Planet Arduino

Ever wanted your own gesture-controlled robot arm? [EbenKouao]’s DIY Arduino Robot Arm project covers all the bases involved, but even if a robot arm isn’t your jam, his project has plenty to learn from. Every part is carefully explained, complete with source code and a list of required hardware. This approach to documenting a project is great because it not only makes it easy to replicate the results, but it makes it simple to remix, modify, and reuse separate pieces as a reference for other work.

[EbenKouao] uses a 3D-printable robotic gripper, base, and arm design as the foundation of his build. Hobby servos and a single NEMA 17 stepper take care of the moving, and the wiring and motor driving is all carefully explained. Gesture control is done by wearing an articulated glove upon which is mounted flex sensors and MPU6050 accelerometers. These sensors detect the wearer’s movements and turn them into motion commands, which in turn get sent wirelessly from the glove to the robotic arm with HC-05 Bluetooth modules. We really dig [EbenKouao]’s idea of mounting the glove sensors to this slick 3D-printed articulated gauntlet frame, but using a regular glove would work, too. The latest version of the Arduino code can be found on the project’s GitHub repository.

Most of the parts can be 3D printed, how every part works together is carefully explained, and all of the hardware is easily sourced online, making this a very accessible project. Check out the full tutorial video and demonstration, embedded below.

3D printing has been a boon for many projects, especially those involving robotic arms. All kinds of robotic arm projects benefit from the advantages of 3D printing, from designs that focus on utility and function, to clever mechanical designs that reduce part count in unexpected ways.

People get into electronics for all kinds of reasons, but we would guess that the ability to blink the blinkenlights is probably pretty high on the survey results. [Kuchbert] has been going to Deichkind shows for the last decade and has wanted to build one of the German techno-rap band’s signature tetrahedral LED hats for about as long.

Up inside the hat is an Arduino Nano driving WS2812B LEDs and a portable battery to power everything. Thanks to an HC-05 Bluetooth module, the show can be controlled with an Android app. The many, many holes in the acrylic panels were milled out, but they could just as easily be laser-cut, or if you have infinite patience, drilled by hand. The code is coming once it has been cleaned up a bit. Everything else you’d need is already there waiting. This helmet even has its own lil’ music video, which we’ve carefully beat-matched in after the break.

Naturally, this makes us think of all the Daft Punk helms that have blinked by on this blog over the years. This hand-soldered one might be the most meticulously made.

If you have a small logistics problem, we have the solution for you. [Leon] built a tiny little forklift with LED lighting, working forks, and remote control using a combination of 3D printing tech, some CNC work, and fine soldering skills.

The electronics for this build are based around a few servos and a pair of geared DC motors and are driven via an Arduino Mega. Connectivity and remote controllability are what you would expect from an Arduinified project. There’s an HC-05 Bluetooth module on the board and remote control is handled by a custom Android app.

Of note in this project are the forks that actually work, almost like a real forklift. This allows the mini Arduino forklift to pick up mini pallets, drop them somewhere, and have mini DIY enthusiasts come up to build mini-furniture for mini-Etsy, which will be prominently featured in the mini foyer of a mini two-story walkup. No, it’s not mini-gentrification; this mini forklift is helping the mini local economy.

You can check out the entire build video below, filmed in the usual maker demo method of speeding up the entire build process but somehow keeping the no-talking audio. We have a lot to thank [Jimmy DiResta] for, and it’s not just cinematography. All the files for this forklift are up on the Github should you want to build your own.

Tank projects are great because while every tank design is the same in a fundamental way, there’s nevertheless endless variety in the execution and results. [Hoo Jian Li]’s 3D Printed Tank is smartly laid out and has an unusual tank tread that shows off some slick curves.

The tank itself is remotely controlled over Bluetooth with a custom controller that uses the common HC-05 Bluetooth radio units. The treads are driven by four hobby gearmotors with custom designed wheels, and run over an idler wheel in the center of the body. There isn’t any method of taking up slack in the track and a ripple in the top surface of the track is visible as it drives, but the tank is small enough that it doesn’t seem to mind much. STL files and source code is available on GitHub; unfortunately the repository lacks a wiring diagram but between the low component count, photos, and source code that’s not a show-stopper.

