered a highly adaptable and efficient additive manufacturing technique to develop components with complex geometries using computer-aided design. While the 3D printing process for a number of thermoplastic materials using FDM technology has been well demonstrated, there still exists a significant challenge to develop new polymeric materials compatible with ME3DP. The present work reports the development of ME3DP compatible thermoplastic elastomeric (TPE) materials from polypropylene (PP) and styrene-(ethylene-butylene)-styrene (SEBS) block copolymers using a straightforward blending approach, which enables the creation of tailorable materials. Properties of the 3D printed TPEs were compared with traditional injection molded samples. The tensile strength and Young’s modulus of the 3D printed sample were lower than the injection molded samples. However, no significant differences could be found in the melt rheological properties at higher frequency ranges or in the dynamic mechanical behavior. The phase morphologies of the 3D printed and injection molded TPEs were correlated with their respective properties. Reinforcing carbon black was used to increase the mechanical performance of the 3D printed TPE, and the balancing of thermoplastic elastomeric and mechanical properties were achieved at a lower carbon black loading. The preferential location of carbon black in the blend phases was theoretically predicted from wetting parameters. This study was made in order to get an insight to the relationship between morphology and properties of the ME3DP compatible PP/SEBS blends.

Download Full-text

Properties and applications of electrically conductive thermoplastics for additive manufacturing of sensors

tm - Technisches Messen ◽

10.1515/teme-2016-0057 ◽

2017 ◽

Vol 84 (9) ◽

Cited By ~ 6

Author(s):

Benedikt Hampel ◽

Samuel Monshausen ◽

Meinhard Schilling

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Electrical Conductance ◽

Electrically Conductive ◽

Fused Deposition ◽

Printing Technique ◽

Deposition Modeling ◽

3D Printed ◽

3D Printing Technique ◽

Printing Parameters

AbstractIn consequence of the growing diversity of materials in the fused deposition modeling 3D printing technique, electrically conductive materials are commercially available. In this work two filaments based on thermoplastics filled with carbon or metal nanoparticles are analyzed in terms of their electrical conductance. The printing parameters to process the materials with the 3D printer are optimized with the design of experiments (DoE) method. A model to calculate the resistance of such 3D printed structures is presented and a demonstrator as a proof of concept was 3D printed based on these results. In addition, 3D printing of capacitors is investigated.

Download Full-text

Development and Accuracy Test of a Fused Deposition Modeling (FDM) 3D Printing using H-Bot Mechanism

Indonesian Journal of Computing, Engineering and Design (IJoCED) ◽

10.35806/ijoced.v3i1.148 ◽

2021 ◽

Vol 3 (1) ◽

pp. 46-53

Author(s):

Budi Hadisujoto ◽

Robby Wijaya

Keyword(s):

3D Printing ◽

Manufacturing Process ◽

Fused Deposition Modeling ◽

Industrial Revolution ◽

3D Printer ◽

Initial Development ◽

Fused Deposition ◽

Accuracy Test ◽

Custom Made ◽

Deposition Modeling

Additive manufacturing process known as the 3D printing process is an advanced manufacturing process including one of the components to support industrial revolution 4.0. The initial development of a 3D printing machine at Sampoerna University is the background of this research. The 3D printing setup of Fused Deposition Modeling (FDM) was built using H-bot moving mechanism by considering the rigidity aspect. The FDM printing method is selected due to its cost and reliability. In this early development, the brackets were custom made using a 3D printer with Polylactic Acid (PLA) material. The result showed that the software worked properly in accordance with the assembled mechanical and electrical parts. The 3D printer could print simple objects such as planes and cubes with small dimensions. However, the printing specimen still lacked accuracy caused by the less rigidity of linear rail brackets, less coplanar belt arrangement, and error in some electronic components.

Download Full-text

An overview on 3D Printed Medicine

Material Science Research India ◽

10.13005/msri/180102 ◽

2021 ◽

Vol 18 (1) ◽

pp. 07-13

Author(s):

Neha Thakur ◽

Hari Murthy

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Low Cost ◽

Selective Laser Sintering ◽

Three Dimensional ◽

Herbal Medicines ◽

Fused Deposition ◽

Digitally Controlled ◽

3D Printed ◽

Semi Solid

Three-dimensional printing (3DP) is a digitally-controlled additive manufacturing technique used for fast prototyping. This paper reviews various 3D printing techniques like Selective Laser Sintering (SLS), Fused Deposition Modeling, (FDM), Semi-solid extrusion (SSE), Stereolithography (SLA), Thermal Inkjet (TIJ) Printing, and Binder jetting 3D Printing along with their application in the field of medicine. Normal medicines are based on the principle of “one-size-fits-all”. This is not true always, it is possible medicine used for curing one patient is giving some side effects to another. To overcome this drawback “3D Printed medicines” are developed. In this paper, 3D printed medicines forming different Active Pharmaceutical Ingredients (API) are reviewed. Printed medicines are capable of only curing the diseases, not for the diagnosis. Nanomedicines have “theranostic” ability which combines therapeutic and diagnostic. Nanoparticles are used as the drug delivery system (DDS) to damaged cells’ specific locations. By the use of nanomedicine, the fast recovery of the disease is possible. The plant-based nanoparticles are used with herbal medicines which give low-cost and less toxic medication called nanobiomedicine. 4D and 5D printing technology for the medical field are also enlightened in this paper.

