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If your idea of a six-course meal is a small order of chicken nuggets, you might have missed the rise of sous vide among cooks. The idea is you seal food in a plastic pouch and then cook it in a water bath that is held at a precise temperature. That temperature is much lower than you usually use, so the cook times are long, but the result is food that is evenly cooked and does not lose much moisture during the cooking process. Of course, controlling a temperature is a perfect job for a microcontroller and [Kasperkors] has made his own setup using an Arduino for control. The post is in Danish, but Google translate is frighteningly good.

The attractive setup uses an Arduino Mega, a display, a waterproof temperature probe, and some odds and ends. The translation does fall down a little on the parts list, but if you substitute “ground” for “earth” and “soil” you should be safe. For the true epicurean, form is as important as function, and [Kasperkors’] acrylic box with LEDs within is certainly eye-catching. You can see a video of the device, below.

The switches, LEDs, and relays are all pretty standard fare. The real heart of the project is the temperature control. Many controllers use a PID (proportional/integral/derivative) to hold the temperature, but this project takes a more pragmatic approach. Depending on how far from the set point the temperature is, the controller simply drives the heating element differently and measures more or less frequently to adjust. For example, if the temperature is more than two degrees low, the heating element is left on constantly. As it gets closer, though, the heating element runs for 10 seconds, there’s a 5 second wait, and then the algorithm reads the temperature again.

There’s a lot of debate about how precise the temperature has to be. Apparently, for things like fish, a wide range of temperatures isn’t a problem. Eggs, however, need tighter control because their proteins can denature (whatever that means).

There’s also a safety relay that shuts the whole affair down if the temperature goes very high or low so a bad temperature sensor won’t boil everything away. We might have considered doing that with a bimetallic coil so that even an Arduino failure would not stop it from working.

We’ve seen other attractive sous vide setups. Not to mention the more utilitarian builds made with a crock pot. No matter what it looks like, these projects are probably not going to help your waistline.


Filed under: Arduino Hacks

If your idea of a six-course meal is a small order of chicken nuggets, you might have missed the rise of sous vide among cooks. The idea is you seal food in a plastic pouch and then cook it in a water bath that is held at a precise temperature. That temperature is much lower than you usually use, so the cook times are long, but the result is food that is evenly cooked and does not lose much moisture during the cooking process. Of course, controlling a temperature is a perfect job for a microcontroller and [Kasperkors] has made his own setup using an Arduino for control. The post is in Danish, but Google translate is frighteningly good.

The attractive setup uses an Arduino Mega, a display, a waterproof temperature probe, and some odds and ends. The translation does fall down a little on the parts list, but if you substitute “ground” for “earth” and “soil” you should be safe. For the true epicurean, form is as important as function, and [Kasperkors’] acrylic box with LEDs within is certainly eye-catching. You can see a video of the device, below.

The switches, LEDs, and relays are all pretty standard fare. The real heart of the project is the temperature control. Many controllers use a PID (proportional/integral/derivative) to hold the temperature, but this project takes a more pragmatic approach. Depending on how far from the set point the temperature is, the controller simply drives the heating element differently and measures more or less frequently to adjust. For example, if the temperature is more than two degrees low, the heating element is left on constantly. As it gets closer, though, the heating element runs for 10 seconds, there’s a 5 second wait, and then the algorithm reads the temperature again.

There’s a lot of debate about how precise the temperature has to be. Apparently, for things like fish, a wide range of temperatures isn’t a problem. Eggs, however, need tighter control because their proteins can denature (whatever that means).

There’s also a safety relay that shuts the whole affair down if the temperature goes very high or low so a bad temperature sensor won’t boil everything away. We might have considered doing that with a bimetallic coil so that even an Arduino failure would not stop it from working.

We’ve seen other attractive sous vide setups. Not to mention the more utilitarian builds made with a crock pot. No matter what it looks like, these projects are probably not going to help your waistline.


Filed under: Arduino Hacks

It makes sense considering evolution, but nature comes up with lots of different ways to do things. Consider moving. Land animals walk on four feet or two, some jump, and some use peristalsis or otherwise slither. Oddly, though, mother nature never developed the wheel (although the mother-of-pearl moth’s caterpillar will form its entire body into a hoop and roll away from attackers). Human-developed robots which, on the other hand, most often use wheels. Even a tank track has wheels within. [Joesinstructables] latest robot still uses wheels, but it emulates the slithering motion of a snake, He calls it the Lake Erie Mamba.

