[Andy Geppert] sends in his incredibly clever interactive core memory shield. 

In a great display of one hacker’s work being the base for another’s, [Andy] started out with [Jussi Kilpelainen]’s core memory shield for Arduino.  As he was playing with the shield he had a desire to “see” the core memory flipping and got the idea to add an LED matrix aligned behind the individual cores.

The first iteration worked, but it only showed the state that the Arduino believed the core memory to be in. What he really wanted was a live read on the actual state. He realized that an Adafruit Featherwing 8×8 matrix display also fits behind the core memory. Now the LEDs update based on the read state of the core memory. This allows him to flip the individual bits with a magnetic stylus and see the result. Very cool.

You can see a video of it working after the break.

[Amirreza Nasiri] sends in this cool USB keystroke injector.

The device consists of an Arduino, a Bluetooth module, and an SD card. When it’s plugged into the target computer the device loads the selected payload from the SD card, compromising the system. Then it does its unique trick which is to switch the injector over to Bluetooth mode. Now the attacker has much more control, albeit local, over the system.

While we would never even be tempted to plug this device into a real computer, we like some of the additional features, like how an added dip switch can be used to select from up to eight different payloads depending on the required attack. The addition of a photo diode is also interesting, and makes us dream of all sorts of impractical movie hacker scenarios. [Amirreza] says it’s to trigger when the person leaves the room and turns the lights off.

[Amirreza] has all the code and design files on the GitHub. There are also a few payload examples, which should be fun to hack on. After all, one of life’s pleasures is to find new ways to mess with your friends.

A lot of consumer gadgets use touch sensors now. It is a cheap and reliable way to replace a variety of knobs and switches on everything from headphones to automobiles. However, creating a custom touch controller for a one-off project can be daunting. A recent ACM paper shows how just about any capacitive sensor can work as a multitouch sensor with nothing more than an Arduino although a PC running processing interprets the data for higher-level functions.

The key is that the Arduino excites the grid using PWM and then examines the signal coming out of the grid. Finger poking changes the response quite a bit and the Arduino can sense it using the analog to digital converters onboard. You can find the actual software kit online. The tutorial document is probably more interesting than the ACM paper if you only want to use the kit.

The optimum drive frequency is 10 MHz. The examples rely on harmonics of a lower frequency PWM signal to get there. The analog conversion, of course, isn’t that fast but since your finger touch rate is relatively slow, they treat the signal as an amplitude-modulated input which is very easy to decode.

The sensors can be conductive ink, thread, or copper strips. There are several example applications, including a 3D printed bunny you can pet, a control panel on a sleeve, and an interactive greeting card.

The sensor forms an image and OpenCV detects the actual touch configuration. It appears you can use the raw data from the Arduino, too, but it might be a little harder.

We imagine aluminum foil would work with this technique. If you get to the point of laying out a PCB, this might come in handy.

[Will] wanted to build some animatronic eyes that didn’t require high-precision 3D printing. He wound up with a forgiving design that uses an Arduino and six servo motors. You can see the video of the eyes moving around in the video below.

The bill of materials is pretty simple and features an Arduino, a driver board, and a joystick. The 3D printing parts are easy to print with no supports, and will work with PLA. Other than opening up holes there wasn’t much post-processing required, though he did sand the actual eyeballs which sounds painful.

The result is a nice tight package to hold six motors, and the response time of the eye motion is very impressive. This would be great as part of a prop or even a robot in place of the conventional googly eyes.

While the joystick is nice, we’d like to see an ultrasonic sensor connected so the eyes track you as you walk across the room. Maybe they could be mounted behind an old portrait for next Halloween. Then again, perhaps a skull would be even better. If you want a refresher about servos, start with a laser turret tutorial.

Have you ever looked around your city’s layout and thought you could do better? Maybe you’ve always wanted to see how she’d run on nuclear or wind power, or just play around with civic amenities and see how your choices affect the citizens.

[Robbe Nagel] made this physical-digital simulator for a Creative Programming class within an industrial design program. We don’t have all the details, but as [Robbe] explains in the video after the break, each block has a resistor on the bottom, and each cubbyhole has a pair of contacts ready to mate with it. An Arduino nestled safely in the LEGO bunker below reads the different resistance values to determine what block was placed where.

[Robbe] wrote a program that evaluates various layouts and provides statistics for things like population, overall health, education level, pollution, etc. As you can see after the break, these values change as soon as blocks are added or removed. Part of what makes this simulator so cool is that it could be used for serious purposes, or it could be totally gamified.

It’s no secret that we like LEGO, especially as an enclosure material. Dress it up or dress it down, just don’t leave any pieces on the floor.

