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NeoPixel Ring with snap for 3D design #3DThursday #3DPrinting

scientiffic shares:

A modification of @enauman’s Neopixel Ring that has a snap for attaching a custom 3D-printed design.

Instructable

A full Instructable on how to use this design in the context of a Butterfly model designed by @enauman can be found here: http://www.instructables.com/id/3D-Printed-NeoPixel-Ring-Butterfly-With-Tinkercad/?linkId=51899198

download the files on: https://www.thingiverse.com/thing:2954923

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Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!

The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

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Pentasynth: A homebuilt pentatonic keyboard and synth

Thanks for sending this in Mitch! Via Random Project Lab

This is part two (see part one) of a post on a custom-built Arduino-based synthesizer and keyboard called “Pentasynth”. Pentasynth uses a keyboard based on a five note pentatonic scale, so it’s easy to play for people with limited background in music (such as young kids) and encourages experimentation and improvisation. Pentasynth creates a user-selectable accompaniment including different drum patterns, bass lines and chord progressions and allows the user to play a pentatonic melody line over the top. Under the hood, Pentasynth runs on an Adafruit Metro Mini (using the same ATmega328 microcontroller as the Arduino Uno) and generates three channel audio (two square-wave tones and one pseudo-random noise drum beat), which is passed through and onboard amplifier and speaker, while simultaneously passing all outputs as MIDI messages via the USB for either a lo-fi or hi-fi audio experience. Pentasynth has controls for volume, tempo and selection of different accompaniment patterns. The keys and case components are 3D printed, with the main case panelling carved from clear acrylic using Carvey. Custom PCBs containing switches for detection of key presses were also carved on Carvey.

In the previous post, I discussed the hardware development of the keyboard including 3D printed keys and CNCed case and key switch PCBs, and the use of a wavetable synth for audio. I wasn’t that happy with the audio quality from the wavetable synth, so I re-wrote my own system using hardware PWM square-waves for audio, with a bit of re-jigging to add MIDI output. I’ll also discuss the electronics in a bit more details and the code running on the Arduino.

The ATmega328 has three hardware timers that can each be used to drive interrupt routines or run a hardware Pulse Width Modulation (PWM) signal. Since I wanted to keep the main program on the microcontroller free to managing key and control inputs and running an accompaniment system, the hardware timers were the only way to generate audio signals. By default, two of these timers (Timer 1 and 2) are unused, and the other (Timer 0) is set to run at 1kHz and controls functions such as millis() and delay(): any change in this frequency would mess with these. I’ve setup Timer 2 to run a square-wave output based on the note pressed on the keyboard and Timer 1 to run a square-wave from an accompaniment baseline. In order to get a pseudo random noise signal for a drum beat, I’ve piggy-backed an interrupt routine on the existing 1kHz to generate a pseudo random square-wave (i.e. randomly ordered series of LOW/HIGH) using a Galois linear feedback shift register (see this nifty little post). The random signal switched at 1kHz sounds a bit like a snare or open high-hat, so makes for a decent (lo-fi) beat.

See more!

Electronics

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TU Wien Researchers Use 3D Printed Plastic Screens to Perfectly Shape Terahertz Beams

Terahertz radiation [Image: Tech-FAQ]

The terahertz spectrum is tucked away between more commonly known electromagnetic wavelengths, like infrared and microwave. This spectrum, and the radiation wavelengths it emits, is still a decently new field of study, and researchers have learned that terahertz radiation (THz) is chock full of information that can add value to applications in imaging and communications; THz is often used today for material analysis in laboratories, as well as in airport security checkpoints. Its wavelength, in the millimeter range, is far larger than one of visible light, and its beams can only be manipulated with special techniques.

Switching from its more recent focus on 3D printing materials, researchers at the Technical University of Vienna (TU Wien) in Austria have been studying ways to shape the perfect terahertz beam, and have succeeded thanks to a 3D printed, precisely calculated plastic screen.

The TU Wien research team can use this simple 3D printed screen to precisely shape terahertz beams into desired shapes.

