Design and Fabrication of Hierarchical Multi-Stable Structures Through Multi-Material Additive Manufacturing

2016 ◽  
Author(s):  
Tian Chen ◽  
Kristina Shea
Keyword(s):  
Additive Manufacturing ◽  
Design Procedure ◽  
The Novel ◽  
Proof Of Concept ◽  
Form Finding ◽  
Out Of Plane ◽  
3D Printed ◽  
Novel Structures ◽  
Design For Am ◽  
Stable Structures

The design and fabrication of hierarchical multi-stable structures using multi-material Additive Manufacturing (AM) is presented. First a reversible bistable unit actuator is designed to serve as the basis of the design hierarchy. With this unit actuator, the authors present monolithically printed proof-of-concept structures that can transform to multiple activated states, all of which are stable without the need for continuous energy input. The equilibrium positions of these hierarchical designs are found through iterative form finding when necessary. The novel structures illustrated in this paper are only made possible through design for AM that exploits the capabilities of a multi-material, inkjet 3D printer. The design procedure is illustrated through two concepts. The first consists of a series of tetrahedra fabricated as tiled deployable triangles with the out-of-plane members consisting of the actuators in the retracted configuration. The second concept consists of multiple shape changing square unit modules tiled in a grid to achieve complex 3D activated states including a hemisphere, a hyperbolic paraboloid, a star and a cube. Their design and prototyping form the foundation for new types of active and deployable 3D printed structures.

scholarly journals Closing the Loop - Recycling Plastic Waste

2021 ◽  
Author(s):  
◽  
Caitlin Bruce
Keyword(s):  
New Zealand ◽  
Additive Manufacturing ◽  
Circular Economy ◽  
Building Material ◽  
New Technologies ◽  
Plastic Waste ◽  
Proof Of Concept ◽  
Waste Production ◽  
Closing The Loop ◽  
3D Printed

<p>New Zealand is ranked among the top nations in waste production, including a million tonnes of plastic waste. Currently, there are methods for recycling plastic within New Zealand but these methods can be expensive and time-consuming, resulting in most of the plastic being thrown into the landfill. Because plastic does not fully degrade, it ends up in the ocean and other waterways, poisoning the water with toxins. The purpose of this research is to provide a solution to reducing plastic waste by creating an alternative method of recycling that utilises new technologies such as additive manufacturing, to create a building material that fits into the concept of the circular economy. The findings of this research explored the recycling of plastic by collecting plastic waste such as PLA (Polylactic Acid) from old 3D printed models. The plastic was recycled into filament for additive manufacturing (AM) and used to print building tile, establishing an initial proof of concept for the use of recycled plastic as a potential building material.</p>

scholarly journals Closing the Loop - Recycling Plastic Waste

2021 ◽  
Author(s):  
◽  
Caitlin Bruce
Keyword(s):  
New Zealand ◽  
Additive Manufacturing ◽  
Circular Economy ◽  
Building Material ◽  
New Technologies ◽  
Plastic Waste ◽  
Proof Of Concept ◽  
Waste Production ◽  
Closing The Loop ◽  
3D Printed

<p>New Zealand is ranked among the top nations in waste production, including a million tonnes of plastic waste. Currently, there are methods for recycling plastic within New Zealand but these methods can be expensive and time-consuming, resulting in most of the plastic being thrown into the landfill. Because plastic does not fully degrade, it ends up in the ocean and other waterways, poisoning the water with toxins. The purpose of this research is to provide a solution to reducing plastic waste by creating an alternative method of recycling that utilises new technologies such as additive manufacturing, to create a building material that fits into the concept of the circular economy. The findings of this research explored the recycling of plastic by collecting plastic waste such as PLA (Polylactic Acid) from old 3D printed models. The plastic was recycled into filament for additive manufacturing (AM) and used to print building tile, establishing an initial proof of concept for the use of recycled plastic as a potential building material.</p>

Novel Design of Legged Mobile Landers With Decoupled Landing and Walking Functions Containing a Rhombus Joint

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Rongfu Lin ◽  
Weizhong Guo ◽  
Meng Li
Keyword(s):  
Autonomous Robots ◽  
Design Procedure ◽  
The Novel ◽  
Type Synthesis ◽  
Typical Structure ◽  
New Approach ◽  
Lie Group Theory ◽  
First Time ◽  
Novel Structures ◽  
Novel Design

During extraterrestrial planetary exploration programs, autonomous robots are deployed using a separate immovable lander and rover. This mode has some limitations. In this paper, a concept of a novel legged robot with decoupled functions was introduced that has inbuilt features of a lander and rover. Currently, studies have focused mainly on performance analysis of the lander without a walking function. However, a systematic type synthesis of the legged mobile lander has not been studied. In this paper, a new approach to the type synthesis used for the robot was proposed based on the Lie group theory. The overall concept and design procedure were proposed and described. The motion requirements of the robot and its legs were extracted and described intuitively. The layouts of the subgroups or submanifolds of the limbs were determined. A family of particular joints with one rotation and one translation was proposed for the first time. The structures of the limbs were synthesized. Numerous structures of the legs were produced and listed corresponding to the desired displacement manifolds. Numerous novel structures of the legs for legged mobile lander were evaluated and listed. Then, four qualitative criteria were introduced. Based on the proposed criteria, a particular case of legs' configuration with a rhombus joint was selected as the best one among them. A typical structure of the legged mobile lander was obtained by assembling the structures of the proposed legs with a rhombus joint. Finally, the typical robot was used as an example to verify the capabilities of the novel robot using a software simulation (adams).