Download Full-text

Effects of wood flour and MA-EPDM on the properties of fused deposition modeling 3D-printed poly lactic acid composites

BioResources ◽

10.15376/biores.16.4.7122-7138 ◽

2021 ◽

Vol 16 (4) ◽

pp. 7122-7138

Author(s):

Sang-U Bae ◽

Young-Rok Seo ◽

Birm-June Kim ◽

Min Lee

Keyword(s):

Lactic Acid ◽

3D Printing ◽

Fused Deposition Modeling ◽

Wood Flour ◽

Poly Lactic Acid ◽

Common System ◽

Fused Deposition ◽

Deposition Modeling ◽

3D Printed ◽

Material Composite

Fused deposition modeling (FDM) 3D printing technology is the most common system for polymer additive manufacturing (AM). Recent studies have been conducted to expand both the range of materials that can be used for FDM and their applications. As a filler, wood flour was incorporated into poly lactic acid (PLA) polymer to develop a biocomposite material. Composite filaments were manufactured with various wood flour contents and then successfully used for 3D printing. Morphological, mechanical, and biodegradation properties of FDM 3D-printed PLA composites were investigated. To mitigate brittleness, 5 phr of maleic anhydride grafted ethylene propylene diene monomer (MA-EPDM) was added to the composite blends, and microstructural properties of the composites were examined by scanning electron microscopy (SEM). Mechanical strength tests demonstrated that elasticity was imparted to the composites. Additionally, test results showed that the addition of wood flour to the PLA matrix promoted pore generation and further influenced the mechanical and biodegradation properties of the 3D-printed composites. An excellent effect of wood flour on the biodegradation properties of FDM 3D-printed PLA composites was observed.

Download Full-text

COVID-19 and a novel initiative to improve safety by 3D printing personal protective equipment parts from computed tomography

10.21203/rs.3.rs-31671/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

John Cote ◽

John Haggstrom ◽

Ranuga Vivkanandan ◽

Kristin Ann Coté ◽

Daniel Real ◽

...

Keyword(s):

Computed Tomography ◽

3D Printing ◽

Fused Deposition Modeling ◽

Future Research ◽

Short Supply ◽

Fused Deposition ◽

Electronic Caliper ◽

3D Printed ◽

Original Part ◽

Improved Accuracy

Abstract Background Powered air-purifying respirators are in short supply and can break down with extended use. Replacement parts can become hard to acquire. The aim of this study was to create an innovative quality improvement proof of concept using rapid prototyping. Methods Here we report three cases of 3D printed powered air-purifying respirator parts. 3D printing was performed on all parts using fused deposition modeling with standard polylactic acid, in the same way that presurgical models would be created. Measurements using an electronic caliper as well as CT scans were used to compare an original part to its corresponding 3D printed parts for accuracy. Results Electronic caliper and computed tomography measurements both showed accuracy consistant with current published norms. Conclusions Ultimately, there will be questions surrounding intellectual property, effectiveness and potential long-term safety for these types of 3D printed parts. Future research should look into the addition of specific nanoparticles from the position of cost, efficacy, safety and improved accuracy.

Download Full-text

Stabilization of Electrospun Nanofiber Mats Used for Filters by 3D Printing

Polymers ◽

10.3390/polym11101618 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1618 ◽

Cited By ~ 11

Author(s):

Kozior ◽

Trabelsi ◽

Mamun ◽

Sabantina ◽

Ehrmann

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Water Pressure ◽

Volume Ratio ◽

Fused Deposition ◽

Rigid Objects ◽

Deposition Modeling ◽

3D Printed ◽

Printed Materials ◽

Nanofiber Mats

Electrospinning is a well-known technology used to create nanofiber mats from diverse polymers and other materials. Due to their large surface-to-volume ratio, such nanofiber mats are often applied as air or water filters. Especially the latter, however, have to be mechanically highly stable, which is challenging for common nanofiber mats. One of the approaches to overcome this problem is gluing them on top of more rigid objects, integrating them in composites, or reinforcing them using other technologies to avoid damage due to the water pressure. Here, we suggest another solution. While direct 3D printing with the fused deposition modeling (FDM) technique on macroscopic textile fabrics has been under examination by several research groups for years, here we report on direct FDM printing on nanofiber mats for the first time. We show that by choosing the proper height of the printing nozzle above the nanofiber mat, printing is possible for raw polyacrylonitrile (PAN) nanofiber mats, as well as for stabilized and even more brittle carbonized material. Under these conditions, the adhesion between both parts of the composite is high enough to prevent the nanofiber mat from being peeled off the 3D printed polymer. Abrasion tests emphasize the significantly increased mechanical properties, while contact angle examinations reveal a hydrophilicity between the original values of the electrospun and the 3D printed materials.

Download Full-text