Maker builds a DIY SLA 3D printer for less than $30

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This SLA 3D printer can be created using materials found throughout your home — and an Arduino.

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Although many 3D printers strive for simplicity and affordability, this one surely takes the cake. Whereas a device under $500 may catch your attention, one that costs less than a Saturday night dinner surely will hold it. Buildyourownsla.com user “Mystamo” recently created a DIY SLA 3D printer for less than $30 that prints from the top-down or bottom-up, all powered through an Arduino Uno (ATmega328).

SLA typically features a bottom-up style due to issues like the need for more resin and layer height control. A projector or laser diode sits underneath the resin tank with transparent bottom and a non-stick surface, pointing upwards to cure the resin.

For his build, Mystamo had taken his top-down device and wanted to test as to whether it would work with his ACER 5360 720P projector for a bottom-up design as well. After some investigation, the projector was indeed suitable for the job without requiring much further customization other than removing its focus screw for manipulating the focus wheel and a little fine-tuning of the focus.

The Maker reveals that since he didn’t have Z-axis limits, he set the build plate just slightly above the resin surface with some resin pointing out of the his perf board holes. Mystamo acquired an inexpensive stepper drive that was soldered directly to the pin, and added a few connectors for easy removal. It also runs at 1/16 micro stepping. Beyond that, he refined his 3D printer by employing the Arduino to run a very simple HTL code with only minor modifications.

From there, the 3D printing process was ready to begin with 8-second exposures on the first three layers, and 2.5 second exposures on all other layers, all at 0.05mm per layer. While this particular design doesn’t use any 3D-printed parts itself, it still embodies true DIY spirit as the entire thing was devised using items found around the house. And in case you’re wondering, yes it works, as seen with his latest print: a Terminator skull.

Intrigued? Learn more by heading over to the Maker’s forum post here.

Plant Friends is an AVR based plant environmental monitor system

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These bamboo characters will become friends with your plants. 

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Have you ever wanted to know the exact moment that your precious plants get thirsty? A Maker by the name of Dickson Chow has created an environmental monitor system called Plant Friends that will tell you just that.

The environment monitoring solution is comprised of two sub-systems: wireless sensor nodes in the form of cute, laser-cut bamboo characters and a base station. The adorable bunny, robot and dinosaur nodes monitor soil moisture, air temperature and humidity of your indoor plants, and will alert you via email or SMS when they are in need of a drink. Aside from these notifications, Chow envisions his Plant Friends having the ability to:

• Monitor multiple plants.
• Run on batteries.
• Be low power, maybe having to swap each battery every 4-6 months.
• Include an Android app.
• Come with little to no maintenance.
• Have an enclosure to organize and protect the electronics.

To accomplish this, Chow embedded each bamboo character with an open-soure Moteino dev board (ATmega328P) along with sensors (moisture, humidity and temperature), an indicator LED light and a battery meter. The Maker says he elected to use Moteino instead of the Arduino Uno as the clone comes with an optional radio transceiver, which enables the Plant Friends to transmit and receive data wirelessly.

Each character is assigned to an individual plant. Information such as temperature, humidity and soil moisture is collected by the sensor, and sent over to the base station via its transceiver. The hub houses another Moteino that acts as a gateway to receive the RF signals, a USB Wi-Fi adapter, and a Raspberry Pi where the data is stored in a MySQL database. The information is then analyzed and displayed on an accompanying Android app. This allows any plant-grower to look at real-time and historical data right on their phone.

Prone to dying plants? With spring officially here, you may want to check out Plant Friends.

Nellie is a 3D-printed weed-picking robot

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This Arduino-powered bot may one day help farmers stay weed-free. 

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Other than shoveling several inches of snow, there’s one outdoor chore that anyone would surely welcome robotic assistance: weeding. While there are already a number of plowing bots out in existence today, thanks to one Maker, the daunting lawn care task may soon be taken care of as well.

A recent entry in MAKE: Magazine and Cornell University’s Pitch Your Prototype competition, Maker Mike Rigsby has developed a 3D-printed robot capable of, you guessed it, pulling out weeds! While at first this may sound like yet another mechanism to increase laziness, weeds are actually a serious problem for farmers all around the world — and it’s only getting worse. Take for instance Pigweed, which grows up to three inches per day and has become resistant to the dominant weed killers, threatening the nation’s soybean and corn crops.

“This is a serious attempt to address an agricultural problem,” Rigsby told the magazine. “I suspected that robots could handle the weeds and that the time to start working on such a solution is now, before the weeds develop further resistance to chemicals.”