Tank treads see a lot of variation, from 3D printed designs for tracks that use a piece of filament as hinges to an attempt to use a conveyor belt as a tank tread for a go-kart. Some tank projects even eschew treads altogether and go for a screw drive.

Tired of risking his life every time he had to signal a turn using his hands while riding his bicycle in rainy Vancouver, [Simon Wong] decided he needed something a bit higher tech. But rather than buy something off the shelf, he decided to make it into his first serious Arduino project. Given the final results and the laundry list of features, we’d say he really knocked this one out of the park. If this is him getting started, we’re very keen to see where he goes from here.

So what makes these turn signals so special? Well for one, he wanted to make it so nobody would try to steal his setup. He wanted the main signal to be easily removable so he could take it inside, and the controls to be so well-integrated into the bike that they wouldn’t be obvious. In the end he managed to stuff a battery pack, Arduino Nano, and an HC-05 module inside the handlebars; with just a switch protruding from the very end to hint that everything wasn’t stock.

On the other side, a ATMEGA328P microcontroller along with another HC-05 drives two 8×8 LED matrices with MAX7219 controllers. Everything is powered by a 18650 lithium-ion battery with a 134N3P module to bring it up to 5 VDC. To make the device easily removable, as well as keep the elements out, all the hardware is enclosed in a commercial waterproof case. As a final touch, [Simon] added a Qi wireless charging receiver to the mix so he could just pull the signal off and drop it on a charging pad without needing to open it up.

It’s been some time since we’ve seen a bike turn signal build, so it’s nice to see one done with a bit more modern hardware. But the real question: will he be donning a lighted helmet for added safety?

[smash_hand] had a clear goal: a big, featureless, white plastic disk with RGB LEDs concealed around its edge. So what is it? A big ornament that could glow any color or trippy mixture of colors one desires. It’s an object whose sole purpose is to be a frame for soft, glowing light patterns to admire. The disk can be controlled with a simple smartphone app that communicates over Bluetooth, allowing anyone (or in theory anything) to play with the display.

The disk is made from 1/4″ clear plastic, which [smash_hand] describes as plexiglass, but might be acrylic or polycarbonate. [smash_hands] describes some trial and error in the process of cutting the circle; it was saw-cut with some 3-in-1 oil as cutting fluid first, then the final shape cut with a bandsaw.

The saw left the edge very rough, so it was polished with glass polishing compound. This restores the optical properties required for the edge-lighting technique. The back of the disc was sanded then painted white, and the RGB LEDs spaced evenly around the edge, pointing inwards.

The physical build is almost always the difficult part in a project like this — achieving good diffusion of LEDs is a topic we talk about often. [smash_hands] did an impressive job and there are never any “hot spots” where an LED sticks out to your eye. With this taken care of, the electronics came together with much less effort. An Arduino with an HC-05 Bluetooth adapter took care of driving the LEDs and wireless communications, respectively. A wooden frame later, and the whole thing is ready to go.

[smash_hands] provides details like a wiring diagram as well as the smartphone app for anyone who is interested. There’s the Arduino program as well, but interestingly it’s only available in assembly or as a raw .hex file. A video of the disk in action is embedded below.

Making LED lighting interactive comes in many different shapes and forms, and as the disk above shows, shifting color patterns can be pleasantly relaxing.

After you’ve taken a moment to ponder the turn of phrase used in the title, take a look at this scratch-built robotic vacuum created by [theking3737]. The entire body of the vacuum was 3D printed, and all of the internal electronics are off-the-shelf modular components. We can’t say how well it stacks up against the commercial equivalents from iRobot and the like, but it doesn’t look like it would be too hard to build one yourself to find out.