The most interesting thing about the robot is that it can reconfigure and move in several different modalities. Like the caterpillar, it can even form a wheel like an ouroboros and roll. You can see that at the end of the video, below.

The base configuration slithers and uses 12 segments, each containing a servo motor. [Joe] uses a key fob remote to drive the snake, although it can move by itself, too. The brains are — what else — an Arduino. In some configurations, the snake carries its own brain and power. In others, there’s a scary-looking wiring harness necessary when the snake becomes a wheel because it has no room in that configuration for the extra items.

Real snakes have different ways they move, and so does the Lake Erie Mamba. In the slithering configuration, passive wheels convert a sine or cosine wave motion into linear motion. [Joe] explains the math behind the motion. If you take off the passive wheels, the snake can move like an inch worm. Turning is complicated in this mode since it can only go forward or backward without some changes. The segments can reconfigure to put a drive wheel in play to introduce the desired lateral motion.

Real snakes can combine the two kinds of motion to “sidewind” and the Mamba can do that too. This does require reconfiguration of the segments and driving some segments with a sine wave and others with a cosine wave.

This isn’t the first time we’ve seen the ouroboros trick. If you think robotic snakes couldn’t possibly be useful, think again. Of course the modular robot that captured our hears is Dtto, which claimed the Grand Prize in last year’s Hackaday Prize.


Filed under: Arduino Hacks, robots hacks

If you’ve ever been curious if there’s a way to program microcontrollers without actually writing software, you might be interested in FlowCode. It isn’t a free product, but there is a free demo available. [Web learning] did a demo of programming a Nucleo board using the system. You can check it out below.

The product looks slick and it supports a dizzying number of processors ranging from AVR (yes, it will do Arduino), PIC, and ARM targets. However, the pricing can add up if you actually want to target all of those processors as you wind up paying for the CPU as well as components. For example, the non-commercial starter pack costs about $75 and supports a few popular processors and components like LEDs, PWM, rotary encoders, and so on.

Price aside, we have serious concerns about building applications with GUIs. It sounds seductive and for simple projects, it is easy and intuitive. However, complex problems get messy quickly when you have flowcharts. This is the same reason complex logic designs moved away from schematics — another form of graphical representation — and went to Verilog and VHDL.

Still, looking at how this is done might give you some ideas and it might be just the ticket for the right application. It isn’t the only graphical game in town, of course. There’s ArduBlock, for example. Another one we’ve looked at is MiniBloq. You can even use Scratch on the Arduino or Raspberry Pi.


Filed under: Arduino Hacks, ARM, Software Development

Following the time-honored YouTube tradition of ordering cheap stuff online and playing with it while the camera runs, [Monta Elkins] bought a Stirling engine that drives a DC motor used as a generator. How much electrical juice can this thing provide, running on just denatured alcohol? (Will it blend?)

The answer is probably not really a spoiler: it generates enough to run “Blink.ino” on a stock Arduino, at least when powered directly through the 5 V rail. [Monta] recorded an open-circuit voltage of around 5 V, and a short-circuit current of around 100 mA at a measured few hundred millivolts. While he didn’t log enough of the points in-between to make a real power curve, we’re guessing the generator might be a better match for 3.3 V electronics. The real question is whether or not it can handle the peaky demands of an ESP8266. Serious questions, indeed!

The video is a tad long, but it’s more than made up for by the sight of an open flame vibro-botting itself across his desk while [Monta] is trying to cool the cold side down with a melting ice cube. Which got us thinking, naturally. If you just had two of the Stirling engines


Filed under: Arduino Hacks, misc hacks

Pi Time is a psychedelic clock made out of fabric and Neopixels, controlled by an Arduino UNO. The clock started out as a quilted Pi symbol. [Chris and Jessica] wanted to make something more around the Pi and added some RGB lights. At the same time, they wanted to make something useful, that’s when they decided to make a clock using Neopixels.

Neopixels, or WS2812Bs, are addressable RGB LEDs , which can be controlled individually by a microcontroller, in this case, an Arduino. The fabric was quilted with a spiral of numbers (3.1415926535…) and the actual reading of the time is not how you are used to. To read the clock you have to recall the visible color spectrum or the rainbow colors, from red to violet. The rainbow starts at the beginning of the symbol Pi in the center, so the hours will be either red, yellow, or orange, depending on how many digits are needed to tell the time. For example, when it is 5:09, the 5 is red, and the 9 is yellow. When it’s 5:10, the 5 is orange, the first minute (1) is teal, and the second (0) is violet. The pi symbol flashes every other second.

