Polymerized Cum posted:

Xandu posted:

Noticed this while looking on a job website for the middle east.

quote:

"While this pistol obviously wasn’t created from scratch using a 3D printer, the interesting thing is that the lower receiver — in a legal sense at least — is what actually constitutes a firearm. Without a lower receiver, the gun would not work; thus, the receiver is the actual legally-controlled part.

In short, this means that people without gun licenses — or people who have had their licenses revoked — could print their own lower receiver and build a complete, off-the-books gun."

mugrim posted:

Is the implication there that all the unspecifieds are women who don't want to have their gender known until the interview?

mugrim posted:

Is the implication there that all the unspecifieds are women who don't want to have their gender known until the interview?

For content:

A pistol with a receive made entirely of 3d printed materials that has cycled 200 rounds already. Since the receiver is what makes a modern firearm what it is, it's the qualification for many standards. Or to put it in other words:

quote:

Rather than paying experts to manufacture intricate glassware and specialized reactors, chemists of the future may be able to design and fabricate their own inexpensive reaction vessels with the push of a few buttons, according to a report in Nature Chemistry (DOI: 10.1038/nchem.1313).

An international team of researchers led by Leroy Cronin of Scotland’s University of Glasgow used a homemade three-dimensional printer—a device capable of building complicated objects layer by layer—to manufacture polymeric vessels for running chemical reactions. This relatively cheap, automated, and customizable method will make it possible for synthetic laboratories and small companies to access chemical engineering tools typically used only in large-scale industrial settings, the researchers say.

Cronin and coworkers first planned their reactor configuration with computer-assisted design (CAD) software. The resulting blueprint was then loaded into the 3-D printer, which generated the reaction vessel a layer at a time by extruding a fast-curing acetoxy silicone from the nozzles on its printhead. At pre­programmed intervals during the printing, which took anywhere from minutes to hours, the researchers added components to the silicone reactor, such as a glass window for observing reaction progress.

Chemical Reactors Made By 3-D Printing

An international team of researchers led by Leroy Cronin of the University of Glasgow has applied the up-and-coming technology of 3-D printing to chemical synthesis. The researchers built their own printer and used it to fabricate customized vessels for all manner of chemical reactions. In some cases, the reactors even participate in the reaction. This work is intended to make expensive chemical engineering tools available to everyone, the researchers say.

Using the newly manufactured vessels, the researchers synthesized new heterocyclic organic compounds and inorganic nanocluster molecules, demonstrating the reactors’ capabilities. The team also showed that their reactors could become part of the reaction: The scientists impregnated a vessel’s walls with a palladium carbon paste during printing and then used the catalyst-lined chamber to hydrogenate styrene loaded inside.

“This is a fundamental way of blurring the distinction between the reactor and the reaction,” Cronin says. “You could infinitely configure the reaction and reaction space” with this 3-D printing technique.

Among the many demonstration reactions the team ran inside its printed reactors, Cronin says his favorite is one in which the vessel’s geometry dictates a reaction’s outcome. When added in stoichiometric amounts to a large mixing chamber, the reactants 4-methoxyaniline and 5-(2-bromoethyl)phenanthridinium bromide combine to form a dihydroimidazo cationic product containing a C=N bond. A small chamber that limits the ratio of reactants at 1:1, however, mostly yields a tetrahydroimidazo isomer without the double bond.

Although the reaction vessels reported by Cronin and coworkers at this early stage are rather crude, the approach enables “an incredibly broad parameter space—including reactor design, materials, and sequence—that could be explored,” Jennifer A. Lewis says. She is a materials scientist at the University of Illinois, Urbana-Champaign, who has used 3-D printers to pattern conductive inks onto substrates. She adds that she’s gratified to see 3-D printing “employed in such a radically new way.”

Rent-A-Cop posted:

Owning one of the above will get you 10 years in jail and a $10,000 fine if you're lucky.

If you're unlucky the government will murder your family and burn down your house.

quote:

The beast above is a robotic system intended to be operated remotely in hazardous areas where network infrastructure is scarce. The robot is controlled over a WiFi network that originates on the robot and is extended by dropping the black repeater units on its back. I and seven other computer and electrical engineers built this monster as part of a senior design project at Northeastern University.

