Generation of Beam Tilt through Three-Dimensional Printed Surface

In this paper, 3D printed surfaces are presented to study this technology’s application in generating beam tilt for the electromagnetic waves in the Ku-band. Additionally, the input source is maintained by a feed horn that is additively manufactured and is coated with copper spray paint to add conductivity, which is fed by a WR-75 waveguide. The proposed beam tilt generating surface is also referred to as a Beam Deviating Surface (BDS). There is no relative gap between the BDS and the aperture of the horn, which eventually decreased the overall antenna height. The BDS layer is able to deviate the beam for a fixed elevation angle of 22.5∘ and could be consequently rotated along with the rotation of the BDS prototype. The voltage standing wave ratio value is less than two over the operating frequency range, which depicts the wideband behavior. The measured and simulated radiation patterns show that we can tilt the electromagnetic waves in ranges of up to +/−22.5∘ with a minimum side lobe level of −5 dB at frequencies from 10 to 15 GHz. This signifies the wideband characteristic of the proposed prototype, which is achieved by Vero material from Multijet Printing that is a low-cost and rapid manufacturing 3D printing technology.

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Ka-Band Lightweight High-Efficiency Wideband 3D Printed Reflector Antenna

International Journal of Antennas and Propagation ◽

10.1155/2017/7360329 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Yu Zhai ◽

Ding Xu ◽

Yan Zhang

Keyword(s):

High Efficiency ◽

Near Field ◽

Side Lobe ◽

High Gain ◽

Reflector Antenna ◽

Field Analysis ◽

Side Lobe Level ◽

Ka Band ◽

3D Printed ◽

Reflecting Surface

This paper presents a lightweight, cost-efficient, wideband, and high-gain 3D printed parabolic reflector antenna in the Ka-band. A 10 λ reflector is printed with polylactic acid- (PLA-) based material that is a biodegradable type of plastic, preferred in 3D printing. The reflecting surface is made up of multiple stacked layers of copper tape, thick enough to function as a reflecting surface (which is found 4 mm). A conical horn is used for the incident field. A center-fed method has been used to converge the energy in the broadside direction. The proposed antenna results measured a gain of 27.8 dBi, a side lobe level (SLL) of −22 dB, and a maximum of 61.2% aperture efficiency (at 30 GHz). A near-field analysis in terms of amplitude and phase has also been presented which authenticates the accurate spherical to planar wavefront transformation in the scattered field.

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Three-Dimensional Chipless RFID Tags: Fabrication through Additive Manufacturing

Sensors ◽

10.3390/s20174740 ◽

2020 ◽

Vol 20 (17) ◽

pp. 4740

Author(s):

Sergio Terranova ◽

Filippo Costa ◽

Giuliano Manara ◽

Simone Genovesi

Keyword(s):

Radio Frequency Identification ◽

Low Cost ◽

Three Dimensional ◽

Rfid Tags ◽

Metallic Surfaces ◽

Data Encoding ◽

Chipless Rfid ◽

Frequency Identification ◽

3D Printed ◽

Promising Solution

A new class of Radio Frequency IDentification (RFID) tags, namely the three-dimensional (3D)-printed chipless RFID one, is proposed, and their performance is assessed. These tags can be realized by low-cost materials, inexpensive manufacturing processes and can be mounted on metallic surfaces. The tag consists of a solid dielectric cylinder, which externally appears as homogeneous. However, the information is hidden in the inner structure of the object, where voids are created to encrypt information in the object. The proposed chipless tag represents a promising solution for anti-counterfeiting or security applications, since it avoids an unwanted eavesdropping during the reading process or information retrieval from a visual inspection that may affect other chipless systems. The adopted data-encoding algorithm does not rely on On–Off or amplitude schemes that are commonly adopted in the chipless RFID implementations but it is based on the maximization of available states or the maximization of non-overlapping regions of uncertainty. The performance of such class of chipless RFID tags are finally assessed by measurements on real prototypes.