Via r/Arduino

What can you do with ferromagnetic PLA? [TheMixedSignal] used it to give new meaning to the term ‘musicians’ gear’. He’s made a proof of concept for a DIY tone generator, which is the same revolutionary system that made the Hammond organ sing.

Whereas the Hammond has one tonewheel per note, this project uses an Arduino to drive a stepper at varying speeds to produce different notes. Like we said, it’s a proof of concept. [TheMixedSignal] is proving that tonewheels can be printed, pickups can be wound at home, and together they will produce audible frequencies. The principle is otherwise the same — the protruding teeth of the gear induce changes in the magnetic field of the pickup.

[TheMixedSignal] fully intends to expand on this project by adding more tone wheels, trying different gear profiles, and replacing the stepper with a brushless motor. We can’t wait to hear him play “Karn Evil 9”. In the meantime, put on those cans and check out the demo/build video after the break.

We don’t have to tell you how great Hammond organs are for making music. But did you know they can also encode secret messages?

Via the Arduino blog.

[Tijmen Schep] sends in his project, Candle Smart Home, which is an exhibit of 12 smart home devices which are designed around the concepts of ownership, open source, and privacy.

The central controller runs on a Raspberry Pi which is running Mozilla’s new smart home operating system. Each individual device is Arduino based, and when you click through on the site you get a well designed graphic explaining how to build each device. The devices them

It’s also fun to see how many people worked together on this project and added their own touch. Whether it’s a unique covering for the devices or a toggle switch that can toggle itself there’s quite a few personal touches.

As anyone who’s had the sneaking suspicion that Jeff Bezos was listening in to their conversations, we get the need for this. We also love how approachable it makes hacking your own hardware. What are your thoughts?

Are you waiting for something that may never happen? Maybe it’s the end of your ennui, or the release of Half Life 3. While you wait, why not build a Godot Machine? Then you can diversify your portfolio and wait for two things that could happen today, tomorrow, or at sunrise on the 12th of Never.

The Godot Machine is a functional art piece that uses a solar panel and a joule thief to charge a bank of capacitors up to 5V. Whenever that happens, the Arduino comes online and generates a 20-bit random number, which is displayed on an LED bar. If the generated number matches the super-secret number that was generated at first boot and then stashed away in EEPROM, the Machine emits a victory beep and lights a green LED. Then you can go back to complaining about whatever.

We like that [kajnjaps] made his own chaos-based random number generator instead of just calling random(). It uses a guitar string to collect ambient electronic noise and an entropy generator to amplify it. Then the four least significant digits are used to seed the logistical map, so the initial value is always different.

You don’t have to create your own entropy for truly random numbers, though it’s probably more fun that way. Did you know that someone wrote an Arduino entropy library?

Building a future where robots work alongside humans relies heavily on soft robotics. Typically this means there will be an air compressor or a hydraulic system nearby, taking up precious space. But it doesn’t have to.

Engineers at the UC-San Diego Jacobs School have created a soft robotics system that uses electricity to control flexible actuators, much like our brains move our muscles. It works like this: sheets of heat-sensitive liquid crystal elastomer are sandwiched between two layers of standard elastomer. These layers are rolled into cylinders that can twist and bend in different directions depending on which of its six element(s) get electricity. Light up all six, and the tube contracts, forming the foundation for a good gripper. The team also built a tiny walker, pictured above.

The project is still in its infancy, so the actuators are slow to bend and even slower to return to their original shape, but it’s still a great start. Imagine all the soft robotic projects that can get off the ground without being shackled by the bulk and weight of an air compressor or fluid handling system. Watch it do various sped-up things after the break, like claw-machine gripping a bottle of chocolate rocks.

Speaking of delicious candy, edible soft robotics is totally a thing.

Via Arduino blog

[Miller] wanted to practice a bit with some wireless modules and wound up creating a robotic hand he could teleoperate with the help of a haptic glove. It lookes highly reproducible, as you can see the video, below the break.

The glove uses an Arduino’s analog to digital converter to read some flex sensors. Commercial flex sensors are pretty expensive, so he experimented with some homemade sensors. The ones with tin foil and graphite didn’t work well, but using some bent can metal worked better despite not having good resolution.

The wireless communications set up was pretty easy thanks to the NRF24L01 modules. The hard part was sewing the flex sensors into the glove. We thought some of the circuitry looked precarious on the glove, too.

For the robot hand, he used balsa wood and hinges for each joint. Flexible thread provided the return power like a spring. The hand was surprisingly artistic in a primitive sort of way.

While this is a cool demo, the hand isn’t likely to be practical for much as it is. Nerve impulses are better but harder. The glove reminded us a little of one we’d seen before.