Quick Overview
Robot controlled over WiFi
40" long, 28" wide, 16" tall, about 150 lbs.
Custom-built (except for treads) out of aluminum
Range: 1 km with one on-board router and two droppable long-range repeater modules
Running time: ~12 hours
On-board webcam with microphone, night vision, pan and tilt
On-board GPS for location tracking
Custom-made remote user interface, works on any device with a web browser
Built with an EEE PC running Ubuntu, Arduino, and Node.js
Total cost: ='(

For God's sake WHY?
In the summer of 2011, we began what is known at Northeastern University as our Capstone design program. This is a senior project where we apply our computer and electrical engineering knowledge to some project. The project could be anything we wanted, and we wanted a giant loving robot. In my previous robotic project, my partner and I happened upon a few research papers and calls for proposals to build WiFi-deploying robots for use in military applications. It turns out that having ad-hoc WiFi networks can really come in handy in military operations and in disaster-affected areas, where physical network infrastructure may have been damaged.

Our group thought that the need for a WiFi deployment system was high enough to justify further exploration, and eventually we hit upon the idea that we could also use a robot to deploy a network while doing reconnaissance, and that this robot could also be controlled over the network it was deploying. This was a sufficiently interesting idea for us to start work.

The Design
In essence, this project is a robotic system for reconnaissance and WiFi network deployment. There are three main parts to it: the WiFi deployment system, the physical robot, and the robotic controls / operator interface.

WiFi Deployment System

Probably the most interesting part of this project, and unfortunately the least-developed, is the WiFi deployment system. We decided early on that it would be best to have a WiFi network as opposed to another band as this would ensure maximum compatibility with the largest number of off-the-shelf devices. This way, any consumer device could connect to our network, and we could use consumer devices in our robot's construction.

Ideally, each repeater module in our network would be tiny and able to be dropped in any order. This would give us a robust network of theoretically infinite size. Unfortunately, cheap, off-the-shelf WiFi repeater units are not available and the network configuration for the devices we did find was extremely difficult, so we decided to use consumer-grade Linksys routers loaded with the open-source dd-wrt firmware. Using dd-wrt, we were able to configure these routers as network repeaters. To lengthen their range, we used long-range antennas, power amplifiers, and 14.8V lithium-polymer batteries. Finally, we put all this in a Pelican case to protect them from the elements. These are attached to aluminum skis and fastened to the robot with a 3D-printed latch mechanism that is actuated by a solenoid.


In this scheme, each repeater repeats the on-board router's WiFi signal. Any device with a WiFi card can then connect to this repeated signal and communicate with other devices in the network, including our robot if they have the correct credentials.

The Robot
Our entire robot assembly is custom-built from scratch, as there were no reasonably-priced off-the-shelf robots that could perform the functions we needed. It was constructed out of aluminum at a hacker space called Artisan's Asylum with a healthy amount of blood and tears.


It is a little more than 3 feet long, 2 feet wide, and weighs about 150 pounds. It has carried at least a 200 pound person on its back with no complaint. It can go roughly 8-10 mph at top speed. We suspect that with a more powerful motor controller, we would be able to climb a set of stairs, thanks in large part to its impeccably-designed center-of-gravity. It did not require any welding, only tapping, to build. In short, this thing is indestructible (except, like the Wicked Witch of the West, when exposed to water).

Note carefully that nowhere above do I say anything about the presence of mechanical engineers in our group. This is because there were none. Our entire robot was effected almost single-handedly by my previous partner in crime who is responsible for the wooden robot. In several months he accomplished the following: hundreds of iterations of 3D design in CAD software, built a full-size wooden prototype as a proof-of-concept, learned to work with metal, and finally built the exact physical manifestation of his 3D model in metal using a CNC machine and waterjet cutter, without ever having done something like this before. He is an amazing specimen that is now helping out with a 14-foot rideable hexapod. I tremble to think what he will work on next.


One really neat thing my partner custom-designed and built is a mechanical device called a tensioner. In its normal form, this thing takes up slack in something such as a chain (like on a bicycle). In this case, it gives tension to our robot's treads. When our robot runs over an obstacle the treads deform, causing them to tighten around the sprockets and load-bearing wheels. With this tensioner, most of that squeezing force goes into squeezing the spring in the direction indicated by the arrow. This helps the treads stay firmly on our robot, just where they should be.

As for the electrical components, our robot is powered by a battery of nine 14.8V Lithium Polymer, er, batteries for a total of 45Ah. These are stepped down to 12V using a DC-to-DC converter in order to power both our on-board peripherals and 12V brushed DC motors. We custom-built an H-Bridge for our motor controls (quite a project!), but this proved to be the source of a lot of issues. We watched many times as the magic smoke left our electronic components from the massive current our motors drew on startup. In the future, we would probably look more into an off-the-shelf motor driver, despite their expense. The H-bridge is attached to an Arduino that outputs PWM signals. The Arduino is attached via serial port to the brains of the robot, our EEE PC (which is snuggled lovingly inside a Pelican box).

Software / User Interface

Since our hardware is made up of heterogeneous components cobbled together, we needed software to let all these things talk to each other. That was my job. As the only person with extensive software experience, I had the privilege of writing all the code for this project. This was a great excuse to play around with Node.js and learn JavaScript better.