And so Nellie was born. The robot spots and plucks them the old-fashioned way, one at a time. The current proof-of-concept is powered by a trio of Arduino Unos (ATmega328), a pair of Arduino motor shields, a Pixy camera, a Ping ultrasonic sensor, eleven AA NiMh batteries, a servo motor, a four-wheel drive base, along with some custom 3D-printed parts that were constructed using two AVR powered MakerBot Replicator 2.

How it works is relatively simple. The Pixy camera spots a weed, then feeds the data over to the Arduino processors which relay the commands to the motor controller module to activate the grabber and close the pincer. Meanwhile, the Arduino-controlled motor shield enables the robot to move about the land in the right direction. At the moment, the device is only designed to roll over carpet.

Should the Maker win the contest’s grand prize, however, Rigsby hopes to use the winnings to devise another working prototype with a little more oomph, which can navigate a farm’s terrain. And who knows, perhaps in the coming months, everyday gardeners will be able to take advantage of Nellie, too.

“To advance the project requires money for parts. Nellie’s daughters and sons will need a heavy duty chassis that will run between rows of plants, reaching to the side to eliminate offensive weeds. They need multiple cameras and better vision to pinpoint the target. Weeds will be eliminated by pulling, burning, cutting, digging, electrocuting or some combination of methods,” Rigsby adds.

Until then, you can watch it in action below. Now this would make for a great Hackay Prize entry as well. Just sayin’.

Video: Maker creates some Arduino-powered sound-sensing art

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Art Vader?

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They say art is in the eye of the beholder, and well, this wall-mounted piece is stunning. Making matters even better, it’s Star Wars themed!

Crafted by Christopher Connell, the ambient Darth Vader poster wirelessly reacts to music playing in a room with various LED color-changing effects. Comprised of chrome and black paint, flooring underlayment and some other traditional art supplies, the 4’ x 5’ piece is embedded with an Arduino Uno (ATmega328), a sound impact sensor, three MOSFETs, three 220k Ohm resistors, an LED strip, a pair of mini breadboards and a 12V battery pack.

“Regular drawing and painting just didn’t seem to fit the bill of a creative outlet for me, so I decided to design my own mix of art, Arduino, LEDs, sound sensors and Star Wars, all sprinkled with a little computer code,” Connell writes.

Want to devise one of your own? Head over to the project’s log here. Meanwhile, you’ll want to see it in action below.

Building a sub-$100 President Obama detector for your desk

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Introducing the Internet of Presidential Things.

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While the rise of smart devices and a surge of security-related issues around constant connectivity have garnered quite a bit of buzz as of late, journalist and amateur electronics enthusiast Andrew McGill recently decided to show off a more fun and simplistic side of the burgeoning Internet of Things (IoT).

Given his new role at Washington, DC-based National Journal, McGill elected to demonstrate just how easy it is to make a new “Internet thing” using an Arduino Uno (ATmega328), an Arduino Ethernet shield, a bunch of white LEDs and an upcycled plastic box. With materials in hand, he set out to build something politics-related: A President Obama detector.

It’s exactly what it sounds like… a desktop device that will tell you where the American leader is located. Okay, so it doesn’t tell you exactly where President Obama is, as that would probably be a pretty big security threat and would take a bit longer than an hour and $100 in supplies to create. However, by mining the President’s public schedule, the aptly-dubbed Barack Obama Detector alerts the user if he is in Washington DC, elsewhere in the U.S. or overseas using one of three light bulbs.

Interested in learning more about the project? Check out McGill’s entire writeup in the National Journal here. We couldn’t help but wonder if this would prove to be rather useful in in the workplace. Imagine having a minimalistic gadget that could notify you of your boss’ whereabouts: in the office, out of the building, or in a meeting.

This instrument creates music based on the emotional status of Twitter users

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“We’re pickin’ up good (social) vibe-rations.”

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Initially designed as a Master’s degree project at the University of Limerick in Ireland by Cian McLysaght, Social Vibes is a unique installation that creates music based the emotional expressions of Twitter users.

The harmonic tunes are derived from a continuous stream of input by multiple Twitter users as well as the explicit interaction from those tweeting the steampunk-esque machine via its @vibe_experiment handle. Data associated with the emotional status of those online is mined from the social network via its open-source API. Meanwhile, Vibe adopts fundamental sound mechanisms used in a vibraphone (hence its name) and is powered by an Arduino Uno (ATmega328).

