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Let’s Bring Back the Age of Automatons

พุธ, 03/28/2018 - 22:00

Long before the concept of A.I., as we know it today existed, humans started building machines that seemed to move and even think by a will of their own. For decades we have been building automatons, self-operating machines, designed to resemble humans and animals. Causing the designer to break down human and animal movements, behaviors, and even speech (by way of bellows and air tubes) into predetermined sequential actions.

[Greg Zumwalt] created what he calls a hummingbird themed automaton inspired by his wife’s love of watching hummingbirds gather near their home. His 3D printed and assembled hummingbird automaton moves almost as fluid as its organic counterpart. The design is simple yet created from an impressive number of 97 printed parts printed from 38 unique designs which he includes in his Instructable. Other than meticulous assembly design, the fluid motion lends itself to a process of test fitting, trimming, and sanding all printed parts. Plus adding petroleum jelly as lubrication to the build’s moving parts. Along with the print files, [Greg Zumwalt] also gives you the print settings needed to recreate this precision build and a parts list accounting for all the multiple prints needed for each design.

[Greg] has been on a roll lately.  Check out his air-powered engine, or what may possibly be the simplest 3D-printed robot ever.

To keep putting your 3D printer to good use check out this 3D printed water droplet simulation automaton. If you want to learn more about the history of automata, head over to this post we wrote up about a well-known automaton called the “Draughtsman-Writer” created by Swiss mechanician and clockmaker, Henri Maillardet.

The Essential List of 3D Printer Accessories

พุธ, 03/28/2018 - 21:01

You’ve acquired your first 3D printer and are giddy with excitement. But like all new additive manufacturing adventurers, the more you do with your printer the more questions arise. Don’t worry, we’ve got your back.

Getting the most out of your time with a new 3D printer has a lot to do with the tools and accessories on hand and what you do with them. Let’s take a look at a few of the accessories that should accompany every 3D printer, be it in your home, school, or hackerspace. There’s already enough potential aggravation when it comes to 3D printing, the goal here is to ensure you won’t be without a tool or supply when you need it the most.

Previously we talked about what one should do after getting their own 3D printer to ensure, in so much as can be possible with this sort of thing, long term success. If you haven’t seen that article yet, make sure you add it to your reading list. The regular maintenance and calibration that is unique to 3D printing was covered, as was the need for the operator to personally hone their own skills.

Filament: Avoiding Dragons and Building Your Stock

OK, so obviously you need filament for your 3D printer. But which filament? Personally, I’d suggest you get a few different brands early on so you can see what works for you. As tempting as it might be, don’t just buy the cheapest roll of PLA on Amazon. There be dragons.

Hatchbox brand filament is always a good bet

Depending on what you want to do, you may also want to check out some of the different infused PLAs. For example, wood-fill PLA tends to be much easier to sand than regular PLA, so I like to use it for larger prints which I want to smooth. Just be aware that infused filaments have a tendency to erode your printer’s nozzle pretty quickly.

Now I’ll save you some trouble and tell you what you absolutely don’t need in 2018, and that’s ABS. At the risk of starting a war in the comments, there’s no good reason to still be using ABS anymore. Not only is it unpleasant to work with and potentially harmful to your health (depending on whose research you read), but what little strength advantage it had has largely become moot with newer PLA formulations. If you need strength or temperature tolerance beyond what PLA is capable, save yourself the headache and check out PETG or nylon.

The only possible reason you might still want to use ABS anymore is to do acetone vapor smoothing. But unless you’ve got some assembly line knocking out little statues or art pieces that need to be rapidly smoothed without concern for surface details or mechanical tolerances, you’d be better off just sucking it up and grabbing some sand paper.

Digital Calipers Pay for Themselves

If you’re going to take 3D printing seriously, you need a digital caliper. You can use it to check filament diameter for extruder fine tuning, to verify the dimensions of a calibration print, or to take accurate measurements of a part you want to replicate in 3D. You could get an analog one if you want to pretend you’re Wernher von Braun or something, but the ease of use and effortless accuracy afforded by the most basic of digital calipers just can’t be beat.

Don’t be fooled into buying some Mitutoyo digital caliper that costs nearly as much as an entry-level 3D printer either; you won’t need that kind of accuracy when working with extruded plastic. Even cheap calipers can muster up an accuracy of 0.1 mm and enough repeatability for our purposes. A basic six inch digital caliper with a hard storage case shouldn’t cost you more than $20 USD, and will pay for itself many times over.

Print Removal Tool

As a general rule, a part needs to be strongly adhered to the bed for successful printing. A big piece stuck down properly to the bed can easily be so firmly attached that you could lift the whole printer up by it. That’s exactly what you want while the print is ongoing, but when the print is over it can be a problem.

Image Credit: Gizmo Dorks

You don’t want to just yank the thing off; doing so could damage the printer or break your completed part. You also want to be very careful of using a knife to get under the print and pry it free. It sounds reasonable enough, and surely every 3D printer owner is guilty of doing it on occasion, but there’s a very real risk of slipping and cutting yourself. Even if you manage to get your print off the bed without opening a vein, there’s still a high chance of gouging or scratching the bed because you have to hold the knife at an angle.

To avoid hurting yourself or your printer, you should spend the couple of dollars on a proper print removal tool. Generally speaking these are as thin as a knife blade, but without the sharp edge. They’re also usually angled in such a way that you can hold the handle parallel to the bed. These two design elements mean that there’s a much lower chance of damaging your bed, as the tool won’t be coming in at an angle.

Personally I use a print removal tool by Gizmo Dorks, and I’ve been very happy with it. After two years or so of regular use, the leading edge of the blade has a few nicks in it from some of the more stubborn parts I’ve had to pull up, but nothing serious. For less than $10 USD, you can’t go wrong.

Isopropyl Alcohol Cleans Between Prints

A dousing of isopropyl alcohol will remove waxes, oils, and other contaminates from the bed which can greatly improve print adhesion. No matter what you’ve got on your bed, from 3M Blue painter’s tape to PEI, you should be wiping it down as often as every print to help prevent curling and warping.

