The donor keyboard is a nondescript late-80s AT compatible PC. Before readers imagine that a sought-after mechanical ‘board is being defiled, these were manufactured in their millions back then with exactly the same lackluster actions as modern cheap input devices. This one had plenty of space inside for an Arduino Nano that emulates an AT keyboard host and plays WAV file samples from an SD card to one of its PWM outputs. An op-amp low pass filter cleans up the noise from this rudimentary DAC, and feeds a little speaker through an audio amplifier. The keyboard supports both male and female voices, as well as a piano.
Hours of juvenile fun will no doubt result, but we can’t help wondering whether this could become the bane of a parent’s life in the manner of so many other noise-producing toys. Meanwhile, [Peter]’s work has graced these pages in the past, most recently with an automatic cooker hood.
Rocket League is a video game famous for being wildly popular despite being virtually unplayable without several hours practice. It involves hyper fast cars playing soccer, complete with the ability to flip, jump, and rocket boost into the ball. [mrak_ripple] decided he wanted some of that action in a real RC car, and set to work.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
The final result is impressive, with the car flipping relatively cleanly once refined and lightened from its original design. We’d love to see a two-axis build that can front- and back-flip as well. It’s a step up in complexity from the last build we saw from [mrak_ripple], the amusing mashed potato trebuchet. Video after the break.
While VR is becoming really immersive, it still can’t compete with a game of good old laser tag to get the blood pumping and spending quality time with friends. [Xasin] has been working on a DIY laser tag system for a while now, and it has grown to include an impressive array of features and customizability.
Named LZRTag, the project started back in 2018 with simple ATmega328 based prototypes on breadboards. It has since evolved to a fully-featured system with ESP32s in the 3D printed pistol communicating with a Raspberry Pi/Linux game server over MQTT. Each pistol also features an accelerometer, I2S audio amp and speaker for game sounds, and WS2812 RGP LEDs for light effects. IR Lasers are used as emitters to target wearable IR receivers with more RGB LEDs wired to the pistol.
A Ruby server on a Linux machine takes care of all the communications, game management, shot validation, and scoring. It can handle up to 255 players and is designed to be extremely customizable for game modes, weapons classes, or any other feature you would like to have. [Xasin] has also created IR beacons to add even more possibilities, such as capture the flag, safe zones, and revive zones.
A red ball travels through a network of clear acrylic tubes using 3D printed Venturi air movers, gravity, and toys to help it travel. Spectators can change the ball’s path with their phones via a local website with a big picture of the installation. The ball triggers animations along its path using break beam detection and weaves a different story each time depending on the toys it interacts with.
Here’s how it works: a Raspberry Pi 4 is responsible for releasing the ball at the beginning of the track and for controlling the track switches. The Pi also hosts a server for smartphones and the 25 Arduino Nanos that control the LEDs and servos of the animatronics. As a bonus animatronic, there’s a giant whiteboard that rotates and switches between displaying the kids’ drawings and the team’s plans and schematics. Take a brief but up-close tour after the break.
This awesome art project was a huge collaborative effort that involved the people of Wolfsburg, Germany — families in the community donated their used and abandoned toys, groups of elementary school kids were brought in to create stories for the toys, and several high school kids and other collaborators realized these drawings with animatronics.
Many hackers learned about electronics over the years with home experimenter kits from Radio Shack and its ilk. Eschewing soldering for easier screw or spring based connections, they let the inexperienced build circuits with a minimum of fuss, teaching them the arcane ways of the electron along the way. [victorqedu] has put a modern spin on the form, with his Electric Puzzle Game.
The build consists of a series of 3D printed blocks, each containing a particular electronic component or module. The blocks can be joined together to form circuits, with magnets in the blocks mating with screws in the motherboard to hold everything together and make electrical contact between the parts. It’s a project that requires a significant amount of 3D printing and upfront assembly to build, but it makes assembling circuits a cinch.
The variety of circuits that can be built is impressive. [victorqedu] shows off everything from simple LED and switch arrangements to touch sensors and even a low-powered “Tesla coil”. We imagine playing with the blocks and snapping circuits into place would be great fun. We’ve seen other unconventional approaches before, too – such as building squishy circuits for educational purposes. Video after the break.
Motorsport became obsessed with aerodynamics in the middle of the 20th century. Moving on from simple streamlined shapes, designers aimed to generate downforce with wing elements in order to get more grip between the tyres and the track. This culminated in the development of active aero, where wing elements are controlled by actuators to adjust the downforce as needed for maximum grip and minimum drag. Recently, [Engineering After Hours] decided to implement the technology on his Traxxas RC car.
The system consists of a simple multi-element front wing, chosen for its good trade-off between downforce and drag. The wing is mounted to a servo, which varies the angle of attack as the car’s pitch changes, as detected by a gyroscope. As the car pitches up during acceleration, the angle of the wing is increased to generate more downforce, keeping the nose planted.
The basic concept is sound, though as always, significant issues present themselves in the implementation. Small bumps cause the system to over-react, folding the wing under the front wheels. Additionally, the greater front downforce caused over-steer, leading to the install of a rear wing as well for better aero balance.
Regardless of some hurdles along the way, it’s clear the system has potential. We look forward to the next build from [Engineering After Hours], which promises to mimic the fan cars of the 70s and 80s. If you’re looking to improve aero on your full-size car, we’ve got a guide to that too. Video after the break.
There’s a good chance you already saw SpaceX’s towering Starship prototype make its impressive twelve kilometer test flight. While the attempt ended with a spectacular fireball, it was still a phenomenal success as it demonstrated a number of concepts that to this point had never been attempted in the real world. Most importantly, the “Belly Flop” maneuver which sees the 50 meter (160 foot) long rocket transition from vertical flight to a horizontal semi-glide using electrically actuated flight surfaces.
Finding himself inspired by this futuristic spacecraft, [Nicholas Rehm] has designed his own radio controlled Starship that’s capable of all the same aerobatic tricks as the real-thing. It swaps the rocket engines for a pair of electric brushless motors, but otherwise, it’s a fairly accurate recreation of SpaceX’s current test program vehicle. As you can see in the video after the break, it’s even able to stick the landing. Well, sometimes anyway.
Just like the real Starship, vectored thrust is used to both stabilize the vehicle during vertical ascent and help transition it into and out of horizontal flight. Of course, there are no rocket nozzles to slew around, so [Nicholas] is using servo-controlled vanes in the bottom of the rocket to divert the airflow from the motors. Servos are also used to control the external control surfaces, which provide stability and a bit of control authority as the vehicle is falling.
As an interesting aside, Internet sleuths looking through pictures of the Starship’s wreckage have noted that SpaceX appears to be actuating the flaps with gearboxes driven by Tesla motors. The vehicle is reportedly using Tesla battery packs as well. So while moving the control surfaces on model aircraft with battery-powered servos might historically have been a compromise to minimize internal complexity, here it’s actually quite close to the real thing.
Unfortunately, the RC Starship made a hard landing of its own on a recent test flight, so [Nicholas] currently has to rebuild the craft before he can continue with further development. We’re confident he’ll get it back in the air, though it will be interesting to see whether or not he’s flying before SpaceX fires off their next prototype.