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The Sparthan Three-Dimensional Printed Exo-Glove: A Preliminary Evaluation of Performance Via Case Study

Journal of Medical Devices ◽

10.1115/1.4043976 ◽

2019 ◽

Vol 13 (3) ◽

Author(s):

Tomás A. Georgiou ◽

Davide Asnaghi ◽

Alva Liang ◽

Alice M. Agogino

Keyword(s):

Light Intensity ◽

Daily Living ◽

Low Cost ◽

Three Dimensional ◽

Preliminary Evaluation ◽

Evaluation Of Performance ◽

3D Printed ◽

Hand Exoskeleton ◽

And Performance

This paper describes the development and testing of a low-cost three-dimensional (3D) printed wearable hand exoskeleton to assist people with limited finger mobility and grip strength. The function of the presented orthosis is to support and enable light intensity activities of daily living and improve the ability to grasp and hold objects. The Sparthan Exoskeleton prototype utilizes a cable-driven design applied to individual digits with motors. The initial prototype is presented in this paper along with a preliminary evaluation of durability and performance efficacy.

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Development of a Low-Cost EEG-Controlled Hand Exoskeleton 3D Printed on Textiles

Frontiers in Neuroscience ◽

10.3389/fnins.2021.661569 ◽

2021 ◽

Vol 15 ◽

Author(s):

Rommel S. Araujo ◽

Camille R. Silva ◽

Severino P. N. Netto ◽

Edgard Morya ◽

Fabricio L. Brasil

Keyword(s):

Low Cost ◽

Three Dimensional ◽

Training Session ◽

Life Quality ◽

Motor Deficits ◽

Stroke Survivors ◽

Motor Rehabilitation ◽

3D Printed ◽

Hand Exoskeleton ◽

Robotic Devices

Stroke survivors can be affected by motor deficits in the hand. Robotic equipment associated with brain–machine interfaces (BMI) may aid the motor rehabilitation of these patients. BMIs involving orthotic control by motor imagery practices have been successful in restoring stroke patients' movements. However, there is still little acceptance of the robotic devices available, either by patients and clinicians, mainly because of the high costs involved. Motivated by this context, this work aims to design and construct the Hand Exoskeleton for Rehabilitation Objectives (HERO) to recover extension and flexion movements of the fingers. A three-dimensional (3D) printing technique in association with textiles was used to produce a lightweight and wearable device. 3D-printed actuators have also been designed to reduce equipment costs. The actuator transforms the torque of DC motors into linear force transmitted by Bowden cables to move the fingers passively. The exoskeleton was controlled by neuroelectric signal—electroencephalography (EEG). Concept tests were performed to evaluate control performance. A healthy volunteer was submitted to a training session with the exoskeleton, according to the Graz-BCI protocol. Ergonomy was evaluated with a two-dimensional (2D) tracking software and correlation analysis. HERO can be compared to ordinary clothing. The weight over the hand was around 102 g. The participant was able to control the exoskeleton with a classification accuracy of 91.5%. HERO project resulted in a lightweight, simple, portable, ergonomic, and low-cost device. Its use is not restricted to a clinical setting. Thus, users will be able to execute motor training with the HERO at hospitals, rehabilitation clinics, and at home, increasing the rehabilitation intervention time. This may support motor rehabilitation and improve stroke survivors life quality.

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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.

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Use of three-dimensional printing for simulation in ultrasound education: a scoping review

BMJ Simulation and Technology Enhanced Learning ◽

10.1136/bmjstel-2020-000663 ◽

2020 ◽

pp. bmjstel-2020-000663

Author(s):

Patrick Gallagher ◽

Ryan Smith ◽

Gillian Sheppard

Keyword(s):