Some people like to use alcohol prep pads, the kind of thing you’ll find in a first aid kit. This isn’t a bad idea, especially given how cheap they are. But personally I keep a small mister bottle of alcohol and some cotton balls in a box near the printer. Before a print I’ll give the bed a good spray, wipe up with one of the cotton balls, and toss it in the trash. You could also use a microfiber cloth or something along those lines, but you’ll need to make sure it’s getting regularly washed to keep from contaminating the surface.

Fire Protection

The risk of fire, especially with some of the cheaper overseas printers that are now flooding the market, is very real. Though even high end machines aren’t completely immune, as we’ve unfortunately seen in the past. You should have a smoke alarm located near the printer. They are less than $10 USD at the big box home improvement stores, and well worth every penny if it goes off during an overnight print that went awry.

In the past we’ve talked about elaborate fire suppression systems for 3D printers, but a basic “ABC” type fire extinguisher located in the same room as the printer would be more than sufficient if you want to have some defense in the worst case scenario. Again, these are cheap and readily available for a reason.

What Else?

These are a few things which I believe every 3D printer owner should have, they’ve served me well for years and are what I find myself relying on most frequently. But surely there are others out there which are worth mentioning. What would the readers of Hackaday consider to be “Must Haves” when it comes to desktop 3D printing? Better yet, what would you say is something new 3D printer owners should avoid wasting their money on?

The End of the Candy Rainbow

พุธ, 03/28/2018 - 18:00

About a decade ago [Windell Oskay] and [Lenore Edman] spun out of Evil Mad Scientist Laboratories to work on CandyFab, an inexpensive 3D printer using sugar as its medium. Wondering what happened to CandyFab? It’s been nearly that long since we last wrote about their work and Maker technology has moved on. 3D printers run the gamut from very inexpensive to production ready. The CandyFab project and nascent company is now shuttered, but there is a epilogue with some interesting lessons.

The CandyFab 6000

First of all, the saga of the CandyFab series of printers (above on the same page) is worth a read. Some of what these machines were capable of is still quite impressive by modern standards. Sure your Monoprice Mini Delta may be easy to use, fully assembled, functional when you take it out of the box, and quiet. But what if you need to print something up to 8.5″ x 11″ x 17″? The CandyFab 5000 can do that. Or even a humongous 24″ x 13.5″ x 9″? The CandyFab 4000 can do it, and for a measly $37 (if you printed a solid cube exactly the size of the build volume)! Sugar may have downsides but it’s still a pretty clever medium for some uses.

CandyFab credits the rise of MakerBot coupled with the complexity of iterating from a pile of “surplus junk” (their words) to something kitable. Reading their post-mortem brings to mind familiar problems from today’s hardware world. A spike of fantastic early publicity lead to the need to handle press while rapidly iterating from the aforementioned surplus parts to a reliable and manufacturable design. Then the complexity of balancing a day job and other side projects with the prospect of CandyFab as a business. Ultimately the need for the project in the first place (accessible inexpensive 3D printers) was alleviated by the market and the project came to a graceful close.

Give the post a read, we’re sure you’ll learn something!

Car Revival According to Tesla

พุธ, 03/28/2018 - 15:00

Frankencars are built from the parts of several cars to make one usable vehicle. [Jim Belosic] has crossed the (finish) line with his Teslonda. In the most basic sense, it is the body of a Honda Accord on top of the drive train of a Tesla Model S. The 1981 Honda was the make and model of his first car, but it wasn’t getting driven. Rather than sell it, he decided to give it a new life with electricity, just like Victor Frankenstein.

In accord with Frankenstein’s monster, this car has unbelievable strength. [Jim] estimates the horsepower increases by a factor of ten over the gas engine. The California-emissions original generates between forty and fifty horsepower while his best guess places the horsepower over five-hundred. At this point, the Honda body is just holding on for dear life. Once all the safety items, like seatbelts, are installed, the driver and passengers will be holding on for the same reason.

This kind of build excites us because it takes something old, and something modern, and marries the two to make something in a class of its own. And we hate to see usable parts sitting idle.

Without a body, this electric car scoots around with its driver all day, and this Honda doesn’t even need the driver inside.

3D Printed ESP8266 Programming Jig

พุธ, 03/28/2018 - 12:00

The various development boards such as the NodeMCU or Wemos D1 make working with the ESP8266 an absolute breeze. If they have a downside, it is that they are larger than the bare ESP2866, and of course cost a bit more. Just as with the Arduino, once you have the wiring sorted out and the code more or less finalized, your best bet is to ditch the unnecessary support hardware and use the bare module to save space and money in your final design.

The design took a few revisions to get right

Unfortunately, the ESP8266 form factor isn’t terribly forgiving when it comes time for hooking up a programmer. Rather than having to solder a serial adapter to the chip to flash it, [Ryan] came up with a slick 3D printed programming jig that uses pogo pins. If you have to program these boards in bulk, a jig like this can save a massive amount of time and aggravation.

Beyond the 3D printed holder for the pogo pins, this programmer uses a FTDI USB-to-serial adapter, a couple passive components to smooth out the power going into the chip, and a couple buttons.

In the video after the break, [Ryan] walks through the many iterations it took to get the 3D printed aspect of the jig worked out. The design went through a few rather large revisions, including one that fundamentally changed the whole form factor. Even with the jig now working, he mentions that he might circle back around and try it from a different angle.

Programming jigs are a staple of electronics manufacturing, and we’ve covered quite a few that have helped transformed a proof of concept into a small scale production runs.

Forth Version 1 Runs Again

พุธ, 03/28/2018 - 09:00

Some people love Forth and some people hate it. However, you usually think of Forth as something running on a little computer such as an 8-bit microcomputer. When [Chuck Moore] developed the system back in the 1960s though, it ran on an IBM 1130. [Carl Claunch] took a scanned listing of the original code and got it running once again.

There are actually a few blog posts with details. Luckily, Forth is pretty simple — especially the core parts. However, there are a lot of differences from a modern Forth. The most obvious is that the dot keyword starts a definition and does not print the top of stack. However, internal details are different too — the system, for example, stores characters in packed EBCDIC — an ASCII-like code used by IBM computers.

Oddly, [Moore] used Forth to write code that would allow the big computer to help design carpets, although the project was ultimately unsuccessful. However, the language, which grew from [Moore’s] private card deck library, was much easier to use than the machine’s preferred FORTRAN.

