Small is often subjective. For example, a school bus is small compared to an Airbus A380. But other things are just small all on their own and need no comparison to make the point. Such is the case with this micro RC car in the video below the break. It’s an RC model of the Smart Car, that when compared to other vehicles on the road, is quite diminutive, both subjectively and absolutely. But the outward appearance of [diorama111]’s project only tells half the story.
Starting out as a static display model, [diorama111] fully disassembled the 1/87 scale Smart Car and got to work. Fully proportional steering is attained with a very, very small stepper motor that drives custom knuckles attached to handmade suspension. They are works of art in their own right.
Drive is supplied by another small stepper motor. If [diorama111] had stopped there, it would have been every bit as noteworthy to see a 1/87 Smart Car doing figure eights around small bottles of model paint. Instead, [diorama111] kept going! The car has working turn signals, brake lights (including the 3rd taillight in the back window!) and headlights. There is even a function for hazard lights.
The electronics are all hand built using enameled wire and SMD components on perf board, and are a study in miniaturization all their own. An ATtiny processor seems right at home in this design. We admire [diorama111]s steady hands and patience to build such a small RC car, never mind one with such fine attention paid to all the details.
When the remote for your son’s RC car goes missing, what are you going to do? Throw away a perfectly good robot chassis? No, we wouldn’t either. And these days, with WiFi-enabled microcontroller boards so readily available, it’s almost easier to network the thing than it would be to re-establish radio control. So that’s just what [Stian Søreng] did.
Naturally, there’s an ESP8266 board at the heart of this hack, a WeMos D1 to be specific. [Stian] had played with cheap remote-controlled cars enough to be already familiar with the pinout of the RC IC, so he could simply hook up some GPIOs from the WeMos board to the pins and the brain transplant was complete.
On the software side, he implemented control over TCP by sending the characters “F”, “B”, “L”, or “R” to send the car forward, back, left, or right. Lowercase versions of the same letters turns that function off. He then wrote some client software in Qt that sends the right letters. He says that response time is around 150-250 ms, but that it works for his driving style — crashing. (We’d work on that.)
Anyway, it’s a fun and fairly quick project, and it re-uses something that was destined for the junk heap anyway, so it’s a strict win. The next steps are fairly open. With computer control of the car, he could do anything. What would you do next?
Does your RC car’s crude, push-button controller make you feel like you’re mashing tv remote buttons like a caveman? We think so too, but [Noel] has actually done the heavy-lifting to fix just that. He’s revamped his kids’ rc controller for gesture control. Now their rc car can be guided by the crisp, intuitive control of one’s wrist movements.
To tackle this project, [Noel] has integrated a gyroscope and accelerometer, an Arduino, and the existing remote. Data from the gyroscope-and-accelerometer limits are mapped to the buttons through an Arduino, which parses the raw data and triggers the controller’s switches, now wired directly to the Arduino and pulled up with resistors. In his overview video, [Noel] tells us that he’s binarized the gyroscope-and-accel data to trigger at certain limits, a choice that adequately suits the controller’s original push-button controls. Finally, the entire setup is cleanly strapped to a 3D-printed case. Not bad, for a grand total of $20 and a quick trip to Target.
[Noel]’s custom wrist-controller takes its place on the shelf of many other unique controllers, and his demo is a great example of using existing open hardware to tailor our toys to more personal tastes. After all, the hardware shopping list is just a breakout board, an Arduino, and a few jumper wires. When the next zombie apocalypse hits, we can easily see some practical components like these making their way into our suitcase. At the very least, we’ll be able to build a few wrist controllers and dispatch some toy cars to greet the undead.
First you’ll have to hack apart one of those little 1/64 scale RC cars you can get for a few dollars, and then all you need are a few household supplies, and a helium filled balloon. [Masynmachien] says the total cost of this project can be as little as $13 — depending on where you get your supplies.
So how does it work? Well, an 11″ helium filled party balloon can lift about 10g quite easily — if you strip away the body and chassis of one those RC cars you’ll be well under that weight. The RC cars typically have one small DC motor and a steering actuator, but [Masynmachien] found you can actually connect a second DC motor to the leads for the actuator and it works just fine. Doing this you can create a main prop to drive the blimp, and a secondary tail rotor to steer it. The Instructable uses mostly recycled components, but we’re sure if you had more time you could design and build an even nicer one. When the blimp is properly trimmed it sinks slowly in the air, so the main prop is responsible for keeping it at a certain altitude — this takes a bit of getting used to but it’s an easy way to get around steering in all directions.