Here are all the things you can do from the web interface:

Control the robot's speed and direction using your keyboard's arrow buttons or the web buttons
View live webcam footage and control it (including pan/tilt, night vision, and audio)
Drop WiFi repeater units to extend robot's range
View robot and repeater positions in real-time on a map using on-board GPS
View repeater signal strengths in real-time
View the status of the interface's connection to the robot
Begin replaying the robot's movements backward if it loses its WiFi connection
Run over lots of poo poo
So how does this thing work? In order to speed up development time and reduce development complexity, I volunteered my EEE PC running Ubuntu Linux to be the brains of our robot. With its solid-state drive and small form factor, it proved to be a good candidate to stow on-board the robot. From this computer, we ran a node.js web server that served the user interface and communicated with our on-board peripherals.

Given my previous experience in web development, a web interface was the only thing I was qualified to make. Luckily, a web interface has the advantage of working on pretty much any device with a web browser (including laptops, tablets, and phones), which means no specialized hardware is needed to control our robot. And given the recent development of websockets, we were able to control our robot in real-time from a web browser. Also, given that our robot is processing a wide variety of data asynchronously, an event-driven model makes a lot of sense, and this is exactly what node.js provides.

I find it highly amusing that this robot is written almost entirely in JavaScript. To see for yourself view the open source code on Github.

Conclusion
We are all very proud of our accomplishment in building this robot. It performs near flawlessly exactly as we intended and is utterly badass.

ekuNNN posted:

ekuNNN posted:

Invalido posted:

I expect we will see all sorts of creativity from amateur drone enthusiasts.

mugrim posted:

Speaking of...

Fried Chicken posted:

For those that don't know, this is an auto-sear. It is what lets you convert a semi-auto AR-15 into a fully automatic weapon.

Zedsdeadbaby posted:

That little bit of metal is fascinating. I was just reading into that now after seeing your post. That part quoted is what turns a semi-automatic AR-15 into a machine gun - but the catch is, in the USA, machine guns have been banned for civilian use, as well as the manufacture and imports of such machine guns, since 1986 by Ronald Reagan. That makes this seemingly insignificant hunk of metal incredibly expensive, seeing as nobody is allowed to manufacture or fit one made after that year.

So this man here is why there are hardly any automatic AR15s around. A sensible bit of gun legislation perhaps?

LP97S posted:

Reagan has historically been pro gun control, while governor of California he signed the Mulford Act, which banned the transporting of loaded weapons on person or in one's vehicle in public spaces. This was done primarily to curb the Black Panthers who famously protested it.

Mans posted:

Just so you know, that picture is from the Bastiat Institute. They're not saying that the proletariat is being skinned alive just to see all his work sucked by the owners, they're saying that taxes = slavery.

Zedsdeadbaby posted:

That little bit of metal is fascinating. I was just reading into that now after seeing your post. That part quoted is what turns a semi-automatic AR-15 into a machine gun - but the catch is, in the USA, machine guns have been banned for civilian use, as well as the manufacture and imports of such machine guns, since 1986 by Ronald Reagan. That makes this seemingly insignificant hunk of metal incredibly expensive, seeing as nobody is allowed to manufacture or fit one made after that year.

ekuNNN posted:

It sucks when you're tricked into agreeing with a libertarian

Quick, I must restore my left-cred with some other work related pics:

Saint Sputnik posted:

Dr. Cogwerks posted:

toryproblems.txt

Highspeeddub posted:

If there is one thing I do appreciate about the Brits, it's their ability to hold a grudge.



Don't worry, all the thinking people left in the states hate him too and wish his wife's dressage horse would trample him to death in a freak accident.

ElMaligno posted:

Jeremy Clarkson is the best troll, in fact Top Gear just loves to troll the gently caress out of people.

quote:

The streets were mostly empty. I stopped to photograph some settlers marking the Jewish holiday of Purim. They were passing around a bottle of wine, toasting the holiday, nothing out of the ordinary. I noticed a Palestinian woman walking along the shut-down stores. A group of settlers were walking in the middle of the street in the opposite direction when one of them took a step towards her. I instinctually raised the camera.

She didn’t scream or stop, she hurried up the street and vanished around the corner. I was left angered and saddened — as if the wine hit me.

Tiler Kiwi posted:

I finally have something to contribute.



http://www.kboi2.com/news/local/billboard-James-Holmes-Idaho-President-Obama-kboi-164065466.html

Tiler Kiwi posted:

I finally have something to contribute.



http://www.kboi2.com/news/local/billboard-James-Holmes-Idaho-President-Obama-kboi-164065466.html