If you’ve ever wished you could levitate tiny drops of liquid, small solids, or insects in mid-air, new research has you covered. That’s because Asier Marzo, Adrian Barnes, and Bruce W. Drinkwater have developed a 3D-printed, Arduino Nano-controlled acoustic levitator.
Their device uses two arrays of 36 sonic transducers in a concave pattern, which face each other in order to suspend objects like Styrofoam, water, coffee and paper in between. Several items can even be trapped at the same time, and liquid is inserted into the “levitation zone” via a syringe.
The principle is similar to the vibration you feel when next to a large speaker, but in this case, the homemade levitator employs ultrasonic waves to push particles without causing any damage to humans.
Acoustic levitation has been explored in hundreds of studies for applications in pharmaceuticals, biology or biomaterials. It holds the promise of supporting innovative and ground-breaking processes. However, historically levitators have been restricted to a small number of research labs because they needed to be custom-made, carefully tuned and required high-voltage. Now, not only scientists but also students can build their own levitator at home or school to experiment and try new applications of acoustic levitation.
If you suppose that electromagnetically-propelled projectiles are strictly the purview of well-funded government research labs, think again! Using two sets of coils wrapped around custom 3D-printed base structures and an Arduino Nano for control, YouTuber “Gyro” created his own coilgun capable of propelling steel fast enough to dent a piece of wood.
When fired, a photodiode at the end of each electromagnet coil sends a signal to the Arduino. This, in turn, shuts off the coil, allowing it freely escape the barrel.
As noted in his Instructables write-up, the gun is constructed without large capacitors, which can be expensive and dangerous. Instead, two LiPo battery packs are combined to produce around 22 volts, though this and the number of coils used, could be increased to produce a more powerful device!
You may be familiar with “Pop-A-Shot” at arcades and amusement parks, which allows you to shoot baskets at a hoop for fun and prizes. Maker Cory Guynn, apparently unsatisfied with not having one of these at home, decided to duplicate the game with the “Pop o Shop.”
In this version, an ultrasonic sensor in the hoop tells an Arduino Nano when a shot has been registered, while two 7-segment displays inside of a LEGO scoreboard show the current count, time remaining, and high score. There is also an RGB LED that turns green after every made basket and changes color with a new top score.
Incidentally, one of the displays can also spell out “POPOSHOP,” which dictated the name of the game, since there is no “T” character in the LedControl library used! For more info and code, be sure to check out the “Internet of LEGO” build log!
Usually, when you think of doing “surgery” on electronics, it’s to replace a component, or maybe modifying an appliance into something different. In this case, an Arduino Nano powers Hurry, Doctor!, an updated version of the board game classic Operation meant as a middle school STEM exercise.
This game, of which creator “TrevorB23” gives an extensive explanation in his Instructables write-up, features a LEGO minifigure with cutouts inside that house obstructions such as a “mental block” and “funny bone.” As with the original, the objective is to remove these foreign bodies without touching the sides, constructed here with conductive aluminum foil tape in order to signal the Nano.
With its enhanced electronics, TrevorB23’s version adds a timing element to encourage “surgeons” to complete tasks faster, as well as doctor names and melodies that can be altered if so desired. Want to make your own game? You can follow along with his 31-step tutorial.
As entertaining as watching Netflix may be, you’re not burning a lot of calories while binging on your favorite shows. In order to do both at the same time, hacker “Roboro” modded a stationary exercise bike to stop streaming if he’s not maintaining his fitness goals.
Bicycle speed is derived from the signal that’s normally sent to the built-in display. He uses an Arduino Nano to hijack the square wave, and sends this info to the streaming computer serially via USB.
Starting the Python script and inputting some information, Firefox will start to stream Netflix and display in real-time for current workout information such as round, speed, nominal speed for this round and time to next round. If the user goes below the nominal speed for too long, Netflix will pause until the user has gotten back up to speed.
After building a bicycle that could travel across town while making music, Sam Battle now taken things in a different direction. Synth Bike 3.0, which will be on display at the Science Center Dublin until September, is set up on a training fixture so that you can pedal it indoors rain or shine. This version also features a simplified control panel on the handlebars, allowing it to be played by anyone at a tempo controlled by the rear wheel’s speed.
Battle’s YouTube channel is named “LOOK MUM NO COMPUTER” however, this apparently doesn’t count microcontrollers. Hidden in the externally clean-looking handlebar groove box is a total of 12 Arduino Nano boards, along with a maze of wiring, strip circuit boards, frequency central PCBs, a SparkFun WAV trigger, and some other electronics. There’s even built-in speakers on the sides to output the created sounds.