Christmas Star Uses Two AA Batteries

December 16, 2015 by Al Williams 5 Comments

When [hkdcsf] was a teenager, he made a Christmas star with an up counter driving decoder logic and using transistors to light LEDs in festive patterns. He’s revisited this project using modern techniques including a microcontroller, a DC/DC converter, and constant current LED drivers.

The project uses two AA batteries, and that’s what makes the DC/DC converter necessary. Blue LEDs have a forward voltage of just over 3V, and the LED driver chip requires about 0.6V of overhead. Two fresh AAs will run a tad above 3V, but as they discharge, or if he’s using rechargeables, there just won’t be enough potential. To make sure the star works even with whatever LEDs are chosen, the converter takes the nominal 3V from the batteries and converts it to 3.71V.

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Halloween Doorbell Prop In Rube-Goldberg Overdrive

November 14, 2015 by Elliot Williams 8 Comments

[Conor] wired up his 3D-printed coffin doorbell to an array of RGB LEDs, a screaming speaker, and a spinning skull on a cordless screw driver to make a “quick” Halloween scare. Along the way, he included half of the Adafruit module catalog, a relay circuit board, and ESP8266 WiFi module, a Banana Pi, and more Arduinos of varying shapes and sizes than you could shake a stick at.

Our head spins, not unlike [Conor]’s screaming skull, just reading through this Rube Goldbergy arrangement. (We’re sure that’s half the fun for the builder!) Smoke ’em if ya got ’em!

Start with the RGB LEDs; rather than control them directly, [Conor] connected them to a WiFi-enabled strip controller. Great, now he can control the strip over the airwaves. But the control protocol was closed, so he spent a week learning Wireshark to sniff the network data, and then wrote a Bash script to send the relevant UDP packets to turn on the lights. But that was not fancy-schmancy enough, so [Conor] re-wrote the script in Go.

Yes, that’s right — a Go routine on a Banana Pi sends out custom UDP packets over WiFi to a WiFi-to-LED-driver bridge. To make lights blink. Wait until you see the skull.

The plastic skull has Neopixels in each ping-pong ball eye, controlled by an Arduino Nano and battery taped to the skull’s head. The skull is cemented to a driver bit that’s chucked in a cordless drill. A relay board and another Arduino make it trigger for 10 seconds at a time when the doorbell rings. Finally (wait for it!) an Arduino connected to the doorbell gives the signal, and sets a wire high that all the other Arduini and the Banana Pi are connected to.

Gentle Hackaday reader, now is not the time for “I could do that with a 555 and some chewing gum.” Now is the time to revel in the sheer hackery of it all. Because Halloween’s over, and we’re sure that [Conor] has unplugged all of the breadboards and Arduini and put them to use in his next project. And now he knows a thing or two about sniffing UDP packets.

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Dalek-Berry-Pi Mower

November 2, 2015 by Anool Mahidharia 8 Comments

There’s something about lawn mowers and hackers. A desire to make them into smart, independent robots. Probably in preparation for the day when Skynet becomes self-aware or the Borg collective comes along to assimilate them into the hive. [Ostafichuk] wanted his to be ready when that happens, so he’s building a Raspberry-Pi powered, Dalek costumed Lawn Mower that is still a work in progress since starting on it in 2014. According to him, “commercial robot lawn mowers are too expensive and not nearly terrifying enough to be any fun, so I guess I will just have to build something myself…”

His first report describes the basic skeletal structure he built using scrap pieces of wood. Two large lawn tractor wheels and a third pivot wheel help with locomotion. The two large wheels are driven by geared motors originally meant for car seat height adjustments. A deep cycle 12V battery, and solar panels for charging would take care of power. A raspberry-pi provides the brain power for the Dalek-Mower and L298N based drivers help drive the motors. The body was built from some more planks of scrap wood that he had lying around. While waiting around for several parts to arrive – ultrasonic sensors, accelerometer, 5V power supply modules – he started to paint and decorate the wood work. Generous amounts of water repellent paint and duct tape were used to make it weather proof. His initial plan was to use python for the code, but he later switched to programming in c along with wiringPi library. Code for the project is available from his bitbucket git repository. Load testing revealed that the L298N drivers were not suitable for the high current drawn by the motors, so he changed over to relays to drive them.

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Take A Ride On My Magic Carpet

November 1, 2015 by James Hobson 12 Comments

For an awesome Halloween edition of [PrankvsPrank], they decided to make a remote controlled “magic carpet” for [Aladdin]. It’s absolutely fantastic.

[PrankvsPrank] isn’t really known for making stuff we’d feature on Hackaday, so they got some help with the project from the [CaseyNeistat] a New York YouTuber. As you can probably guess, at the heart of this magic carpet is actually an electric skateboard. A Boosted Board to be specific– it was a very successful Kickstarter a few years ago.

They built a lightweight frame out of plastic pipe and wrapped fabric around it to make it look like a proper carpet out of the cartoon. Once they had it all set, they took it for a spin through the streets of NYC, catching people’s reactions along the way.