How it works is simple. When a user sends a post to Vibe directly, they are given instant remote control over the instrument. At that moment, their emotional state is shown on the device’s built-in LCD display as their tweet/musical composition is ambiently shared. A user can tweet using their Twitter account or by Twitcam, where the Vibe streams live video and audio online of the instrument being played.

“For example if a user tweets ‘The sun is out, I’m happy,’ the code I’ve written will strip out key words and strings associated with the user’s emotional state, within the tweets, i.e. ‘I’m happy,’ and translate this to a musical notation. Mining Twitter’s API, allows a continuous stream of data. These emotional states are then mapped to specific notes on the physical musical instrument, located in a public space. The tempo of the musical expression will be entirely based upon the speed and volume of the incoming tweets on the Twitter API,” McLysaght writes.

The instrument itself is comprised of a dozen musical tones of varying pitches, which are created by striking any one of 12 keys using the ATmega328-driven solenoids. What’s fun is that this enables users to hijack the instrument in a playful manner, as well as provides those with musical knowledge the opportunity to compose simple musical arrangements. When users are not tweeting the instrument directly, the Vibe will revert to mining the Twitter API.

Interested? Head over to its official page to learn more, or watch it in action below!

Automate your Etch-A-Sketch to recreate famous artwork

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Watch this Etch-A-Sketch reproduce the Mona Lisa.

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Dating back to the 1960s, Etch-A-Sketches have been one of the most iconic toys in pop culture history, having remained relatively unchanged for decades. The toy is comprised of a thick, flat gray screen housed inside a red plastic frame with two white knobs in its the lower corners. Twisting the dials move a stylus that displaces aluminum powder on the back of the screen, leaving a solid line. And, it doesn’t matter who you are or how artistically-enabled you might be, drawing any lineographic image on an Etch-A-Sketch is pretty darn hard.

In an effort to ease the creation of an aluminum particle masterpiece, like the Mona Lisa, Maker Evan Long decided to automate the process using an Arduino Uno (ATmega328). The Maker modded the original white knobs with 3D-printed custom mounts, which would house the two stepper motors and ULN2803 to switch the 12V required for the steppers. These makeshift knobs were bound to the plastic frame using rubber tubing and Gorilla Glue. Meanwhile, the Arduino was tasked with controlling the pair of motors as it etched the picture.

Once the hardware setup was complete, Long installed the SketchTheEtch.app on the Arduino using a simple Python script to take in .PNG files and produce vector art. Though the maximum resolution is about 550 x 370, the Maker recommends images no larger than 500 x 320 to account for any error. Tracing starts from the top of the image and works its way from left-to-right, as seen in the video below.

“The Arduino Firmware works by receiving a vector to draw. It draws the vector and then sends a message back to the host indicating it is ready for the next command. The ImagePoints.pyscript takes a black and white image as input and traces through the solid black pixels. All the black pixels must form a single contiguous region.”

Interested in modding your Etch A Sketch to recreate some of history’s most famous pieces of art? If so, head over to the Maker’s official project page here. In the meantime, you can see it in action below!

This hidden door illuminates with the touch of your hand

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This Lord of the Rings-inspired hidden door won’t take you to middle-earth, but a basement movie theater instead! 

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In J.R.R. Tolkein’s “Lord of the Rings,” the Doors of Durin (also known as West-gate of Moria) were built in the dark cliffs of Silvertine Mountain and protected the great Dwarvencity of Khazad-dûm. They were made like a flush door, the jambs invisible to the eye, and matched so perfectly with the mountain rock that, when closed, the entryway could not be seen. Adhering to the same principle, a Maker by the name of “Neular” has devised a Gates of Durin-inspired hidden entrance of his own, powered by an Arduino Uno (ATmega328).

While the panel may initially appear to be just any other part of the wall, a simple swipe of his hand reveals a more elaborate, illuminated replica of Doors of Durin to the mines of Moria. And it’s not just a decorative trick, either. The panel actually serves as a hidden entrance into the homeowner’s basement movie theater.

To bring this magical idea to life, the Maker built a shadow box out of some 2x4s and plywood he had lying around, while adding a plexiglass front covering over the door. Inside, he affixed several strips of ultra-bright LED lights, which he had secured using liquid nails. The actual “Lord of the Rings” design was cut from the vinyl and then painted over.

“Right now, the door opens automatically after a touch of the hand. Soon, I will integrate voice recognition, so you will first have to touch it to illuminate it, then speak the elvish word for friend ‘Mellon’ in order to gain access,” he writes. “I’m also going to cause the light just above this door to flicker and go out right before the door illuminates to have a much larger BAAM! effect.”