Categorization of Design for Additive Manufacturing Concepts

2019 ◽  
Author(s):  
Sergei Chekurov
Keyword(s):  
Additive Manufacturing ◽  
Heat Exchanger ◽  
Research Community ◽  
Research Field ◽  
Generic Product ◽  
Proof Of Concept ◽  
Design For Additive Manufacturing ◽  
Research Article ◽  
The Many ◽  
Design For Am

Abstract Design for AM (DfAM) has become a widely followed research field with practitioners outside of the research community looking for instructions and inspiration on how to leverage the unique capabilities of AM in their products. The research community has responded by producing an abundance of valuable DfAM literature. However, although each individual research article is useful and can answer specific questions, the connection between them can be difficult to fathom due to the lack of a structured overview of DfAM. This paper proposes a categorization framework to organize the many concepts of DfAM in a structured manner. The framework for the categorization used in this paper is based on a widely used generic product design workflow of Pahl and Beitz that is augmented with concepts from AM literature. The framework is a tool for researchers to position their work in relation to other literature, and it can also be used as a support to achieve novel product designs with AM. To demonstrate how the framework can be used for guided design, the paper presents every stage of the design process in the context of designing a proof-of-concept heat exchanger that leverages the technical benefits of AM.

scholarly journals Vent-Lock: A 3D Printed Ventilator Multiplexer to Enhance the Capacity of Treating Patients with COVID-19

2020 ◽  
Author(s):  
Helen Xun ◽  
Christopher Shallal ◽  
Justin Unger ◽  
Runhan Tao ◽  
Alberto Torres ◽  
...  
Keyword(s):  
Distress Syndrome ◽  
De Novo ◽  
Cost Effective ◽  
The Novel ◽  
Proof Of Concept ◽  
Mechanical Ventilators ◽  
Respiratory Therapists ◽  
Flow Restriction ◽  
3D Printed ◽  
Critical Components

Mechanical ventilators are essential to patients who become critically ill from acute respiratory distress syndrome (ARDS), and shortages have been reported due to the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We utilized cost-effective, on-demand 3D printing (3DP) technology to produce critical components for a novel ventilator multiplexer system, Vent-Lock, to split one ventilator or anesthesia gas machine between two patients. FloRest, a novel 3DP flow restrictor, provides clinicians control of tidal volumes and positive end expiratory pressure (PEEP), using the 3DP manometer adaptor to monitor pressures. We tested the ventilator splitter circuit in simulation centers between artificial lungs and used an anesthesia gas machine to successfully ventilate two swines. As one of the first studies to demonstrate splitting one anesthesia gas machine between two swines, we present proof-of-concept of a de novo, closed, multiplexing system, with flow restriction for individualized patient therapy. Our studies underscore that while possible, ventilator multiplexing is a complicated synergy between machine settings, circuit modification, and patient monitoring. Consequently, ventilator multiplexing is reserved only as a last emergency resource, by trained clinicians and respiratory therapists with ventilator operative experience.

AM-Serienproduktion für die Automobilindustrie/AM series production for the automotive industry

2020 ◽  
Vol 110 (11-12) ◽  
pp. 752-757
Author(s):  
Lukas Weiser ◽  
Marco Batschkowski ◽  
Niclas Eschner ◽  
Benjamin Häfner ◽  
Ingo Neubauer ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Automotive Industry ◽  
Series Production ◽  
Production Scale ◽  
Additive Fertigung ◽  
Small Series ◽  
Start Up ◽  
3D Printed ◽  
Component Quality

Die additive Fertigung schafft neue Gestaltungsfreiheiten. Im Rahmen des Prototypenbaus und der Kleinserienproduktion kann das Verfahren des selektiven Laserschmelzens genutzt werden. Die Verwendung in der Serienproduktion ist bisher aufgrund unzureichender Bauteilqualität, langen Anlaufzeiten sowie mangelnder Automatisierung nicht im wirtschaftlichen Rahmen möglich. Das Projekt „ReAddi“ möchte eine erste prototypische Serienfertigung entwickeln, mit der additiv gefertigte Bauteile für die Automobilindustrie wirtschaftlich produziert werden können. Additive manufacturing (AM) offers new freedom of design. The selective laser-powderbed fusion (L-PBF) process can be used for prototyping and small series production. So far, it has not been economical to use it on a production scale due to insufficient component quality, long start-up times and a lack of automation. The project ReAddi aims to develop a first prototype series production to cost-effectively manufacture 3D-printed components for the automotive industry.