“Normal plastic is transparent for terahertz beams, in a similar way as glass is for visible light. However, terahertz waves slow down a little when they pass through plastic,” explained Professor Andrei Pimenov from TU Wien’s Institute of Solid State Physics. “This means that the crests and troughs of the beam become a little displaced – we call that phase shifting.”

Think of a glass optical lens, with a middle thicker than the edge. When a beam of light hits the middle of the lens, it will spend more time in the glass than a second beam that hits the edge at the same time. This causes the middle light beam to be more phase delayed than the one on the edge, which then changes the beam’s shape – for instance, a wider beam of light can focus on a single point. The TU Wien researchers used this same type of phase shifting to shape terahertz beams, though they’re far from done with this line of study.

“We didn’t just want to map a wide beam to a point,” said Jan Gosporadič, a PhD student on Professor Pimenov’s team. “Our goal was to be able to bring any beam into any shape.”

The researchers accomplished just that by inserting a precisely adapted, 3D printed plastic screen, with a diameter of only a few centimeters, into the beam. They have to adjust the thickness of the screen, from 0 to 4 mm, during the process in order to deflect different areas of the beam in a controlled manner. Then, they will end up with the desired image or shape at the end.

“The process is amazingly simple. You don’t even need a 3D printer with an especially high resolution,” Professor Pimenov said. “If the precision of the structure is significantly better than the wavelength of the radiation used, then it’s enough – this is no problem for terahertz radiation with a 2mm wavelength.”

Jan Gospodarič and Professor Andrei Pimenov in the lab.

The team recently published a paper on their work, titled “3D-printed phase waveplates for THz beam shaping,” in Applied Physics Letters; co-authors include Gosporadič, A. Kuzmenko, Anna Pimenov, C. Huber and D. Suess from the University of Vienna, S. Rotter, and Professor Pimenov.

The abstract reads, “The advancement of 3D-printing opens up a new way of constructing affordable custom terahertz (THz) components due to suitable printing resolution and THz transparency of polymer materials. We present a way of calculating, designing, and fabricating a THz waveplate that phase-modulates an incident THz beam (λ0 = 2.14 mm) in order to create a predefined intensity profile of the optical wavefront on a distant image plane. Our calculations were performed for two distinct target intensities with the use of a modified Gerchberg-Saxton algorithm. The resulting phase-modulating profiles were used to model the polylactide elements, which were printed out with a commercially available 3D-printer. The results were tested in a THz experimental setup equipped with a scanning option, and they showed good agreement with theoretical predictions.”

When screens are inserted into the beam, specific patterns emerge: a cross or the TU Wien logo.

Researchers developed a special calculation method to achieve the desired design for their 3D printed screens. To show how many possible designs have been opened up through their new THz beam shaping method, the TU Wien research team 3D printed several different screens, including an option that shapes a wide beam into the easily recognizable shape of the university’s logo.

Professor Pimenov said, “This shows that there are hardly any geometric limits to the technology. Our method is relatively easy to apply, which leads us to believe that the technology will be rapidly introduced for use in many areas and that the terahertz technology that is currently emerging will make it a bit more precise and versatile.”

Discuss this story, and other 3D printing topics, at 3DPrintBoard.com, or share your thoughts below.

[Source/Images: TU Wien]

 

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Student Uses 3D Printing to Develop Vocal Prosthetic

Nikita Dubrovsky

Cancer of the larynx is treatable, but it sometimes requires removing the larynx altogether, leaving the patient unable to speak. There are, however, vocal prostheses that can be implanted to restore the patient’s speech. Unfortunately, these prostheses are expensive and tend to need frequent replacement. So South Ural State University student Nikita Dubrovsky is working on an alternative.

“Everywhere in the world, the method being chosen for vocal rehabilitation of the patients who underwent laryngectomy is the voice prosthetic care,” said Dubrovsky. “Most often abroad-manufactured apparatus are used which allow patients to recover their voice. But the big minus here is that such an apparatus is due for replacement after approximately just one year. Imported prostheses are quite expensive, so we decided to come up with our own development, which will feature similar technical characteristics, but will be much cheaper.”