The body of this rather concerned-looking robot was printed on a DMS DP5 printer, which is a neat trick as it only has a build platform of 200 mm x 200 mm. Once all the pieces were printed, a 3D pen was used to “weld” the sections together. The final result looks a bit rough, but should give a bond that’s just as strong as the printed parts themselves.

The robot has four sets of ultrasonic range finders to detect walls and obstacles, though probably not in the positions you would expect. The right side of the robot has two sets of sensors, while the left side only gets one. We aren’t sure the reasoning behind the asymmetrical layout, but presumably the machine prefers making right turns.

Control is provided by an Arduino Mega and the ever-reliable HC-05 Bluetooth module. A companion Android application was written which allows configuring the robot without having to plug into the Arduino every time you want to tweak a setting.

We can’t say we’ve seen that many DIY robotic vacuums here at Hackaday, but we’ve certainly featured our fair share of hacks for the commercially available models.

Whether it’s our own cat or a neighbor’s, many of us have experienced the friendly feline keeping us company while we work, often contributing on the keyboard, sticking its head where our hands are for a closer look, or sitting on needed parts. So how to keep the crafty kitty busy elsewhere? This roboticized laser on a pan-tilt mechanism from the [circuit.io team] should do the trick.

The laser is a 650 nm laser diode mounted on a 3D printed pan-tilt system which they found on Thingiverse and modified for attaching the diode’s housing. It’s all pretty lightweight so two 9G Micro Servos do the grunt work just fine. The brain is an Arduino UNO running an open-source VarSpeedServo library for smooth movements. Also included are an HC-05 Bluetooth receiver and an Android app for controlling the laser from your phone. Set it to Autoplay or take a break and use the buttons to direct the laser yourself. See the video below for build instructions and of course their cat, [Pepper], looking like a Flamenco dancer chasing the light.

Think your cat might get bored chasing a light around by itself? Mount the laser on a mobile robot with added IR proximity sensor which can roll around and play with the cat.

[DastardlyLabs] saw a video about converting a PS/2 keyboard to Bluetooth and realized he didn’t have any PS/2 keyboards anymore. So he pulled the same trick with a USB keyboard. Along the way, he made three videos explaining how it all works.

The project uses a stock DuinoFun USB mini host shield with a modification to allow it to work on 5V. An Arduino mini pro provides the brains. A FT-232 USB to serial board is used to program the Arduino. A standard Bluetooth module has to have HID firmware installed. [Dastardly] makes a homemade daughterboard–er, shield–to connect it to the Arduino.

The result is a nice little sandwich with a USB plug, a Bluetooth antenna, and some pins for reprogramming if necessary. Resist the urge to solder the Bluetooth board in–since it talks on the same port as the Arduino uses for programming, you’ll have to remove it before uploading new code.

If you need help reprogramming the HC-05 Bluetooth module, we’ve covered that before. This project drew inspiration from [Evan’s] similar project for PS/2 keyboards.

Chromecasts are fantastic little products, they’re basically little HDMI sticks you can plug into any monitor or TV, and then stream content using your phone or computer as the controller. They are powered by a micro USB port in the back, and if you’re lucky, your TV has a port you can suck the juice off. But what if you want to turn it off while you use a different input on your TV? You might have to build a power switch.

Now in all honesty, the Chromecast gets hot but the amount of power it draws when not in use is still pretty negligible compared to the draw of your TV. Every watt counts, and [Ilias] took this as an opportunity to refine his skills and combine a system using an Arduino, Bluetooth, and Android to create a robust power switch solution for the Chromecast.

The setup is rather simple. An HC-05 Bluetooth module is connected to an Attiny85, with some transistors to control a 5V power output. The Arduino takes care of a bluetooth connection and uses a serial input to control the transistor output. Finally, this is all controlled by a Tasker plugin on the Android phone, which sends serial messages via Bluetooth.

All the information you’ll need to make one yourself is available at [Ilias’] GitHub repository. For more information on the Chromecast, why not check out our review from almost three years ago — it’s getting old!