The group working on this has released the original scans and promises a machine-readable version soon. Don’t have an IBM 1130 to run it on? Sure you do.

If you want something more modern and smaller, you have a choice of Hackaday-approved projects. For instance, Mecrisp-Stellaris Forth on an ARM. Or, go cloud, and run it in your browser.

Terrible RC Transmitter Made Less Terrible

พุธ, 03/28/2018 - 06:00

It should probably go without saying that we’ve got nothing against the occasional bout of elaborate troubleshooting and repair, in fact it’s one of the most common things we cover here. As it turns out, people aren’t overly fond of being fleeced, and there are a lot of smart people out there who will put a lot of work in to keep from having to toss a favorite piece of gear into the trash. We can’t fault them for that.

But we have to say, we generally don’t see those kind of elaborate repairs for something brand new. Unfortunately, that’s exactly what [Marek Baczynski] had to do when trying to review the new iRangeX transmitter for his YouTube channel “dronelab”. He found a transmitter that was so poorly designed and constructed that he had to address a laundry list of issues to make the thing halfway tolerable. As you might expect, he’s not suggesting anyone go run and pick this one up.

The biggest problem is a fundamental flaw with how the gimbals are constructed. Due to poorly mated surfaces between the potentiometer and the stick itself, the accuracy of the controller is very low. The potentiometers don’t even return to zero when the sticks are released. Some tape was used to tighten up the connection and make the controller usable, but such poor tolerances are hard to forgive when accurate control is essentially the whole point of the device.

The other issues took a bit more debugging to figure out. The TX made an absolutely terrible screeching sound when turned on, but [Marek] was sure he was hearing a little bit of melody under the din. Putting the signal through the oscilloscope, he was able to confirm his suspicions. As it turns out, the buzzer used in the TX has a built in tone generator that was overriding the intended melody. Switching it out for a basic buzzer fixed the issue. Similarly, an issue where the radio wouldn’t turn on if it was recently turned off was tracked back to a resistor of the wrong value. Putting a higher valued resistor in its place sorted that out as well.

It’s hard to imagine how this device made it out of the factory with so many wrong or unsuitable components, but here we are. Not that this would be acceptable at any price point, but as [Marek] points out in the video, it isn’t as if this radio is even all that cheap. For nearly $90 USD, it doesn’t seem unreasonable to expect something that actually works.

This isn’t the first time he’s put “cheap” RC hardware through the wringer. We recently covered his efforts to quantify latency in different transmitters. As the RC transmitter world gets increasingly competitive, detailed analysis like these help separate the real gear from the toys.

“Attempt” at Wristwatch is a Solid Success

พุธ, 03/28/2018 - 03:00

Sometimes silence is the best compliment to a DIY project, and that doesn’t just apply to homemade lockjaw toffee. When a watch is so well-made that it looks like one from a jewelry store, it is easy to keep quiet. [ColinMerkel] took many pictures of his fourth wristwatch attempt but “attempt” is his word because we call this a success. This time around he didn’t forget the crown for adjusting the time so all the pieces were in place.

His second “attempt” at wristwatch making was featured here and it had a classical elegance. Here, the proverbial game has been stepped up. Instead of using stock steel, the body is constructed of 303 stainless steel. The watch dial will definitely draw compliments if its DIY nature is revealed, which is equally mathematical and charming. Pictures of this process were enough to convey the build without words which is always a bonus if you only want a quick look or English isn’t your first choice for language.

Not only is [Colin] an upstanding horologist, he has a reputation with aftermarket door security and a looping guitar pedal.

Neon Display for a Vacuum Tube Calculator

พุธ, 03/28/2018 - 01:30

When it comes to vintage displays, everyone gravitates to Nixies. These tubes look great, but you’re dealing with a certain aesthetic with these vintage numeric tubes. There is another option. For his Hackaday Prize entry, [castvee8] is making seven-segment displays out of vintage neon lamps. It looks great, and it’s the basis of an all-vacuum tube calculator.

The core of this build are a few tiny NE-2 neon bulbs. These are the same type of bulbs you’ll find in old indicators, and require somewhere around 100 volts to fire. These bulbs are then installed in a 3D-printed frame, giving [castvee] a real seven-segment display, a plus or minus sign, and an equals sign. It’s the beginnings of a calculator, right there.

One of the recent updates to this project is controlling these displays with modern logic. That might be a bit of a misnomer, because [castvee] is using diode steering and a TTL chip to cycle through the numbers 1 to 4. The actual code to do this is running on a microcontroller, though, so that might get a pass. This is just a test, though, and the real project looks to be an all-vacuum calculator. The project is still in its early stages, but there are still months to go in the Hackaday Prize, and we can’t wait to see what comes out of this project.

The HackadayPrize2018 is Sponsored by:



Scotty Allen Visits Strange Parts, Builds an iPhone

พุธ, 03/28/2018 - 00:01

Scotty Allen has a YouTube blog called Strange Parts; maybe you’ve seen his super-popular video about building his own iPhone “from scratch”. It’s a great story, and it’s also a pretext for a slightly deeper dive into the electronics hardware manufacturing, assembly, and repair capital of the world: Shenzhen, China. After his talk at the 2017 Superconference, we got a chance to sit down with Scotty and ask about cellphones and his other travels. Check it out:

The Story of the Phone

Scotty was sitting around with friends, drinking in one of Shenzhen’s night markets, and talking about how bizarre some things seem to outsiders. There are people sitting on street corners, shucking cellphones like you’d shuck oysters, and harvesting the good parts inside. Electronics parts, new and used, don’t come from somewhere far away and there’s no mail-ordering. A ten-minute walk over to the markets will get you everything you need. The desire to explain some small part of this alternate reality to outsiders was what drove Scotty to dig into China’s cellphone ecosystem.

Where does a cell phone come from, anyway? Well, there are four main parts: the case, motherboard, screen, and battery. With those in hand, plus some fiddly assembly, you’re done. Except you’re not. Through the course of our talk, Scotty mentions the need to laser off the anodization from the back of the case, because it’s used as an antenna and needs electrical contact. But where do those four parts come from? A screen isn’t just a screen, but a stack-up of LCD, digitizer, polarizers, and so on. Assembling these properly from their component parts requires tooling, and an even deeper trip down the rabbit hole, which of course meant a trip to see someone in a screen repair shop. All of which are, of course, nearby.

