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There’s an interesting side effect of creating a popular piece of science fiction: if you wait long enough, say 30 or 40 years, there’s a good chance that somebody will manage to knock that pesky “fiction” bit off the end. That’s how we got flip phones that looked like the communicators from Star Trek, and rockets that come in for a landing on a tail of flame. Admittedly it’s a trick that doesn’t always work, but we’re not in the business of betting against sufficiently obsessed nerds either.

Coming in right on schedule 32 years after the release of Metroid on the Nintendo Entertainment System, we now have a functional laser arm cannon as used by the game’s protagonist Samus Aran, courtesy of [Hyper_Ion]. It’s not quite as capable as its video game counterpart, but if your particular corner of the solar system is under assault from black balloons you should be in good shape. Incidentally no word yet on a DIY Power Suit that folds the wearer up into a tiny ball, but no rush on that one.

Modeled after the version of the weapon Samus carried in 2002’s iconic Metroid Prime, [Hyper_Ion] 3D printed the cannon in a number of pieces that screw together in order to achieve the impressive final dimensions. He printed it at 0.3 mm layers to speed up the process, but as you can probably imagine, printing life-size designs like this is not for the faint of heart or short of time. While the use of printed threads does make the design a bit more complex, the fact that the cannon isn’t glued together and can be broken down for maintenance or storage is a huge advantage.

Ever popular NeoPixel strips give the cannon a bit of flash, and a speaker driven by a 2N2222 transistor on an Arduino Nano’s digital pin allows for some rudimentary sound effects with nothing more than a PWM signal. In the video after the break you can see how the lights and sounds serve as a warning system for the laser itself, as the cannon can be seen “charging up” for a few seconds before emitting a beam.

Of course, this is the part of the project that might have some readers recoiling in horror. To provide some real-world punch, [Hyper_Ion] has equipped his arm cannon with a 2.5W 450nm laser module intended for desktop engraving machines. To say this thing is dangerous is probably an understatement, so we wouldn’t blame you if you decided to leave the laser module off your own version. But it certainly looks cool, and as long as you’ve got some proper eye protection there’s (probably) more dangerous things you can do in the privacy of your own home.

Shame this kind of technology wasn’t really practical back when [Ryan Fitzpatrick] made this fantastic Power Suit helmet for a Metroid fan production.

We’d seen it done with buttons, switches, gestures, capacitive touch, and IR remote, but never like this. [electron_plumber] made an LED that can be blown out like a candle, and amazingly it requires no added sensors. The project uses an Arduino to demonstrate turning a tiny LED on and off in response to being blown on, and the only components are the LED and a resistor.

[electron_plumber] used an 0402 LED and thin wires to maximize the temperature responses.
How is this done? [electron_plumber] uses an interesting property of diodes (which are the “D” in LED) to use the LED itself as a temperature sensor. A diode’s voltage drop depends on two things: the current that is being driven through the diode, and the temperature. If the current is held constant, then the forward voltage drop changes reliably in response to temperature. Turning the LED on warms it up and blowing on it cools it off, causing measurable changes in the voltage drop across the device. The change isn’t much — only a handful of millivolts — but the effect is consistent and can be measured. This is a principle [Elliot Williams] recently covered in depth: using diodes as temperature sensors.

It’s a clever demo with a two important details to make it work. The first is the LED itself; [electron_plumber] uses a tiny 0402 LED that is mounted on two wires in order to maximize the temperature change caused by blowing on it. The second is the method for detecting changes of only a few millivolts more reliably. By oversampling the Arduino’s ADC, an effectively higher resolution is obtained without adding any hardware or altering the voltage reference. Instead of reading the ADC once, the code reads the ADC 256 times and sums the readings. By working with the larger number, cumulative changes that would not register reliably on a single read can be captured and acted upon. More details are available from [electron_plumber]’s GitHub repository for LEDs as Sensors.

Embedded below is a video that is as wonderful as it is brief. It demonstrates the project in action, takes a “show, don’t tell” approach, and is no longer than it needs to be.

In the past we have seen LEDs that can be blown out like candles in different ways; one used a microphone to detect blowing while another used a thermistor to detect the temperature change from blowing. [electron_plumber]’s project is notable not only for using no added parts, but also for being documented in a way that just about anyone can get up and running, and that’s something we always like to see.

Light painting: there’s something that never gets old about waving lights around in a long exposure photo. Whilst most light paintings are single shots, some artists painstakingly create frame-by-frame animations. This is pretty hard to do when moving a light around by hand: it’s mostly guesswork, as it’s difficult to see the results of your efforts until after the photo has been taken. But what if you could make the patterns really precise? What if you could model them in 3D?

