Adnan.R.Khan recently decided to give his room’s sliding door latch an upgrade by designing a mechanism to open and close it, using little more than an Arduino Uno and Bluetooth module.
His automated device is operated via a smartphone app written in MIT App Inventor, and it employs a shield to control a small DC motor. The motor then pulls a cable wrapped around two pulleys in order to move the simple barrel latch in or out.
It’s an amazing display of what can be done with parts at hand and basic tools, and could certainly inspire other home security hacks. Be sure to check out the build process and the setup in action below!
Desk chairs are essential tools for the office environment, so why not turn them into a computer input and feedback device? Aarnio, by researchers from several universities, adds this functionality via an Arduino board. It’s able to detect rotation and tilt via an MPU-6050 IMU, and how far it travels along the floor with an optical sensor from a computer mouse.
User feedback is provided by servo motors that can lock individual casters down. A brake setup is also implemented to inhibit rotation of the central axis and a spring is tightened as needed to modify tilt force.
Testing showed about a 90% feedback recognition in users, and applications could include use as a gaming controller or as an assistive device for those with limited mobility of their hands.
When you need to test a single servo, it’s a fairly straightforward task. Just hook it up to an Arduino to generate the proper PWM signal, along with an appropriate power supply, and you’re in business. If, however, you need to test a bunch of them at the same time, things get a bit more complicated.
To solve this challenge for another project he’s working on, Will Cogley built a 3D-printed tester capable of experimenting with 16 servos at the same time.
The device runs on an Uno, and uses four potentiometers and two buttons for controlling the motors in sets of four. Settings from all 16 outputs are displayed on a 1.8” TFT screen and an Adafruit 16-channel driver is implemented to interface with the servos directly.
Infinity cubes use six mirrors arranged in such a way that they bounce light inside back and forth, making them appear to stretch on to infinity. While not the first to make such a device, Thomas Jensma created the frame for his as a single 3D-printed piece.
This method meant that the plexiglass mirrors surrounding the build are automatically quite flat, allowing the 144 LEDs inside to reflect beautifully with no adjustment. An external Arduino board controls the lights, producing an infinite number of patterns. A 5V supply is also used in order to power the assembly.
Instructions for the project can be found here, and with this simplified design, Jensma was able to construct his in a day for just $25 in parts.
If you’d like to build your own vaguely humanoid robot, but don’t care about it getting around, then look no farther than Aster.
The 3D-printed bot is controlled by an Arduino Uno, with a servo shield to actuate its 16 servo motors. This enables it to move its arms quite dramatically as seen in the video below, along with its head. The legs also appear to be capable of movement, though not meant to walk, and is supported with a column in the middle of its structure.
Aster’s head display is made out of an old smartphone, and in the demo it shows its eyes as green geometric objects, an animated sketch, and then, somewhat shockingly, as different humans. Print files for the project are available here and the design is actually based on the more expensive Poppy Humanoid.
Like most one-year-olds, CodePanda’s son really likes pushing buttons. Rather than purchasing a so-called busy board that might teach him skills like unlocking doors or plugging in electrical outlets, he decided to build his own custom device controlled by an Arduino Uno.
The resulting toy features a wide variety of lights, buttons and switches, and makes sounds to keep the little guy entertained. In the center, a big green button activates an analog voltmeter, which not only looks cool, but actually indicates the battery level of the unit.