In the end, he’s got an iPhone, just like any other, but it’s his phone. And you can have your own phone too.

Don’t Fear the Phone!

Scotty’s takehome for hackers is to not be intimidated by smartphones. After all, they’re just small computers inside a case, and they’re designed to be put together by normal people on an assembly line. They’re absolutely more fragile but if you take your time with it, there are user-serviceable parts inside. And come to think of it, we’d like to see more smartphone hacks.

So check out Scotty’s Superconference talk, where he also goes into adding an earphone jack to an iPhone and many tips and tricks he discovered along the way. Then let us know what your next smartphone project is going to be.

Everything You Wanted to Know about Transformers (But were Afraid to Ask)

อังคาร, 03/27/2018 - 22:30

[Jim Pytel] has a lot of very good instructional videos on his channel, and he recently added one you’ll enjoy on transformers. You probably know that transformers convert one AC voltage into another AC voltage. Some step up voltage, some step down voltage, and others simply pass voltage through but isolate the input from the output.

The 40 minute video covers basics including how the transformer works, the meaning of the turns ratio, and how transformers reflect impedance. You probably should understand how to compute AC power, but if you need a refresher [Jim] has a video for that, too.

The video focuses mostly on power transformers, but many of the same concepts apply to signal transformers, too. We’ve always thought it is interesting that a transformer is just a generator where the rotating magnetic field is generated electrically instead of through shaft rotation. Or, if you prefer, a generator is just a transformer with a rotating magnet replacing the primary.

[Jim] promises to cover non-ideal transformers in a later video, but for this one, the transformers are ideal. That means the power output is the same as the power input, which would be nice, but isn’t realistic. Real transformers lose some power due to a variety of factors and there’s a lot of science behind coil winding and core material to minimize those losses to the extent practical.

If you want our take on transformers, we did that a while ago. If you think transformers are always magnetic, though, think again.

How To Reverse Engineer Mechanical Designs for 3D Modeling

อังคาร, 03/27/2018 - 21:00

If you’re interested in 3D printing or CNC milling — or really any kind of fabrication — then duplicating or interfacing with an existing part is probably on your to-do list. The ability to print replacement parts when something breaks is often one of the top selling points of 3D printing. Want some proof? Just take a look at what people made for our Repairs You Can Print contest.

Of course, to do that you need to be able to make an accurate 3D model of the replacement part. That’s fairly straightforward if the part has simple geometry made up of a primitive solid or two. But, what about the more complicated parts you’re likely to come across?

In this article, I’m going to teach you how to reverse engineer and model those parts. Years ago, I worked for a medical device company where the business model was to duplicate out-of-patent medical products. That meant that my entire job was reverse engineering complex precision-made devices as accurately as possible. The goal was to reproduce products that were indistinguishable from the original, and because they were used for things like trauma reconstruction, it was critical that I got it right.

We were reverse engineering parts with features that were too small to be seen by the human eye, so we had some fancy equipment like high-magnification optical comparators. But, for the parts most hobbyists want to make, all you’ll need is a set of digital calipers. Very precise models can cost hundreds of dollars, but basic digital calipers can be found for well under $30—and that’s probably all you need.

Two Important Skills

Why are calipers the only measurement tool you need? Well, the human brain is very bad at estimating lengths with any kind of accuracy. “About 5 inches?” is the best most of us are capable of. So, you need a way to get accurate measurements for reference features. Conversely, however, the human brain is very good at two things: making relative judgments, and making inferences.

Relative Judgments:

This is why you can look at an analog clock without numbers, and still guess the time with pretty good accuracy. It’s why you can look at a glass and say “yup, that’s about half full.” In regards to reverse engineering, it’s why you can look at the picture above and deduce that X is probably 2″ and Y is probably 1″.

Inference:

This is the most important skill you need to develop for successful reverse engineering. It’s all about making logical deductions from your measurements, based on the fact that the original part was designed by another human. For instance, if you measured a part like the image above, it might come out to 3.99″ instead of 4.00″. You can probably infer that the person who designed intended it to be 4.00″, and that the 0.01″ difference was probably a result of manufacturing tolerances, or a slight error in measurement.

As humans, we like to use nice even numbers when we design parts. Lengths, diameters, and radii are usually round numbers in the design phase. Angles are usually even divisions of 90 degrees—almost always something like 15°, 45°, or 60°. Of course, the caveats here are measurements that either the designer didn’t explicitly specify (like the hypotenuse length of a triangle), or when the designer has to use a specific measurement to interface with another part or has a similar design constraint (like with an injection molded part, where you need a draft angle of 1 or 2 degrees).

When making inferences, you’ll also need to take into account whether the designer was working with metric units or standard units. If you take a measurement with your calipers and it comes out to 0.197″, you might assume it’s due to manufacturing and guess it to be 0.200″. When, in reality your calipers were actually rounding up 0.19685″, which is exactly 5mm.

The Process:

I use a basic workflow of five steps when reverse engineering a part. As when you’re designing a part from scratch, you should start with a rough shape and add features to make it more detailed.

Step 1: Determine units

Start by asking yourself where the part was made, and more specifically where it was designed. A part originating outside of the United States is probably metric, but what if it was designed by an American company and simply manufactured overseas? Alternatively, what if it was designed overseas, but with the purpose of interfacing with an American product?

Let’s take a look at headphone plugs to illustrate the complexity of this problem. The original standard plug was an American design and the specifications call for a diameter of 1/4″ (6.35mm) on the barrel of the plug. The mini headphone jack, which became popular later and is probably what you have now, is exactly 3.5mm (0.137795″). I can’t find solid information on this, but I assume that’s because it was designed for international standards.

Once you have a hunch about the units being used, try taking some measurements in inches and millimeters on some major features, like the length, width, or diameter of the main body. See which (inches or millimeters) are closer to nice round numbers, while still keeping in mind that manufacturing is never perfect, and they probably won’t be dead on.