Vocal prostheses first began being used in 1980. A shunt is placed between the trachea and upper esophagus, and a valve is implanted into the opening. This valve allows for the exhalation of air from the trachea to the esophagus, which creates vibration in the walls of the esophagus and the lower pharynx, generating sound. These valves have more than one drawback, however.

“The abroad-manufactured prostheses mostly use plastic, which is very inconvenient because it’s hard,” explained Dubrovsky. “We’re planning on using food silicones, which will make the prosthesis softer, and patients will less suffer from pain. The forms for drip moulding, which we will be filling with silicone, will be manufactured using 3D printing.”

A 3D model of the vocal prosthetic was created, and scientists at the SUSU Research Center for Sport Science have used SLA 3D printing to create a prototype, which will be sent for clinical testing at the Chelyabinsk Regional Center for Oncology and Nuclear Medicine.

“Unfortunately, when we were working with 3D printing, we faced damages that occurred in the drip-moulding tank in the process of the model creation,” said Dubrovsky. “Moreover, such process of production may take 12 to 24 hours, which is a very long time. Since 3D printing turned to be not that accurate, we will probably have to give it up in the future and turn to lathe operators instead, as they are in command of high-accuracy equipment. But first we need to improve our computer model.”

Dubrovsky and his fellow researchers will continue work on the implant as Dubrovsky continues work towards his Master’s degree; he just graduated with a Bachelor’s in Physical Education. They will work on finding food-grade silicone of optimum hardness for patient comfort.

Dubrovsky’s work is potentially good news for the future of patients who require larynx removal; unfortunately, this week also brings some bad news for Italian surgeon Paolo Macchiarini and his patients. Macchiarini published a paper in 2011 in the medical journal The Lancet regarding an artificial windpipe he had created that was coated with the patient’s own stem cells, which would then develop into mature tracheal cells that would not be rejected by the patient’s body. It sounds like a groundbreaking development in bioprinting, but it turns out that the procedure was worse than ineffective.

Macchiarini and colleagues performed the procedure on a total of eight patients, seven of whom died. The surgeons lost track of the eighth. Macchiarini was associated with the Karolinska Institute, which awards the Nobel Prize in medicine every year. In 2014, several surgeons at Karolinska filed a complaint alleging that Macchiarini had downplayed the risks of the procedure, and that it had been carried out on at least one patient who had not been critically ill at the time.

Paolo Macchiarini [Image: Lorenzo Galassi/AP]

Recently, the new President of the Karolinska Institute, Ole Petter Ottersen, requested that The Lancet retract two papers published by Macchiarini, and the journal obliged, as explained in a recent editorial. The Lancet is a prestigious medical journal that only publishes work after extensive peer review, so such a retraction is extremely rare.

“No ethical permit had been obtained for the underlying research,” said Ottersen. “The research was carried out without sufficient support by preclinical data, and the paper presents its data in a way that is unduly positive and uncritical. The clinical findings reported are not supported by source data.”

Macchiarini and his co-authors were found guilty of misconduct, and two members of the Nobel medicine prize assembly were forced to step down.

Discuss these and other 3D printing topics at 3DPrintBoard.com or share your thoughts below. 

[Sources: South Ural State University, CTV News / Images: Viktoria Matveichuk unless otherwise noted]

 

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Researchers Develop Peat 3D Printing Construction Mixture

Not only has construction 3D printing gotten quite a boost in the recent year, but fringe, organic building components within the field have seen a surge as well. From bacteria to hemp, construction printing is finding strange new ground (sometimes literally). Now, researchers are toying with the use of peat 3D printing mixture for construction […]

The post Researchers Develop Peat 3D Printing Construction Mixture appeared first on 3D Printing.