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PIR Jack-o-Lantern Sees Them Coming

October 31, 2015 by Kristina Panos 4 Comments

Planning to make that carved a pumpkin last past Halloween night? Forget the tealight or LED candle—here’s an easy, no-solder project that will make it extra special. By default, this jack-o-lantern looks like it has a flickering flame, but get close enough to it and it goes crazy with color.

All you need is an LED matrix, a Rainbowduino to drive it, a PIR motion sensor to trigger the random colors, and a power source. [Alpha Charlie] kept the electronics from becoming pumpkin-flavored with some plastic bags. Since he used the PIR as the jack-o-lantern’s nose, there is a bit of plastic behind it to keep moisture from interfering.

[Alpha Charlie]’s build instructions are quite detailed, which makes this project even simpler if you’ve never used a PIR before. There are lots of ways you could build on this project to make it your own, like using trick-or-treater motion to trigger screams or spooky sounds, or add more sensors to make it more interactive. Watch it react after the break.

If you have nothing else at all to do between now and trick-or-treat time, you could bust out the soldering iron and recreate this 70-LED matrix jack-o-lantern. Blinkenlights too safe for your tastes? Fire-breather it is, then.

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Zombie Slap Results In Glorious Selfie

October 31, 2015 by James Hobson No comments

[Donnie Plumly] likes to spice things up at the office around holidays. This Halloween he decided to make an office photo booth — with a bit of a twist. He calls it the Zombie Selfie.

He cast his arm in silicone to make a gruesome zombie hand, which he set up with a vibration sensor. If you touch the arm (he encourages you to slap it), an Arduino picks up the vibration which initiates the picture taking sequence!

He’s using an IR LED with the Arduino to trigger the camera, and then an Eye-Fi card in it automatically transfers it to a computer in a DropBox. An IFTTT script then publishes it to Twitter for all to see under the account @ZombieSelfie! There are some pretty amusing ones already!

And so you can preview your Zombie Selfie, he also threw a monitor up — there’s no going back after the picture is taken though! It’ll be posted straight to Twitter.

When it comes to custom photo booths though, its hard to top this robotic artist who will actually paint your picture for you!

Hacklet 82 – Halloween Hacks 2015

October 31, 2015 by Adam Fabio 5 Comments

Halloween is when the ghouls start haunting and the hackers start hacking. All hallows eve is the perfect holiday for eerie blinking LEDs, spooky audio oscillators, and wild animatronics. We had a double dose of Halloween hacks last year on the Hacklet. This year we’re bringing you even more of the best Halloween hacks on hackaday.io!

We start with [dougal] and Halloween Blinky Eyes. [Dougal] wanted to create the effect of creatures peeking at you from the dark corners of the room, and he’s certainly nailed it. A strip of WS2812 LEDs is the trick here. Pairs of LEDs light up, blink, and fade away like spooky eyes. The Strip is controlled by a Particle Core using Adafruit’s NeoPixel Library, though [Dougal] plans to move to the FastLed library. Everything is powered by a USB power pack. This hack isn’t much to look at with the lights on, so check out the video to see these eyes really shine!

Next up is [controlmypad] with Blair the Witch Project. A normal trip to Home Depot turned paranormal when [controlmypad] spotted an awesome witch decoration. The free-standing mannequin had some basic animatronics and the all important manual trigger. [controlmypad] already had a discarded electric wheelchair. After replacing the chair batteries he modified it with a Sabertooth 2×32 Motor Controller and a standard radio control receiver. A spare channel was connected to Blair’s manual trigger. An aluminum tube joins the witch and the scooter. The hardest part of this hack was keeping Blair’s skirt out of the scooter wheels. Home Depot to the rescue! A simple hoop made of lawn edging plastic keeps the fabric and wheels apart.

[Alex Cordonnier] and his team participated in Boilermake 2015, a 24 hour Hackathon at Purdue University. The fruit of their labor is Trick or Tweet, the tweeting Jack-o’-lantern. Yes folks, we now have the internet of gourds. Hiding inside Trick or Tweet is a Raspberry Pi and a Pi Camera. The pumpkin itself is also a giant capacitive touch switch. Touching the pumpkin triggers a count down after which Trick or Tweet snaps a photo. It then adds some spooky Halloween overlays, a pun or two, and throws the whole thing up on twitter @PumpkinPiPics. [Alex] hasn’t uploaded the code yet, but we’re guessing it consists of a few Python scripts. Pretty awesome for 24 hours of work!

Sometimes Halloween hacks take on a life of their own. That’s exactly what happened when [Hari Wiguna] sat down with a few parts he ordered from China. Happy Halloween 2015 is the result. [Hari’s] order included some potentiometers, a two color OLED display, and some Arduino clones. In no time [Hari] had three pots wired up to the Arduino’s analog inputs. The OLED quickly followed, displaying graphics via the Arduino’s I2C bus. He really wanted a Jack-o’-lantern though. It took a bit more tweaking, but eventually [Hari] was successful. The first pot sets eye size. The second controls eye rotation. The third pot changes the width of Jack’s mouth. [Hari] has all the code for this hack up on his most recent project log.

Not spooked enough? If you want to see more Halloween projects, check out our newly updated Halloween hacks list! Did I miss your project? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet; As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!