The door is controlled using an Arduino Uno (ATmega328), which the Maker programmed to sense capacitive touch. Meanwhile, the soon-to-be-added voice recognition will be completed using an EasyVR Shield 2.0.

You’ll have to see it in action to really get its full effect. Watch below! Interested in learning more? Head over to the project’s step-by-step log here.

This DIY moisture monitor will help keep your houseplants alive

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With spring just around the corner, it’s never too early to start thinking about planting.

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Writing for Popular Mechanics, Alexandra Chang explained why she recently created an open-source, Arduino-powered DIY moisture monitor to ensure that her plants received the optimal living conditions.

“My perennials always died because I watered them too little or too much, or put them somewhere too dark or too hot,” she says. 

“[So] I vowed to keep my plants alive [and] turned to Arduino. I’d been looking for an excuse to try out this microcontroller platform, which I knew could be programmed to do a lot of cool things. Why not use it to save my ailing amaryllis?”

According to Chang, the project took a single afternoon and resulted in a smart sensor that was capable of reading and displaying soil-moisture levels, light intensity and temperature. 

For the build, the Maker turned to no other than an Arduino Uno Starter Kit (ATmega328) which included the following parts:

• Solderless breadboard ($5)
• Assorted wires ($7)
• Thermistor ($2)
• Photoresistor ($1)
• 10K-ohm resistors ($8 per pack)
• Potentiometer ($1)
• LCD display ($10)

After finding instructions for a number of Arduino-based plant sensors online, such as the GardenBot, the ArduGarden and Soil IQ’s solar-powered sensor, Chang converged certain elements from each to devise something that suited her own skill level and needs.

The DIY gardening device features two soil probes responsible for measuring how much the soil resists the flow of electricity — or how moist it is. By adding a photoresistor (light sensor) and a thermistor (temperature sensor), then connecting them to a programmed Arduino, she was left with a gadget that could monitor the environment of a single plant. Meanwhile, an LCD display was used to show its moisture, temperature, and light readings in variable resistance values.

Interested in learning more? Head over to the project’s official writeup in Popular Mechanics here.

This old-school telegraph sounder can tap out tweets

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This project connects 19th century technology with today’s cellular networks.

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Long distance telegraphy first appeared back in 1792 in the form of semaphore lines, which sent messages to a distant observer through line-of-sight signals. Commercial electrical telegraphs were later introduced in 1837. These devices were physically connected by wires between stations, and operators tapped out messages in Morse code on a small, paddle-like device called a key.

Fast forward 178 years and one Maker is breathing new life into the old-fashioned mechanism. Devon Elliot recently outfitted an old telegraph sounder seated in a wooden resonator with some modern-day electronics so that it could tap out tweets.

“This project was an attempt to connect technology rooted in the 19th- and early 20th-centuries with 21st-century networks,” Elliot writes. “The results bridge those time periods through the technologies used. The telegraph sounder was used as the starting point and is the output of the device.”

To start, the Maker connected an Arduino Uno (ATmega328) to the machine, which was tasked with controlling the sounder by triggering the coils — turning them on and off via one of the board’s digital I/O ports. Elliot used the Arduinomorse library to translate messages into Morse code and activate the sounder. Meanwhile, a handful of other components including a resistor, diode, and transistor were added to protect the digital pin of the Arduino by separating the activation signals from the powering of the coils.

The other main component is a FONA board. This device from Adafruit is an all-in-one cellular phone module that enables Makers to add voice, text, SMS and data to projects in an adorable little package. In this case, Elliot connected the FONA to the Arduino, and programmed the ATmega328 based board to check for SMS messages periodically. If an inbox message was found, it would then translate it into Morse code and tap them out on the sounder.

Rounding out the design, the Maker mounted the electronics onto a piece of black acrylic and attached it to telegraph. “This was convenient as nothing had to be permanently altered to the historic device. Wires were attached to it via the provided screw terminals, so those can be detached and the base unscrewed to remove the electronics,” he adds.

Upon completion, Elliot was left with a standalone telegraph sounder that was not only connected to cellular phone networks, but equipped to receive SMS messages and tap them out in Morse code. The modded device can operate off batteries if necessary, allowing it to work anywhere with cell reception. The machine’s cellphone number is paired with a Twitter account, which was also set up to send an SMS to that number whenever the account is mentioned. If you’d like to activate the telegraph with a Twitter message, go ahead and tweet @ldntelegraphco.

Interested? Head over to the project’s official page here. If you enjoyed this retrofitted device, you may also want to check out this 1930s typewriter social networking machine.