Step 2: Important primitives

Start by taking measurements of the main features of the part, and modeling those. It’s best to start with features that would be primitive solids, in order to get an accurate base. You also want your most accurate measurements (which are usually the first ones) to be the “important” features. These are features which affect the functionality of the part, such as where it will mate with another part.

Using the headphone plug as an example again, you can see that the plug barrel is very important to the functionality of the part. It’s what interfaces with the audio output device’s jack, and so it’s critical to get those measurements as accurate as possible. The body of the plug is used for two things: to house the wire connections, and to provide a gripping surface. Neither of those things is especially dependent on accurate dimensions. Therefore, you should start with designing the plug barrel — specifically by beginning with a cylinder based on the overall length of the barrel and its diameter.

Step 3: Unimportant Primitives

Next, it’s a good idea to go ahead and model the rest of the primitives that aren’t as important. The reason you want to do this before getting to the details of the important parts is simply a matter of logistics. It can sometimes be difficult to add major features without a nice “clean” primitive to reference. There are ways around that of course, but it’s usually best to have a complete “rough-in” of your part before you begin with the detail work.

Step 4: Important Details

Now that you’ve got your rough part, it’s time to start adding the important details. This is the most difficult part of the entire process, as those details are hard to measure but are still essential to the functionality of the part.

For this plug, you need to get measurements for each of the two revolved cuts into the primary cylinder that you started with. To do this, you need their diameters (5 and 6), as well as information on their positions (1 and 3) and their widths (the difference between 2 and 1, and the difference between 4 and 3). Why measure from the tip, instead of from the other end? Because the tip is what actually fits into the female jack, so the distance of these features from the tip is more relevant than the distance from the grippy end. You also need to be careful not to stack tolerances — all measurements should be taken from a hard point. That’s because each measurement you take will have a margin of error, and you don’t want those errors to add up.

The tip is next, which presents a problem: how do you measure the angle of the tip? You could use a protractor, but that’s not necessary and could present its own problems. One way would be to measure the distance from the tip to the widest point. But that will give you accuracy issues caused by the rounded tip and the beveled (fillet) edge. There just aren’t any “hard” edges to measure from. Instead, a better way is to make some inferences on the angle and the choices the original designer made. Drawing lines on a photo can be surprisingly helpful, especially if your software has 2D CAD-like measuring capabilities.

Right away, we can see that the angle between the center axis (blue line) and tip slope (green line) looks pretty darn close to 45 degrees. That’s about as round of a number as you can get, and it’s probably safe to assume that was the original design intent. But, did you notice that another problem has come up? The intersection of blue and green lines isn’t at the end of the tip (orange line). This is because instead of having a sharp tip, it was made with a blunt rounded tip. That means that when modeling the tip, you can’t easily use the green/blue intersection as a reference point for the revolved cut.

Instead, you can make the reference the intersection of the green and yellow lines. Now, this is also an imaginary point, as there is no hard edge there. The fillet makes it impossible to get a perfect measurement with calipers. But, it should be a little easier than the tip. Making a 45° revolved cut from there would leave you with a flat tip, which would then be rounded with an edge fillet (the fillet radius matching the radius of the circle of the flat tip).

For the rest of the fillets on the plug, you’re going to have to guess and make inferences. Try some different radii until they match those of the part. Getting this right takes some practice and experience, but it shouldn’t be too hard to get it close. Luckily, the radii of bevels (fillets) and dimensions of cut off edges (chamfers) aren’t integral to the functionality of the plug, because they’re just there for the spring clip to grip. So, it just needs to be close.

Step 5: Unimportant Details

This last step is pretty easy, because it’s not essential that you get it exactly right. On our headphone jack, the “grip” area could be completely different from the original part, and it would still work just fine as long as the wire connectors still fit inside. You can make it look like the original part, or you could take some artistic liberties (like knurling the entire area for better grip).

Now, I’ve obviously simplified the modeling of this particular part. In reality, it’s actually an assembly made up of a few parts to allow internal wire connections, and an electrical connection to the female jack. If you were actually trying to reproduce this jack (a TRS connector specifically), you would have to take it apart and model each part individually. But, hopefully this has given you an idea of the process you would need to use.

What If You Don’t Have Access to the Original Physical Part?

This is a challenge you might tackle if you were trying to reproduce the likeness of a product, or if you’re modeling for purely aesthetic reasons. Maybe you want to 3D print a prop from a movie, or you want to make a reproduction of a rare product you can’t get your hands on. The latter was the case for me when I modeled this Braun SK2 radio. All I had for reference was this photo I found on Google.

So, how do you model an object you don’t have physical access to? Well, most importantly, it wasn’t necessary for it to be exactly right. I wasn’t planning on actually making a physical radio, and even if I was it wouldn’t have needed to interface with any original SK2 parts. All that mattered was that it looked right.

Of course, the goal is always to make it as close as possible. In this case, I started with what I knew: this was a radio designed by Dieter Rams during in his heyday at Braun. At that time especially, Rams was obsessed with simple aesthetics, and so I knew he would have designed this radio with straightforward proportions and only non-frivolous features. Furthermore, Rams is German, so I could safely assume he was using the metric system.

I got a basic sense of scale by looking at the dial and controls in the photo. The dial needs to be readable (probably from arm’s reach), so that gives a minimum size for the radio. The knobs are obviously intended to be manipulated with your fingers, so it’s easy to make some inferences on their size based on that. They couldn’t be too large, so that gives a maximum for the size of the radio.

With a good idea of the general size of the radio in mind, I could come up with the proportions of the body. The height appears to be about 1/2 of the length, or at most 2/3. The depth appears to be between 1/3 and 1/2 of the length. The dial and controls take up 1/2 of the face/speaker grill. Of that half, the dial takes up about 3/4 and the knobs take up 1/4. The holes in the grill are in a square pattern, and so that’s a simple matter of counting how many rows and columns there are. The spaces are close to the same size as the holes, so that tells us the diameter of the holes.

And from there, it was mostly just about making the details look right. It takes a little bit of experimentation to get a good match, but you can always tweak the model as you go. It might not be perfect (you may notice that I got the proportion of the center plastic in the dial wrong), but the idea is make it visually accurate. At the beginning of this article, I mentioned that the human brain is terrible at guessing exact measurements, but good at relative judgments. That’s why it’s best to focus on getting the correct proportions between distinct features.