There are simpler and more complicated ways to perform the simple task of figuring out what time it is…

We are not sure if the digits are lighted up according to their first appearance in the Pi sequence or are just random as the video only shows the trippy LEDs, but the effect is pretty nice:

 


Filed under: Arduino Hacks, led hacks

If you go to the University of South Florida, you can take the “Makecourse.” The 15-week program promises to teach CAD software, 3D printing, Arduino-based control systems, and C++. Don’t go to the University of South Florida? No worries. Professor [Rudy Schlaf] and [Eric Tridas] have made the entire course available online. You can see several videos below, but there are many more. The student project videos are great, too, like [Catlin Ryan’s] phase of the moon project (see below) or [Dustin Germain’s] rover (seen above).

In addition to a lesson plan and projects, there’s a complete set of videos (you can see a few below). If you are a regular Hackaday reader, you probably won’t care much about the basic Arduino stuff and the basic electronics–although a good review never hurts anyone. However, the more advanced topics about interrupts, SDCards, pin change interrupts might be just the thing. If you ever wanted to learn Autodesk Inventor, there are videos for that, too.

If you don’t need any of the instruction offered, this would still make a great program to offer at a local hacker space or anywhere else where you want to teach build to build. You can see from the variety of student projects that it is well-balanced and lets students focus on areas where they are most interested.

So much educational material is online now that it is hard to find time to see even a fraction of it. We love EdX, for example, but who has the time to take even a fraction of the classes offered? We always love seeing student projects–they give us ideas. [Bruce Land’s] classes, in particular, are always inspirational.


Filed under: 3d Printer hacks, Arduino Hacks

We’ve all enjoyed looking up at a clear night sky and marveled at the majesty of the stars. Some of us have even pointed telescopes at particular celestial objects to get a closer view. Anyone who’s ever looked at anything beyond Jupiter knows the hassle involved.  It is most unfortunate that the planet we reside on happens to rotate about a fixed axis, which makes it somewhat difficult to keep a celestial object in the view of your scope.

It doesn’t take much to strap a few steppers and some silicon brains to a scope to counter the rotation of earth, and such systems have been available for decades. They are unfortunately quite expensive. So [Dessislav Gouzgounov] took matters into his own hands and developed the rDuinoScope – an open source telescope control system.

Based on the Arduino Due, the systems stores a database of 250 stellar objects. Combined with an RTC and GPS, the rDunioScope can locate and lock on to your favorite nebula and track it, allowing you to view it in peace. Be sure to grab the code and let us know when you have your own rDuinoScope set up!

 


Filed under: Arduino Hacks

[Dan], admirably rose to the occasion when his son wanted a new toy. Being a dedicated father — and instead of buying something new — he took the opportunity to abscond to his workbench to convert a Wiimote Nunchuck into a fully wireless controller for his son’s old r/c car — itself, gutted and rebuilt some years earlier.

Unpacking the nunchuck and corralling the I2C wires was simply done. From there, he combined a bit of code, an Arduino pro mini, and two 1K Ohm resistors to make use of an Aurel RTX-MID transceiver that had been lying around. Waste not, want not.

A TI Stellaris Launchpad is the smarts of the car itself, in concordance with a TB6612FNG motor controller. The two Solarbotics GM9 motors with some 3D printed gears give the car some much needed gusto.

In Dan’s own humble words: “nothing out of the ordinary, just a nice example of what one can do with parts mostly gathering dust around any hacker’s house.” If any new parents out there have a spare Wiimote stashed away, you can use the infrared LEDs to make a fairly effective baby monitor.


Filed under: Arduino Hacks, toy hacks

Reader [Jasper] writes in with glowing praise for the TFT_eSPI library for the ESP8266 and the various cheap 480×320 TFT displays (ILI9341, ILI9163, ST7735, S6D02A1, etc.) that support SPI mode. It’s a drop-in replacement for the Adafruit GFX and driver libraries, so you don’t need to rework your code to take advantage of it. If you’re looking to drive an LCD screen with an ESP8266 and Arduino, check this out for sure.

As a testbed, [Jasper] ported his Tick Tock Timer project over to the new library. He got a sevenfold increase in draw speed, going from 500 ms to 76 ms. That’s the difference between a refresh that’s visibly slow, and one that looks like it happens instantly. Sweet.

Improving software infrastructure isn’t one of the sexiest or most visible hacks, but it can touch the lives of many hackers. How many projects have we featured with an ESP8266 and a screen? Thanks, [Bodmer] for the good work, and [Jasper] for bringing it to our attention.


Filed under: Arduino Hacks, Microcontrollers


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