Scoping Review ◽

Computer Aided Design ◽

Low Cost ◽

Three Dimensional ◽

Low Frequency ◽

Imaging Data ◽

Ultrasound Education ◽

Three Dimensional Printing ◽

3D Printed ◽

Dimensional Printing

BackgroundThere is a significant learning curve when teaching ultrasonography to medical trainees; task trainers can help learners to bridge this gap and develop their skills. Three-dimensional printing technology has the potential to be a great tool in the development of such simulators. ObjectiveThis scoping review aimed to identify what 3D-printed models have been used in ultrasound education to date, how they were created and the pros and limitations involved.DesignResearchers searched three online databases to identify 3D-printed ultrasound models used in medical education.ResultsTwelve suitable publications were identified for inclusion in this review. The models from included articles simulated largely low frequency and/or high stakes events, with many models simulating needle guidance procedures. Most models were created by using patient imaging data and a computer-aided design software to print structures directly or print casting molds. The benefits of 3D-printed educational trainers are their low cost, reproducibility, patient specificity and accuracy. The current limitations of this technology are upfront investments and a lack of optimisation of materials.ConclusionsThe use of 3D-printed ultrasound task trainers is in its infancy, and more research is needed to determine whether or not this technology will benefit medical learners in the future.

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Development of Smartphone-Controlled Hand and Arm Exoskeleton for Persons with Disability

Open Engineering ◽

10.1515/eng-2021-0016 ◽

2020 ◽

Vol 11 (1) ◽

pp. 161-170

Author(s):

J-R. R. Diego ◽

Dan William C. Martinez ◽

Gerald S. Robles ◽

John Ryan C. Dizon

Keyword(s):

3D Printing ◽

Low Cost ◽

Three Dimensional ◽

Prosthetic Device ◽

Three Dimensional Printing ◽

Plastic Materials ◽

3D Printed ◽

Available Technology ◽

Electronic Parts ◽

Dimensional Printing

AbstractThis study addresses the need for assistive technology of people who lost control of their upper limbs as well as people who are undergoing rehabilitation. Loss of upper limb control causes lack of functionality and social acceptability especially for many people in developing countries with fewer available technology. The study develops a modern but low-cost prosthetic device that can be controlled by users using a smartphone and can be rapidly manufactured using three-dimensional printing (3D printing) of plastic materials. The development of the prosthetic device includes designing the mechanical and electronic parts, programming the Arduino board and Android application for control, simulation and analysis of 3D printed parts most subjected to stress, and 3D printing the parts under different settings. The device was tested in terms of time spent and capacity of lifting varying loads when not worn and when worn by users. The device can effectively lift 500 grams of load in one second for a person weighing between 50 to 60 kilograms.

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Binaural Modelling and Spatial Auditory Cue Analysis of 3D-Printed Ears

Sensors ◽

10.3390/s21010227 ◽

2021 ◽

Vol 21 (1) ◽

pp. 227

Author(s):

Te Meng Ting ◽

Nur Syazreen Ahmad ◽

Patrick Goh ◽

Junita Mohamad-Saleh

Keyword(s):

Sound Source ◽

Elevation Angle ◽

Three Dimensional ◽

Estimation Method ◽

Distance Estimation ◽

Outdoor Environment ◽

Average Error ◽

Spectral Cues ◽

Polar Coordinate ◽

3D Printed

In this work, a binaural model resembling the human auditory system was built using a pair of three-dimensional (3D)-printed ears to localize a sound source in both vertical and horizontal directions. An analysis on the proposed model was firstly conducted to study the correlations between the spatial auditory cues and the 3D polar coordinate of the source. Apart from the estimation techniques via interaural and spectral cues, the property from the combined direct and reverberant energy decay curve is also introduced as part of the localization strategy. The preliminary analysis reveals that the latter provides a much more accurate distance estimation when compared to approximations via sound pressure level approach, but is alone not sufficient to disambiguate the front-rear confusions. For vertical localization, it is also shown that the elevation angle can be robustly encoded through the spectral notches. By analysing the strengths and shortcomings of each estimation method, a new algorithm is formulated to localize the sound source which is also further improved by cross-correlating the interaural and spectral cues. The proposed technique has been validated via a series of experiments where the sound source was randomly placed at 30 different locations in an outdoor environment up to a distance of 19 m. Based on the experimental and numerical evaluations, the localization performance has been significantly improved with an average error of 0.5 m from the distance estimation and a considerable reduction of total ambiguous points to 3.3%.