Working that way should allow you to make convincing reproductions without taking measurements. The more references you can find visually, the more accurate you can make the reproduction. If you were trying to reproduce a movie prop, for example, you could use the entire scene to make relative judgments. You might use the actor’s hands as a reference, or a pen on a table — or really any familiar object that you can use for scale. Take advantage of any other items in the frame to get a better idea of the size of the object you’re trying to model.

Better Beer Through Gene Editing

อังคาร, 03/27/2018 - 18:00

As much as today’s American beer drinker seems to like hoppy IPAs and other pale ales, it’s a shame that hops are so expensive to produce and transport. Did you know that it can take 50 pints of water to grow enough hops to produce one pint of craft beer? While hops aren’t critical to beer brewing, they do add essential oils and aromas that turn otherwise flat-tasting beer into delicious suds.

Using UC Berkley’s own simple and affordable CRISPR-CaS9 gene editing system, researchers [Charles Denby] and [Rachel Li] have edited strains of brewer’s yeast to make it taste like hops. These modified strains both ferment the beer and provide the hoppy flavor notes that beer drinkers crave. The notes come from mint and basil genes, which the researchers spliced in to yeast genes along with the CaS9 protein and promoters that help make the edit successful. It was especially challenging because brewer’s yeast has four sets of chromosomes, so they had to do everything four times. Otherwise, the yeast might reject the donor genes.

So, how does it taste? A group of employees from a nearby brewery participated in a blind taste test and agreed that the genetically modified beer tasted even hoppier than the control beer. That’s something to raise a glass to. Call and cab and drive across the break for a quick video.

Have you always wanted to brew your own beer, but don’t know where to start? If you have a sous vide cooker, you’re in luck.

Main image via [Craft Beer].

Via [Science Daily]

Retrotechtacular: A 180 GB Drive from 1994

อังคาร, 03/27/2018 - 15:00

Hard drive storage has gone through the roof in recent years. Rotating hard drives that can hold 16 terabytes of data are essentially available today, although pricey, and 12 terabyte drives are commonplace. For those who remember when a single terabyte was a lot of storage, the idea that you can now pick up a drive of that size for under $40 is amazing. Bear in mind, we are talking terabytes.

In 1994, that was an unimaginable amount of storage. Just a scant 24 years ago, though, you could get 90 gigabytes — 0.09 terabytes — if you didn’t mind buying an IBM mainframe and a RAMAC disk storage unit. You can see a promotional video digitized by Archive.org, below. Just keep in mind that IBM has a long history of calling disk drives DASD — an acronym for Direct Access Storage Device. You pronounce that “dazz-dee”, as you’ll hear in the video.

IBM still has a product page for the device, which they stopped promoting in 1998 and stopped supporting in 2010. Amazing, actually, that the product had such a short lifespan.  From the product page:

The RAMAC 2 Array Subsystem consists of a Array Controller that is populated with from two to sixteen B13 or B23 drawer arrays. Each B13 drawer has a capacity of 5.67 gigabytes (GB) and each B23 drawer with 3390-3 emulation has a capacity of 11.35 gigabytes (GB), thereby providing a range of capacities from 11.35 GB to 180 GB in a single, compact footprint. The new IBM ULTRASTAR* XP 3.5-inch SCSI disk drives in the RAMAC 2 Array Subsystem double the capacity of the previous RAMAC drawer, thereby providing outstanding improvement in the storage capability in a single rack.
The array controller can be configured as either a dual cluster controller or a quad cluster (2 cluster pairs) controller thereby providing options for performance tailoring and/or intermix of DASD volume emulation modes. Options for controller cache sizes range from 64 megabytes (MB) to 2 GB. Cache memory is also resident in the drawer.

Each drawer was stuffed with 2 GB SCSI disks. Granted, it was arranged as RAID 5, and we are sure the I/O bandwidth to the controller was high. Still, it is amusing that they hoped to impress you by telling you that you could now fit 180 GB of storage in only 15.8 square feet! The power requirements were significant, too.

For all of that, articles from the time indicate performance wasn’t that great, and there was a limit on at least some of the controllers of 180 GB, even as larger drives became available. Since many IBM installations were leased and hardware sold at various prices, it is hard to peg down exactly what one of these beasts cost. But it is a good bet that a stripped down version was no less than $20,000 — which would be a lot more adjusted for inflation.

If you’ve got a thing for old IBM hardware, you might enjoy some of the posts we’ve covered about the IBM 1401 at The Computer History Museum. Or, if you want something closer to the RAMAC’s time period, you can always play games on an AS/400.

https://archive.org/download/IBM_RAMAC_Array_Family_1994_Tape/IBM_RAMAC_Array_Family_1994_Tape.mp4

 

IQ Makes Smarter Motors

อังคาร, 03/27/2018 - 12:00

We think of motors typically as pretty dumb devices. Depending on the kind, you send them some current or some pulses, and they turn. No problem. Even an RC servo, which has some smarts on board, doesn’t have a lot of capability. However, there is a new generation of smart motors out that combine the mechanical motor mechanism with a built-in controller. [Bunnie] looks at one that isn’t even called a motor. It is the IQ position module.

Despite the name, these devices are just a brushless DC motor (BLDC) with a controller and an API. There’s no gearing, so backdriving the motor is permissible and it can even double as a motion sensor. The video below shows [Bunnie] making one module track the other using just a little bit of code.

To show an even more impressive example, [Bunnie] put together a 2-axis robot arm using these modules and some cardboard (see the second video, below). Not only was it built in about an hour, but it is programmed by an operator moving it as desired.

The nice thing about the smart motor concept is you can tell it a position and speed and it handles all the drive considerations. This can get complex with a regular motor. This isn’t the only smart motor out there, of course. And BLDCs are common enough — you can even build your own if you like.

https://bunniefoo.com/bunnie/iq_motion_copy_demo_lbr.mp4 https://bunniefoo.com/bunnie/iq_2axis_robot.mp4

Solve 2D Math Equations Colorfully

อังคาร, 03/27/2018 - 09:00

Electronics can be seen as really just an application of physics, and you could in turn argue that physics is the application of math to the real world. Unfortunately, the way most of us were taught math was far from intuitive. Luckily, the Internet is full of amazing texts and videos that can help you get a better understanding for the “why” behind complex math topics. Case in point? [3Blue1Brown] has a video showing how to solve 2D equations using colors. If you watch enough, you’ll realize that the colors are just a clever way to represent vectors and, in fact, the method would apply to complex numbers.