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Virtual Foundry: desktop 3D metal printing, today

The Virtual Foundry, llc. is first to market with an inexpensive system for desktop 3D metal printing. The strategy leverages existing 3D printers and existing metal processing equipment to dramatically reduce the cost of metal 3D printing. The idea is simple, Filamet™ the core product patented by The Virtual Foundry, makes any existing 3D printer […]
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FIT Additive Manufacturing Group teams up to save the reefs

Boston Ceramics, a member of the FIT Additive Manufacturing Group, has released an update of its work for an initiative using 3D printing to help save the world’s coral reefs. Building upon several years research into the behavior and breeding of coral by international non-profit organization SECORE International, Boston Ceramics is helping to provide objects […]
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Senvol Joins National Armaments Consortium

The National Armaments Consortium (NAC) is the industry and academia component of the Department of Defense Ordnance Technology Consortium (DOTC), and serves as the primary organization enabling the US government, industry and academia to deliver rapid armaments innovation for the security of the United States. Originally, DOTC was commissioned by the Under Secretary of Defense for Acquisition, Technology and Logistics as a US Department of Defense (DoD) initiative. The goal of the consortium was to facilitate collaborative government, industry and academic ordnance technology development and prototyping.

Nowadays, the mission of DOTC is to enable the DoD Ordnance community to work collaboratively in RDT&E of prototype solutions to advance and transition ordnance systems, subsystems and component technologies.

The newest member of the NAC is Senvol, a company that provides data to help companies implement additive manufacturing. Its services include the Senvol Database, a comprehensive database of industrial additive manufacturing machines and materials; the Senvol API, which provides raw access to the Senvol Database; and the Senvol Indexes, pedigreed data sets for additive manufacturing material characterization. Senvol also offers the Senvol SOP, a standard operating procedure that details how to generate pedigreed additive manufacturing data, and the Senvol ML, a software suite that helps companies quickly characterize or qualify additive manufacturing materials and processes.

“We’re pleased to join the National Armaments Consortium and look forward to contributing to the advancement of armament technologies in the United States,” said Senvol President Zach Simkin. “Senvol is the leader in data for additive manufacturing, and we’re eager to support the consortium’s mission through the use of additive manufacturing analytics.”

Government participants in DOTC include US Army AMRDEC, Naval Surface Warfare Centers, Defense Advanced Research Projects Agency (DARPA), and Naval Air Systems Command. Technological areas of focus for DOTC include Ammunition, Demilitarization, Directed Energy Warfare, Enabling Technologies, Energetic Materials, Fuzes, Joint Insensitive Munitions, Protection & Survivability, Rockets, Missiles and Bombs, Sensors & Sensor Systems, Warheads Lethal Mechanisms, and Weapon Systems.

Recently, Senvol began developing additive manufacturing software for the US Office of Naval Research, and its membership in the NAC further advances the company’s status as a provider of AM data services to national security interests, not just private companies. Senvol is a Gold Member of America Makes, and its executives have been appointed to multiple leadership positions including as members of SME’s Additive Manufacturing Advisory Board, the ASTM International F42 Committee on Additive Manufacturing Technologies, ASME’s Technical Advisory Panel for additive manufacturing, and also as Vice Chair of the Data Management Committee for SAE.

NYC-based Senvol’s products and services have been used by a wide variety of Fortune 500 companies and government agencies in a range of industries such as aerospace, automotive, oil and gas, and consumer products.

In other weaponry news, you may recall Cody Wilson, who has been embroiled in a legal battle ever since he first published the open source files for his 3D printed handgun on the Internet. He was ordered by the State Department to remove the files, which he did, but then filed a lawsuit against the State Department claiming that it was violating his right to free speech, among other rights. After a long, drawn-out battle, it looked as though Wilson was going to lose his case.

However, things took a turn in his favor a couple of months ago when the Department of Justice offered Wilson a settlement. Confirmed in court documents this month, the settlement promises to change the export control rules surrounding any firearm below .50 caliber, with exceptions for fully automatic weapons and rare gun designs that use caseless ammunition, and hand over their regulation to the Commerce Department, giving Wilson freedom to publish data about his gun designs anywhere online. You can learn more about the case with in-depth coverage from Wired.

Discuss these and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.