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Photocatalytic Properties of Eco-Friendly ZnO Nanostructures on 3D-Printed Polylactic Acid Scaffolds

Nanomaterials ◽

10.3390/nano11010168 ◽

2021 ◽

Vol 11 (1) ◽

pp. 168

Author(s):

Maria Sevastaki ◽

Vassilis M. Papadakis ◽

Cosmin Romanitan ◽

Mirela Petruta Suchea ◽

George Kenanakis

Keyword(s):

Polylactic Acid ◽

Large Scale ◽

Low Cost ◽

Three Dimensional ◽

Real Life ◽

Ammonium Bicarbonate ◽

Research Report ◽

Zno Nanostructures ◽

Pure Ethanol ◽

3D Printed

The present paper reports a novel approach for fabrication of eco-friendly ZnO nanoparticles onto three-dimensional (3D)-printed polylactic acid (PLA) scaffolds/structures. Several alcohol-based traditional Greek liquors were used to achieve the corrosion of metallic zinc collected from a typical galvanic anode to obtain photocatalytic active nanostructured ZnO, varying from water, to Greek “ouzo” and “raki”, and pure ethanol, in combination with “Baker’s ammonia” (ammonium bicarbonate), sold worldwide in every food store. The photocatalytic active ZnO nanostructures onto three-dimensional (3D)-printed PLA scaffolds were used to achieve the degradation of 50 ppm paracetamol in water, under UV irradiation. This study provides evidence that following the proposed low-cost, eco-friendly routes for the fabrication of large-scale photocatalysts, an almost 95% degradation of 50 ppm paracetamol in water can be achieved, making the obtained 3D ZnO/PLA structures excellent candidates for real life environmental applications. This is the first literature research report on a successful attempt of using this approach for the engineering of low-cost photocatalytic active elements for pharmaceutical contaminants in waters.

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A 3D Printed Modular Soft Gripper Integrated With Metamaterials for Conformal Grasping

Frontiers in Robotics and AI ◽

10.3389/frobt.2021.799230 ◽

2022 ◽

Vol 8 ◽

Author(s):

Charbel Tawk ◽

Rahim Mutlu ◽

Gursel Alici

Keyword(s):

Contact Pressure ◽

Fused Deposition Modeling ◽

Low Cost ◽

Three Dimensional ◽

Single Step ◽

Positive Pressure ◽

Pneumatic Actuators ◽

Fused Deposition ◽

3D Printed ◽

And Performance

A single universal robotic gripper with the capacity to fulfill a wide variety of gripping and grasping tasks has always been desirable. A three-dimensional (3D) printed modular soft gripper with highly conformal soft fingers that are composed of positive pressure soft pneumatic actuators along with a mechanical metamaterial was developed. The fingers of the soft gripper along with the mechanical metamaterial, which integrates a soft auxetic structure and compliant ribs, was 3D printed in a single step, without requiring support material and postprocessing, using a low-cost and open-source fused deposition modeling (FDM) 3D printer that employs a commercially available thermoplastic poly (urethane) (TPU). The soft fingers of the gripper were optimized using finite element modeling (FEM). The FE simulations accurately predicted the behavior and performance of the fingers in terms of deformation and tip force. Also, FEM was used to predict the contact behavior of the mechanical metamaterial to prove that it highly decreases the contact pressure by increasing the contact area between the soft fingers and the grasped objects and thus proving its effectiveness in enhancing the grasping performance of the gripper. The contact pressure can be decreased by up to 8.5 times with the implementation of the mechanical metamaterial. The configuration of the highly conformal gripper can be easily modulated by changing the number of fingers attached to its base to tailor it for specific manipulation tasks. Two-dimensional (2D) and 3D grasping experiments were conducted to assess the grasping performance of the soft modular gripper and to prove that the inclusion of the metamaterial increases its conformability and reduces the out-of-plane deformations of the soft monolithic fingers upon grasping different objects and consequently, resulting in the gripper in three different configurations including two, three and four-finger configurations successfully grasping a wide variety of objects.

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