Honestly, we don’t think you’d ever solve equations like this by hand — at least not with the colors. But the intuitive feel this video can give you for how things work is very valuable. In addition, if you were trying to implement an algorithm in software this would be tailor-made for it, although you wouldn’t really use colors there either we suppose.

The video is a bit long, but it is packed full of interesting insights. He shows several ways to represent functions in addition to the color method. Just watching the animations can bring on some “aha” moments. If you are a programmer at heart, you’ll no doubt pick up on the binary search aspect of the algorithm, too.

If you want a refresher on complex numbers, we did that already. If you are into software-defined radio, don’t forget all this would apply to I and Q signals, too.

The Obscure Electronics Tools You Didn’t Know You Needed

อังคาร, 03/27/2018 - 06:00

The right tool for the job can turn a total headache into a 30-second operation. This is all the more important when you’re trying to streamline an assembly process, and the reason why you’ll find so many strange and wonderful purpose-built tools on any production line. With a nod to that old adage, [EvilMadScientist] have collected the tools you didn’t know you needed – until now.

If you’re wiring big through-hole boards all day, you’ve probably bemoaned the uneven bends on all your resistors. How did the big companies get it right way back when? They used a tool to set the distance of the resistor legs just right. What about DIP ICs? It’s a total pain trying to take them fresh out of the tube and get them to seat in a socket, but there’s a tool to do that too. It’s actually a two-part series, and while we’re sure you’ve all seen a solder sucker before, the fresh take on helping hands is pretty ingenious.

Overall, it’s a combination of little things that, with a bit of cash or a day’s work, you can have in your own lab and once you’ve got them, you won’t ever want to go back. Be sure to tell us about your favourite obscure tools in the comments.

Now that you’ve got your tools to hand, why not wrap them all up in a handy workstation?

A Bar Graph for Beer Fridge Vitals

อังคาร, 03/27/2018 - 03:00

[ChrisN219] has an antique Coke machine that used to hold glass bottles. Now it holds around 30 tall boy cans of his favorite post-work suds. The only problem is that [Chris] has no idea how many cans are in it without opening up the door or keeping tally on a nearby slate board. Enter the Arduino.

He wanted to make something completely non-invasive to the machine (phew!) while using as many parts he already had as possible. The result is a simple circuit that uses an ultrasonic sensor mounted inside the machine to ping the depths, and a Nano in a nifty 3D printed box up top to do some math and display the number of cans remaining as a simple bar graph. The sensor reads one bay, and the code multiplies by two to get the total. It was touch and go there for a minute as he wasn’t sure that the HC-SR04s would get a good response from the cylindrical cans. Not only did they give a good reading, the first test was quite accurate.

[Chris] recently finished Mk. II, which replaces the momentary (and the Coke logo) with a second HC-SR04. The first version required the push of a button to do inventory, but now he simply walks up to the machine and knows at a glance if it’s time to make a beer run.

Okay, so maybe you don’t have cool old Coke machine problems. But surely you can find something that needs pinging, like an inconvenient rain barrel.

It’s a Nixie! It’s a VFD! No, It’s a Custom LED Display in a Tube

อังคาร, 03/27/2018 - 01:00

Like the look of Nixies but they just seem a little overdone? Or perhaps you just don’t want the hassles of a high-voltage power supply? Then maybe these faux-Nixie LED “tube” displays will find a way into your next clock build.

For his 2018 Hackaday Prize entry, [bobricius] decided that what the world needs is a Nixie that’s not a Nixie. To that end, each display is formed by seven surface-mount LEDs soldered to a seven-segment shaped PCB and slipped into a glass tube. The LEDs are in 4014 packages so they’re only 4 millimeters long, but what they lack in size they make up for in brightness. We’re not sure if it’s a trick of the camera, but the LEDs certainly seem to put off a bluish glow that’s reminiscent of vacuum-fluorescent displays — it’s like a Nixie and a VFD all rolled up in one package.  The current case, which hides the clock circuitry on the lower part of the PCB, is just plastic, but this would look spiffy in a fine wooden case.

Could this be another Nixie tube killer that never was? Perhaps, but wherever it ends up, we like the look of it, and we’re glad it’s one of the early Hackaday Prize entries. Have you got something to enter in the greatest hardware competition on Earth? If not, get cracking!

The HackadayPrize2018 is Sponsored by:



Cutting Edge of 3D Printing Revealed At Last Weekend’s Midwest RepRap Festival

อังคาร, 03/27/2018 - 00:01

The last three days marked the 2018 Midwest RepRap Festival. Every year, the stars of the 3D printing world make it out to Goshen, Indiana for the greatest gathering of 3D printers and printing enthusiasts the world has ever seen. This isn’t like any other 3D printing convention — everyone here needs to take the time to get to Goshen, and that means only the people who want to be here make it out.

Over the weekend we covered some amazing hacks and printer builds from MRRF. The ‘BeagleBone On A Chip’ has become a complete solution for a 3D printer controller. This is a great development that takes advantage of the very under-used Programmable Real-Time Units found in the BeagleBone, and will make an excellent controller for that custom printer you’ve been wanting to build. E3D has announced they’re working on an automatic tool-changing printer. It’s a slight derivative of their now-defunct BigBox printer, but is quite possibly the best answer to multi-material filament printers we’ve ever seen. There’s some interest from the community, and if everything goes well, this printer may become a kit, or something of the sort. Filament splicing robots also made an appearance at this year’s MRRF, and the results are extremely impressive. Now you can create multi-color prints with the printer you already own. Is it expensive? Yes, but it looks so good.

This wasn’t all that could be found at MRRF. There were hundreds of printers at the event, and at last count, over 1300 attendees. That’s amazing for a 3D printer convention that is held every year in the middle of nowhere, Indiana. What were the coolest sights and sounds coming out of MRRF this year? Check out the best-of list below.

