Planet Arduino

The large, bubbling cauldron is a classic mainstay in our Halloween decorations as it evokes imagery of devious witches and their mysterious concoctions. Fed up with this being a mere display piece, element14 Presents’ Katie Dumont created her own interactive enchanted cauldron that allows visitors to brew their own digital potions from an array of distinct ingredients using a whimsical “wand” and NFC-tagged bottles.

To test her idea of mixing ingredients, Dumont began by connecting an Adafruit NFC reader to an Arduino UNO Rev3 along with a strip of RGB LEDs. The code she wrote checks which NFC tag is present every second, and depending on the color, will either add another color or increase/decrease the overall brightness. After the special wand tag has been detected, each pixel along the strip is mixed into a shared, uniform color across all of them.

Upon the heels of this successful experiment, Dumont included another layer of interactivity in the form of a small game where players are presented with a certain color and must try to use the potion bottles to replicate it as close as possible with only red, green, and blue inputs. After selecting a sequence of three colors, tapping the wand will display the result and either flash red or white to indicate failure or success, respectively.

To see more about how Dumont created her enchanted cauldron, you can read the build log here and watch her demo video below!

The post Brew virtual potions by mixing ingredients in this interactive cauldron appeared first on Arduino Blog.

We’re only a few short weeks away from Halloween and that means we’re starting to see the creative projects that makers come up with to celebrate the holiday. Movement, lights, and sound effects are the name of the game when it comes to Halloween decor and the Treat Trough of Terror is the perfect example.

Gord Payne’s Treat Trough of Terror is a fun and unique way to doll out candy to the kids on Halloween while practicing social distancing. Payne can stand on his front stoop and when a trick-or-treater comes along, he can drop candy down the chute to their eager little hands. To turn that into a fun experience, the chute passes through a decorative jack o’ lantern. As the candy slides down the chute, the whole thing lights up and places spooky sound effects.

The chute itself is just PVC pipe cut in half lengthwise and resting on a patio chair. The lights are WS2812B LEDs driven by an Arduino Nano board. The Arduino also controls the sound effects played by a small MP3 player module, with audio output going to a pair of powered speakers. An ultrasonic sensor detects the candy as it slides past on the chute, which tells the Arduino to activate the light and sound effects.

If you want to hand out candy while maintaining at least six feet of distance, this is the perfect project to work on over the next few weeks.

The post The Treat Trough of Terror spits out Halloween candy appeared first on Arduino Blog.

YouTuber Brankly is going to be giving out candy in style this Halloween. Or, more accurately, his automated pumpkin system is going to take care of the task for him.

His large fake jack-o’-lantern sits atop a hilariously smaller skeleton body, and hides inside a servo-driven turntable dispensing mechanism. As it rotates, treats are pushed out of a tongue-like slide mechanism, where it’s detected by two infrared sensors. This detection stops (and reverses) the dispensing plate, while the bowl in front illuminates.

Sounds and lighting are recycled from the modified bowl and pumpkin assembly, and LEDs under control of an Arduino Nano are added to a large button box that starts the cycle. Another Nano runs the rest of the setup, along with a stepper driver board and voltage regulator on a custom PCB.

More build specifics can be found on GitHub.

The idea of a mechanized walking suit to carry you around seems like a great idea, but having a practical leg assembly for it is still a futuristic concept. As seen here however, if you’re still a kid, you might be able to get your dad to carry you around in a custom suit fashioned after a MechWarrior vehicle.

The suit is beautifully designed by creator Gridlock Cosplay, and features an Arduino-powered control system. This allows the little pilot to command the mech’s human “engine” via a joystick and system of lights. The suit also features exterior and interior lights, a pilot cooling fan, spinning “radar” assembly, retractable pilot cage, and of course a cell phone holder in the padded engine compartment.

While Halloween has come and gone, it’s not too early to start brainstorming for next year’s jack-o’-lantern hack. Perhaps you’re thinking about lighting a pumpkin with an Uno-powered array of LEDs, or activating a shield to play scary recorded noises. If, however, you’d like inspiration for something more involved, the New Scientist team’s Arduino-controlled nine-pumpkin rig shows off lots of creative ideas.

The system holds candy in a hacked cereal dispenser, which is released through a long clear plastic tube. But instead of giving away treats for free, it’s activated by an interactive memory game involving four pumpkins on the sides of the assembly.

Trick-or-treaters must tap each pumpkin’s aluminum foil switches in sequence. If replicated in the correct order, they are rewarded with candy. If not, visitors are “treated” to a spray of silly string!

You can read more about New Scientist‘s project in this article, and see it in action below!

Halloween is just around the corner, and the spooky themed tips are just starting to roll in. If you’re looking to one-up the basic store-bought decorations, and maybe teach your kid the basics of an Arduino while you’re at it — why not build a Peek-A-Boo Ghost!

Using an Arduino, two servo motors and an ultrasonic distance sensor it’s pretty easy to make this cute little ghost that covers its eyes when no one is around. They’re using cardboard for the ghost, but if you have access to a laser cutter at your hackerspace, you could make it a lot more robust using MDF or plywood.

When the ultrasonic distance sensor senses someone coming towards it, it’ll trigger the arms to move — though it’d be easy to add a small speaker element too and get some spooky music going as well!

For even more spooky hacks, check out our coverage of last year’s Halloween Night at Pololu! Including impatient severed fingers, a robotic exorcism baby, and not to mention some stabby silhouettes for your windows!

If you’re new to hacking, Halloween is a great excuse to get started, and [Chuck] has put together an inexpensive animated Halloween decoration that you can show off on your front door. After scoring a $5 plastic Halloween doorknocker from Wal-Mart, [Chuck] gathered together a small pile of components and then set about breathing some life (death?) into its scary but motionless face.

Though he opted to use a Digispark, you should be able to use any Arduino that is small enough to stuff inside the plastic head. [Chuck] cut some holes in the eyeballs and glued in two RGB LEDs, then cobbled together a quick-and-dirty mount in the mouth area to hold a small servo. The lights and the servo are wired to the Digispark, which turns the lights on and instructs the servo to slam the ring against the door. It’s is battery powered and currently has only two settings: on or off. This should be good enough to scare the kids for this year, but [Chuck] has plans to add a much-needed motion sensor and sound via a Bluetooth connection. 

As simple as this build is, it could be just the thing to get you in the holiday spirit, or to introduce the young hacker in your home to the world of electronics and coding. Check out the short video of the doorknocker after the break, then swing by [Chuck's] website for detailed build instructions and his Github for the source code. If you’re having trouble finding this doorknocker at Wal-Mart, [Chuck] recommends a similar one on Amazon. Don’t stop now! Make some Flickering Pumpkins too, or if you want a challenge, hack together your very own Pepper’s Ghost illusion.