[Josh Sheldon] has done just that, by creating a process which allows animations formed in Blender to be traced out in 3D as light paintings. An animation is created in Blender then each frame is automatically exported and traced out by an RGB LED on a 3D gantry. This project is the culmination of a lot of software, electronic and mechanical work, all coming together under tight tolerances, and [Josh]’s skill really shines.

The first step was to export the animations out of Blender. Thanks to its open source nature, Python Blender add-ons were written to create light paths and convert them into an efficient sequence that could be executed by the hardware. To accommodate smooth sliding camera movements during the animation, a motion controller add-on was also written.

The gantry which carried the main LED was hand-made. We’d have been tempted to buy a 3D printer and hack it for this purpose, but [Josh] did a fantastic job on the mechanical build, gaining a solidly constructed gantry with a large range. The driver electronics were also slickly executed, with custom rack-mount units created to integrate with the DragonFrame controller used for the animation.

The video ends on a call to action: due to moving out, [Josh] was unable to continue the project but has done much of the necessary legwork. We’d love to see this project continued, and it has been documented for anyone who wishes to do so. If you want to check out more of [Josh]’s work, we’ve previously written about that time he made an automatic hole puncher for music box spools.

Thanks for the tip, [Nick].

As if you already weren’t agonizing over whether or not you should build your own arcade cabinet, add this one to the list of compelling reasons why you should dedicate an unreasonable amount of physical space to playing games you’ve probably already got emulated on your phone. [Rodrigo] writes in to show off his project to add some flair to the lighted buttons on his arcade controller. (Google Translate)

The wiring for this project is about as easy as you’d expect: the buttons connect to the digital inputs on the Arduino, and the LEDs on the digital outputs. When the Arduino code sees the button getting pressed, it brings the corresponding LED pin high and starts a fade out timer using the SoftPWM library by [Brett Hagman].

It’s worth noting that the actual USB interface is being done with a stand-alone controller, so the Arduino here is being used purely to drive the lighting effects. The more critical reader might argue that you could do both with a single microcontroller, but [Rodrigo] was in a classic “Use what you’ve got” situation, and already had a USB controller on hand.

Of course, fancy lit arcade buttons won’t do you much good without something to put them in. Luckily we’ve covered some fantastic looking arcade cabinets to get you inspired.

Tired of risking his life every time he had to signal a turn using his hands while riding his bicycle in rainy Vancouver, [Simon Wong] decided he needed something a bit higher tech. But rather than buy something off the shelf, he decided to make it into his first serious Arduino project. Given the final results and the laundry list of features, we’d say he really knocked this one out of the park. If this is him getting started, we’re very keen to see where he goes from here.

So what makes these turn signals so special? Well for one, he wanted to make it so nobody would try to steal his setup. He wanted the main signal to be easily removable so he could take it inside, and the controls to be so well-integrated into the bike that they wouldn’t be obvious. In the end he managed to stuff a battery pack, Arduino Nano, and an HC-05 module inside the handlebars; with just a switch protruding from the very end to hint that everything wasn’t stock.

On the other side, a ATMEGA328P microcontroller along with another HC-05 drives two 8×8 LED matrices with MAX7219 controllers. Everything is powered by a 18650 lithium-ion battery with a 134N3P module to bring it up to 5 VDC. To make the device easily removable, as well as keep the elements out, all the hardware is enclosed in a commercial waterproof case. As a final touch, [Simon] added a Qi wireless charging receiver to the mix so he could just pull the signal off and drop it on a charging pad without needing to open it up.

It’s been some time since we’ve seen a bike turn signal build, so it’s nice to see one done with a bit more modern hardware. But the real question: will he be donning a lighted helmet for added safety?

 

[JohnathonT] has a two-year-old who can’t reliably tell time just yet. Every morning, he gets up before the rooster crows and barges into his parents’ room, ready to face the day.

In an effort to catch a few more Zs, [JohnathonT] built a simple but sanity-saving clock that tells time in a visual, kid-friendly way. Sure, this is a simple build. But if a toddler is part of your reality, who has time to make one from logic gates? The hardware is what you’d expect to see: Arduino Nano, a DS1307 RTC, plus the LEDs and resistors. We think an RGB LED would be a nice way to mix up the standard stoplight hues a bit.

At a glance, little Mr. Rise and Shine can see if it’s time to spread cheer, or if he has to stay in his room and play a bit longer. At 6:00AM, the light powers on and glows red. At 6:50, it turns yellow for 10 minutes. At the first reasonable hour of the day, 7:00AM, it finally turns green. In reading the code, we noticed that it also goes red at 8:00PM for 45 minutes, which tells us it also functions as a go-to-sleep indicator.