Glitter Printers

MRRF had a 30-foot-tall delta printer. MRRF had the latest products and projects from the best 3D printing companies out there. There was an R2D2. The star of the show, though, was the glitter printer.

[Scott Ziv] got his hands on a Z Corp Z402 printer through some means or another. This is an ancient 3D printer from the early 2000s prints using a powder by usingan inkjet-like device to dispense a binding agent to hold it together. [Scott] didn’t want to buy the powder and binder, so he simply mounted a laser diode to the carriage and tried to melt some powder. Sugar didn’t quite work, but he did have success in an unlikely place: glitter. Yes, glitter. The stuff that kills dolphins.

[Scott] found a guy selling a few buckets of glitter for about a dollar a pound. This glitter is mostly PLA PET, surprisingly, with a little bit of aluminum and some polyester in there as well. It melted well with the diode laser, although the parts produced crumble to bits if they’re moved at all. [Scott] encased his best prints in epoxy resin, and while it’s not something that can create functional prints, it is a printer that prints in glitter.

The writeup for this build will eventually be documented on [Scott]’s website.

Pellet Extruders

If you’re building a big printer, you’re going to need a lot of plastic. Standard 1kg spools are great if your printer fits on a desk, but for those massive build volume printers, filament just becomes too expensive. The better way is pellets, the raw material of the plastic world. Do this, though, and you need a way to extrude and melt those pellets.

[haqnmaq] has created a pellet extruder for large-format printers, capable of printing very large objects with very cheap plastic. The key component of anything that extrudes pellets is the auger; commercial, industrial injection molders use very clever and very expensive augers, but [haq] is using a standard, off-the-shelf 1/2″ wood auger for this build. This drill bit is driven by a NEMA 23 motor with a 47:1 gearbox, and the heat comes from two 300W heater bands.

This project is on Hackaday.io, you can check that out here. [haqnmaq] is extruding plastic with it, now the only thing left to do is to mount it to a printer.

Prusa’s Latest Triumph

A while ago, Prusa introduced the multi-extrusion upgrade to the Prusa i3. It works, but there is a downside — each filament you want to multi-extrude requires a separate stepper motor. If you want four colors of filament, that’s four motors.

There’s a better way of doing things. It was announced a few weeks ago, but at MRRF we got our first look at the new multimaterial upgrade.  Instead of a stepper for each different filament, this is a weird little machine that takes five filaments, selects one, and pushes it into the extruder motor on the x-carriage.

Here’s what’s going on with this new extruder. The ‘filament selector box’ — or whatever we’re calling it — consists of five holes in the back that accept different filaments, and a single hole on the front that accepts PTFE tubing that feeds right into the main extruder on the x-carriage. In between the front and the back, the filament feeds through a series of rollers that selectively feed filament to the front. When the printer wants to change filament, the movable carriage on the front moves from one output to the other. Filament is automatically sliced inside the machine. Think of it as a printer-mounted version of the filament-slicing robots we saw this weekend, only very much cheaper and significantly more clever.

The entire contraption is driven by a small board with three motor drivers. This is the Prusaino, and will make a great CNC controller when it’s sold by itself.

This is a fantastic advancement in the state of multimaterial printing. It’s not shipping yet, but we can’t wait to get our hands on this thing.

Infinite Build Volume Printers and Hurdy Gurdies

Last year, the best thing at MRRF, and possibly the greatest 3D printing innovation of the year, was the infinite build volume printer. What makes this an infinite build volume printer? It can print a beam that’s about six inches wide, six inches tall, and millions of miles long. You supply the plastic, power, and time. It’s absurdly clever, another company quickly released their plans for one, and [Brook] of Printrbot connected with [Bill Steele], the guy at MRRF with the prototype, to create a slightly more professional-looking version.

This year, that prototype made it out to MRRF. It works, and it was printing off tiny little models of airplanes.

There are a few things going on with this printer that aren’t readily apparent. Only the first few inches of that kapton bed are heated. This makes sense; the printer really only prints on the first few millimeters of the bed, anyway. By not heating the end of the bed, the prints pop right off. There are a few issues with the bed wandering off to one side, but future versions will have a 1mm crown on the rollers, keeping the bed centered. [Bill] is using a Raspberry Pi to queue up his models and have everything slide off the printer. He took this machine to Oshkosh a while ago, and printed 1,500 of those little planes in a weekend. It’s a great machine and we can’t wait to see this thing make it into production.

Want something strange and weird? Here’s a hurdy gurdy:

What’s a hurdy gurdy? String bagpipes. That’s what it sounds like, at least. This hurdy gurdy has a pair of strings that are played with keys (giving you a specific note), and two drone strings that… drone. Turn a crank, which turns a wheel, which vibrates strings. Yeah, it’s slightly weird and sounds like string bagpipes.

This hurdy gurdy was a kit made of wood, and the wheel for these is usually made out of maple. Here, the wheel is constructed out of red PLA for the structure, and a thin band of carbon fibre filament on the rim. It works well enough, although how it sounds is greatly dependent on the listener.

High Metal Content Filament

Metal filament, or PLA that has a bit of tiny metal particles embedded inside, has been around for a while. If your prints are very good, you can smooth them to a high shine. The metal content of these filaments hover around 60-70%. It’s good, it’s heavy, but here’s some filament with a metal content of 80%. Yes, there is a difference, and this filament is worth the price.

This filament comes from The Virtual Foundry, and pictures will never do it justice. This feels like real metal. It is as if these objects were cast in bronze and plated with copper or stainless steel. The specs for the 316L Stainless filament give it a density of 4.05, a metal content of 81%, and it prints well at 210C. This is the greatest metal filament I’ve ever seen, and if you throw an object printed in this into a kiln, it comes out as a solid metal object.

How much does it cost? $100 for a kilogram of the copper filament. Keep in mind it’s significantly heavier than regular ‘ol PLA.

Can’t Wait Till Next Year

MRRF is simply the greatest 3D printing convention on the planet. Everyone who is there wants to be there. Everyone has awesome stuff to show off. This is where the future of 3D printing is on display, and it’s all happening in Goshen, Indiana, a town whose WalMart has a hitch for horse and buggies. No, we can’t explain it, but we’re going again next year.