Nerf guns can be a lot of fun, but what if you want your launcher to shoot 10 projectiles simultaneously? Is so, then look no further than James Bruton’s custom blaster.

His 3D-printed project employs two BLDC-powered rollers to accelerate cartridges of 10 darts each, and allows for quick reloading via a clever manual locking mechanism. The device holds five magazines, for total of 50 darts.

When loaded, an arcade-style button fires the darts, pushing them into the rollers at the same time using a couple of servo motors. Everything is powered by a six-cell 24V LiPo battery, while an Arduino Mega is used for control, and to track which cartridge is in place, enabling the operator to concentrate on getting shots downrange!

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.

[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.

SCARA robots are often used in industrial settings to move components in the proper location. In order to demonstrate the concept to students, Nicholas Schwankl has come up with a simple unit that employs three servos and 3D-printed parts to dispense 4.5mm bearings.

The device runs on an Arduino Mega (though an Uno or other model would work) and as seen in the video below, it twists its ‘shoulder’ and ‘elbow’ joint to position its dispenser tube. Once in place, a micro servo releases a bearing, allowing the tiny steel ball to drop into an empty slot.

STL files, a parts list, and Arduino code are available in the Schwankl’s write-up.

Perler beads allow you to make fun designs by melting these tiny colored objects together, but why arrange them by hand when you can have a machine do it for you? That’s the idea behind this hack by YouTuber knezult11, where a non-working 3D delta printer is heavily modified to dispense beads instead of filament.

The setup uses a Python program to analyze any image and select between the machine’s array of 64 bead colors for pixels, while control of the system itself is accomplished with the help of two Arduino boards.

Perlers are fed using tubes and mechanical actuators, creating beautiful sprites without the tedium of placing every single bead. Once done “printing,” the machine’s heated bed fuses the result together rather than the typical ironing method.

To help a patient in his country with a congenital limb deficiency, Buzi Nguyen has designed a 3D-printed transhumeral—above the elbow—prosthesis prototype. The device features 10 degrees of freedom, including independent control of four fingers and a thumb, along with movement capabilities for the wrist and forearm.

The prosthesis is powered by a number of Arduino boards and a Raspberry Pi, and equipped with computer vision to track and choose grip patterns for object handling. It can also potentially be operated via brain-computer interface and electromyography.

A demonstrate of all the currently supported features can be seen in the video below.

While computer printers are readily available, if you’d like a plotting device that drags a pen, marker, or whatever you need across paper to create images, your options are more limited. To fill this gap, studioprogettiperduti has come up with the d.i.d, or Deep Ink Diver.

This scalable pen plotter uses a frame made out of 3D-printed parts, as well as aluminum extrusion, which could be lengthened to support the size of paper that you need. A timing belt pulls the writing carriage back and forth, while a roller advances the paper. 

Control is handled by an Arduino Uno and a CNC shield, with a version of grbl that accommodates a servo used to lift the pen.

The materials and electronics used for the plotter are all standard and easy to source. The main frame is made of aluminum extrusion and 3D-printed connections. The motors are all standard NEMA 17 stepper motors and a single SG-90 servo motor. Everything is driven by a cheap Arduino Uno control board that handles the transition from g-code to movement. Furthermore, the software used to create G-code, Inkscape, is open source as well.

LEDs are fun, and RGB(W)s adds a new element to things, but what if you want a light that can also move by itself? The Mover3D does just that as a pan/tilt system controlled by the DMX512 communication protocol. You simply feed instructions in via any standard lighting console, and it dances around under your commands.

The 3D-printed device uses an Arduino Uno inside the fixture’s base to send signals to an RGBW LED, as well as control a pair of servo motors that pan and tilt the light turret. While light output is limited for now, a second version featuring a 14,000 lumen output with stepper motors and slip rings for 360° rotation is in the works, and should be quite impressive when it’s done! 

Setup and programming instructions can be found in the project’s write-up, and needed print files are up on Thingiverse.

Sure, we’ve seen low-cost DIY 3D printers with wooden frames before, but not a 3D printer that actually ‘prints’ wood. That’s exactly what Shane Wighton and his Formlabs hackathon team have done. (Although probably more along the lines of a hybrid additive/subtractive CNC machine that makes parts out of 3/4″ plywood.)

The device first cuts each layer out with a router, applies glue automatically, and then feeds subsequent layers onto a stack to be cut in the same manner. The result of these combined layers is a block of wood with a very large “benchy” inside, revealed with a bit of manual cutting.

Motion control is handled by an Arduino Due, which interfaces with a number of stepper drivers to move the router, while an off-the-shelf relay board triggers the pneumatics, lights, and even a horn to indicate when a job is complete.

More details on the build are available in Wighton’s write-up here and you can see it in action below!

As you experiment with Arduino boards and programming, you’ll likely have ideas that you want to test right now. Unfortunately, you can’t always have the entire project with you to try out. With that in mind, Khang Nguyen has designed the Portable Arduino Bot.

This sci-fi-inspired device packs an Arduino Nano inside, along with an on/off switch, a microswitch, three LEDs, and a LiPo battery for power. To protect these components, the bot features a nice 3D-printed enclosure, complete with foldable feet that make it look like a small robot or even spaceship. 

While it won’t replace all the tools you have at home, it appears to be a great way to carry out testing, and as shown in the videos below, to play sounds with the addition of a buzzer!