When his son is a little older, maybe [JohnathonT] could build him  a clock that associates colors with activities.

There are plenty of cheap projection clocks available, but as [Thomas Pototschnig] points out in this project, where’s the fun in just buying something? He set out to build a cheap projection clock using a small LCD screen, a cheap LED backlight, and a cheap lens. Cheap is the order of the day here, and [Thomas] succeeded admirably, creating a design that can be made with a couple of cheap PCBs, a 3D printer and the other parts mentioned above. He does a nice job of laying out his thinking in this design, showing how he calculated the projection path and made other decisions. His project has room to grow as well: it runs from an Arduino compatible STM32 that could handle many things other than showing the time if you were inclined to expand the project further.

[Thomas] has released all of the files he created for the project, including a number of options for the case that can use C-mount and Sony E-mount lenses. I’m not sure if you would want to attach your expensive camera lenses to a home-made projector like this, but it’s good to have the option if you have a dead E-mount lens that you were going to tear apart for parts anyway.

We’ve covered plenty of persistence of vision (POV) displays before, but this one from [Vadim] is rather fun: it’s built on top of a PC fan. He’s participating in a robot building competition soon and wanted to have a POV display. So, why not kill two birds with one stone and build the display onto a fan that could also be used for ventilation?

The display is a stand-alone module that includes a battery, Neopixels, Arduino and an NRF240L01 radio that receives the images to be displayed. That might seem like overkill, but putting the whole thing on a platform that rotates does get around the common issue of powering and sending signals to a rotating display: there is no need for slip connections.

[Vadim] goes into a good level of detail on how he built the display, including the problems he had diagnosing a faulty LED chip, and why it is important to test at each stage as it is easier to debug when the display isn’t whizzing around at high speed.

It’s a bit of a rough build that uses more protoboard than might be necessary, but we’re keeping our fingers crossed that it doesn’t fly off during the competition.

Light painting is a technique which allows you to “draw” on a photograph by moving a light past the camera during a long exposure shot. While it can be difficult to master, light painting allows for some incredible effects such as text and images that appear to be hovering in mid-air. Think of it like a very slow but much cooler version of an augmented reality app.

[Reven] recently wrote in to tell us about the Arduino light painter he put together, and while DIY (and even commercial) light painting gear isn’t exactly new at this point, we think he’s raised the bar a bit with his design. With the addition of a slick 3D printed enclosure and on-board display and menu system, his light painter looks exceptionally professional for being built out of hardware he had on hand.

On his blog, [Reven] has done a phenomenal job of documenting the build from start to finish. Not only does he include a detailed Bill of Materials and the STL files so you can build your own version of his light painter, he walks the reader though his design process and explains why he did the things he did. Even if you aren’t interested in building a light painter, there’s almost certainly something of interest for anyone who’s ever looked at a pile of parts on their workbench and wondered how they were going to turn it into a functioning device.

Powered by an Arduino Uno, the light painter provides a user interface on a 16×2 LCD which allows control over not only the brightness of the WS2812 LED strips but selecting and loading different images from the micro SD card. The case was designed in FreeCAD, and while [Reven] mentions there are a number of issues which could be improved, satisfies all his design goals.

We covered the original Adafruit project that [Reven] based his code all the way back in 2013, though there’s certainly been more modern interpretations of the idea since then.

Quality software development examples can be hard to come by. Sure, it’s easy to pop over to Google and find a <code> block with all the right keywords, but having everything correctly explained can be hit or miss. And the more niche the subject, the thinner the forum posts get. Bucking the downward trend [HansLuijten] provides an astoundingly thorough set of LED strip patterns in his comprehensive post titled Arduino LED strip effects.

Don’t let the unassuming title lead you astray from the content, because what’s on offer goes beyond your average beginner tutorial on how to setup a strand of NeoPixels. [HansLuijten] is thorough to a fault; providing examples for everything from simple single color fades and classic Cylon eyes to effects that look like meteors falling from the sky. Seriously! Check out the video after the break. Those chasing lights you see around theater signs? Check. Color twinkle and sparkle? Check. Color wipes and rainbow fades? Check, and check.

At this point, an average forum post would be a jumbled mess of source which only works on an authentic Arduino Duemilanove running at 3.3v sitting on top of the 2nd printing of the author’s favorite issue of Make. But not here! These samples work with Adafruit’s easy to use NeoPixel library as well as FastLED, the quickest pixel in the West. On top of that the examples are clear and concise and explanation is plentiful. But the best part is definitely that each effect has a video clearly showing what it looks like.

If only everything were this easy to use, the open source revolution would already be here.



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