scholarly journals Direct antivirals working against the novel coronavirus: azithromycin (DAWn-AZITHRO), a randomized, multicenter, open-label, adaptive, proof-of-concept clinical trial of new antivirals working against SARS-CoV-2—azithromycin trial

Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Iwein Gyselinck ◽  
◽  
Laurens Liesenborghs ◽  
Ewout Landeloos ◽  
Ann Belmans ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Standard Of Care ◽  
Ordinal Scale ◽  
Cytokine Signaling ◽  
Nasopharyngeal Swab ◽  
The Novel ◽  
Proof Of Concept ◽  
Open Label ◽  
Novel Coronavirus

Abstract Background The rapid emergence and the high disease burden of the novel coronavirus SARS-CoV-2 have created a medical need for readily available drugs that can decrease viral replication or blunt the hyperinflammatory state leading to severe COVID-19 disease. Azithromycin is a macrolide antibiotic, known for its immunomodulatory properties. It has shown antiviral effect specifically against SARS-CoV-2 in vitro and acts on cytokine signaling pathways that have been implicated in COVID-19. Methods DAWn-AZITHRO is a randomized, open-label, phase 2 proof-of-concept, multicenter clinical trial, evaluating the safety and efficacy of azithromycin for treating hospitalized patients with COVID-19. It is part of a series of trials testing promising interventions for COVID-19, running in parallel and grouped under the name DAWn-studies. Patients hospitalized on dedicated COVID wards are eligible for study inclusion when they are symptomatic (i.e., clinical or radiological signs) and have been diagnosed with COVID-19 within the last 72 h through PCR (nasopharyngeal swab or bronchoalveolar lavage) or chest CT scan showing typical features of COVID-19 and without alternate diagnosis. Patients are block-randomized (9 patients) with a 2:1 allocation to receive azithromycin plus standard of care versus standard of care alone. Standard of care is mostly supportive, but may comprise hydroxychloroquine, up to the treating physician’s discretion and depending on local policy and national health regulations. The treatment group receives azithromycin qd 500 mg during the first 5 consecutive days after inclusion. The trial will include 284 patients and recruits from 15 centers across Belgium. The primary outcome is time from admission (day 0) to life discharge or to sustained clinical improvement, defined as an improvement of two points on the WHO 7-category ordinal scale sustained for at least 3 days. Discussion The trial investigates the urgent and still unmet global need for drugs that may impact the disease course of COVID-19. It will either provide support or else justify the discouragement of the current widespread, uncontrolled use of azithromycin in patients with COVID-19. The analogous design of other parallel trials of the DAWN consortium will amplify the chance of identifying successful treatment strategies and allow comparison of treatment effects within an identical clinical context. Trial registration EU Clinical trials register EudraCT Nb 2020-001614-38. Registered on 22 April 2020

Fused Filament Fabrication 3D Printed Polylactic Acid Electroosmotic Pumps

Lab on a Chip ◽  
2021 ◽  
Author(s):  
Liang Wu ◽  
Stephen Beirne ◽  
Joan-Marc Cabot Canyelles ◽  
Brett Paull ◽  
Gordon G. Wallace ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
3D Printing ◽  
Polylactic Acid ◽  
Fused Filament Fabrication ◽  
Flexible Approach ◽  
Electroosmotic Pump ◽  
3D Printed ◽  
Electroosmotic Pumps

Additive manufacturing (3D printing) offers a flexible approach for the production of bespoke microfluidic structures such as the electroosmotic pump. Here a readily accessible fused filament fabrication (FFF) 3D printing...

Numerical and experimental investigation for enhancing the energy absorption capacity of the novel three-dimensional printed sandwich structures

2021 ◽  
pp. 146442072199749
Author(s):  
H Geramizadeh ◽  
S Dariushi ◽  
S Jedari Salami
Keyword(s):  
Energy Absorption ◽  
Sandwich Structures ◽  
Three Dimensional ◽  
Absorption Capacity ◽  
The Novel ◽  
Energy Absorption Capacity ◽  
Fused Deposition ◽  
Honeycomb Sandwich ◽  
Out Of Plane ◽  
Vertical Walls

The current study focuses on designing the optimal three-dimensional printed sandwich structures. The main goal is to improve the energy absorption capacity of the out-of-plane honeycomb sandwich beam. The novel Beta VI and Alpha VI were designed in order to achieve this aim. In the Beta VI, the connecting curves (splines) were used instead of the four diagonal walls, while the two vertical walls remained unchanged. The Alpha VI is a step forward on the Beta VI, which was promoted by filleting all angles among the vertical walls, created arcs, and face sheets. The two offered sandwich structures have not hitherto been provided in the literature. All models were designed and simulated by the CATIA and ABAQUS, respectively. The three-dimensional printer fabricated the samples by fused deposition modeling technique. The material properties were determined under tensile, compression, and three-point bending tests. The results are carried out by two methods based on experimental tests and finite element analyses that confirmed each other. The achievements provide novel insights into the determination of the adequate number of unit cells and demonstrate the energy absorption capacity of the Beta VI and Alpha VI are 23.7% and 53.9%, respectively, higher than the out-of-plane honeycomb sandwich structures.

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