You Can 3D Print Your Own RC Motorbikes

September 11, 2021 by Lewin Day 4 Comments

Radio control cars have been a popular toy for decades, but their motorcycle counterparts have always lagged behind due to balance issues and compromised agility. At the same time, a little toy motorbike can be mesmerizing in action. [brettt3] built a few of his own design that look remarkably fun to play with.

Modeled after the Ducati Draxter and Suzuki GSX-RR, the 3D printed bodies do a great job of aping their full-size counterparts. With a lick of paint and some finer touches, these could be absolutely exquisite, but they look awesome in the bare plastic nonetheless. The bikes use a belt drive to deliver power from a motor in the body to the rear wheel. To keep them upright, a weighted front wheel is used as a passive gyroscope for stabilization.

But the finest touch is arguably the rider which sits atop each motorcycle. Articulated and with hands resting on the handlebars, the rider moves with the steering of the bike, creating an eerie realism that we can’t get enough of. There’s even a tiny micro-servo in the head which allows the rider to swivel and look in the direction of motion as you’d expect.

Files are available for those wishing to recreate these designs at home. Alternatively, dive deeper into gyro-stabilised designs to learn more about how it all works. Video after the break.

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Re-Engineering An RC Helicopter Via Tinkercad

August 20, 2021 by Lewin Day 5 Comments

Radio control toys can be great fun to play with. However, at the bottom end of the market, sometimes you find you’ve bought something that just doesn’t work quite right. [saulemmetquinn] found that with a cheap RC helicopter, and set about re-engineering the design in Tinkercad.

The entire frame of the original helicopter was discarded, replaced with one made out of CAD-designed and 3D printed components. The end result is far lighter and less cumbersome than the original design, while also managing to look a lot more like an actual helicopter. It also served to correct some of the problems which [saulemmetquinn] stated made the original toy difficult to fly.

Assembling your own tiny helicopter motors and mechanisms would be quite difficult, and time consuming. [saulemmetquinn] was instead able to leverage the good parts of the original design, and build something better from that. It’s very much the essence of hacking, right there.

We’ve seen other toy helicopters hacked too, like the famous Syma S107G. If you’ve got your own tiny flying hacks, be sure to drop us a line.

A Cold Gas Thruster On An RC Car

August 15, 2021 by Lewin Day 12 Comments

Tesla have boldly claimed that one day they’ll ship a Roadster complete with a cold-gas thruster for truly ridiculous acceleration. Whether or not that ever comes to pass remains to be seen, but [Engineering After Hours] decided to try out the technology on an RC car instead.

The thruster uses a pair of disposable CO2 canisters to deliver 1770 g of thrust via a converging-diverging nozzle. Actuated by servos and a simple valve, the system dumps the high-pressure CO2 to help accelerate the car up to speed. Paired with sticky tires and a powerful brushless motor, the plan was to try and beat Tesla’s claimed 1.1 second 0-60mph acceleration figure for the thruster-boosted roadster.

Unfortunately, the high center of gravity of the RC car led to stability issues, largely due to the mounting of the thruster itself. Additionally, the high weight of the car – around 4.3kg – meant that at best, the thruster would only add 0.5g to the vehicle’s acceleration.

While the car didn’t net a quick 0-60 time, it’s still neat to see a cold gas thruster on an RC car. It may not have been a Tesla-beater like some earlier projects, but it was cool all the same. Video after the break.

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Solar Plane Is Like One Big Flying Solar Panel

May 29, 2021 by Lewin Day 15 Comments

Solar-powered plane concepts typically focus on high-efficiency glider-type designs, so as to make the best possible use of the limited power available from the sun. [rctestflight] wanted to try a different school of thought, instead building a relatively inefficient plane that nonetheless packed a huge amount of solar panels on board.

The plane consisted of a pizza-box style design, with a simple foam rectangular wing that was absolutely covered in solar panels. The plane was controlled with an off-the-shelf autopilot, and fitted with cheap, no-brand MPPT modules to handle charging the batteries. The plane faced difficulties in flight, most often with stability, which led to the autopilot getting the plane lost on one occasion. However, one flight was achieved with a full one hour and thirty minute duration, indicating the solar panels were helping to extend flight times beyond what was capable with batteries alone.

Further research on the ground showed that the cheap MPPT modules were wasting power, and there was more to be had. A better MPPT module was subbed in and showed that the panels could generate up to 5 amps under good conditions, while the plane only needed roughly 4.2 amps to fly. This would allow for indefinite flight in sunny conditions, though probably would not allow enough energy to be banked to fly 24 hours round the clock due to the lack of power at night.

We’ve followed [rctestflight]’s solar plane experiments for a while now, and can’t wait to see the next iteration. Video after the break.

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Modding A Hot Wheels Car Into A Radio Controlled Drift Weapon

April 23, 2021 by Lewin Day 14 Comments

Hot Wheels are some of the most popular diecast toy cars worldwide. The car bodies are faithful recreations of the real thing, though the models are mere stationary playthings. That wasn’t good enough for [Jakarta Diecast Project], who set about modifying a little BMW E30 M3 into an awesome radio-controlled drift car.

The build starts by disassembling the original car, and pulling out the original wheels. The baseplate is then modified to accept a new rear suspension and axle assembly. A small DC motor is mounted to the assembly to drive the rear wheels. A set of front steering knuckles are then installed up front, with their own suspension and hooked up to a tiny servo for steering. Everything’s controlled by a compact off-the-shelf RC receiver, which even features a gyro to help keep the tiny car straight under acceleration. The bodyshell is then stripped of paint, and given a sweet bodykit, before receiving a lurid orange paint job and decals. It’s reattached to the car’s baseplate via magnets, which make taking the car apart easy when service or modifications are required.

While the build doesn’t go into the nitty gritty on some of the harder parts, like the construction of the incredibly complex front knuckles, it’s nonetheless a great guide to building such a tiny and well-presented RC car. In looks and performance, the result trounces typical commercial offerings in the same scale, as you’d expect from such a hand-crafted masterpiece. It may not be the smallest RC car we’ve featured, but it is one of the coolest. Video after the break.

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Teardown: Linkimals Musical Moose

April 13, 2021 by Tom Nardi 23 Comments

Like so many consumer products these days, baby toys seem to get progressively more complex with each passing year. Despite the fact that the average toddler will more often than not be completely engrossed by a simple cardboard box, toy companies are apparently hell-bent on producing battery powered contraptions that need to be licensed with the FCC.

As a perfect example, we have Fisher-Price’s Linkimals. These friendly creatures can operate independently by singing songs and flashing their integrated RGB LEDs in response to button presses, but get a few of them in the room together, and their 2.4 GHz radios kick in to create an impromptu mesh network of fun.

They’ll soon be back, and in greater numbers.

Once connected to each other, the digital critters synchronize their LEDs and sing in unison. Will your two year old pay attention long enough to notice? I know mine certainly wouldn’t. But it does make for a compelling commercial, and when you’re selling kid’s toys, that’s really the most important thing.

On the suggestion of one of our beloved readers, I picked up a second-hand Linkimals Musical Moose to take a closer look at how this cuddly pal operates. Though in hindsight, I didn’t really need to; a quick browse on Amazon shows that despite their high-tech internals, these little fellows are surprisingly cheap. In fact, I’m somewhat embarrassed to admit that given its current retail price of just under $10 USD, I actually paid more for my used moose.

But you didn’t come here to read about my fiscal irresponsibility, you want to see an anthropomorphic woodland creature get dissected. So let’s pull this smug Moose apart and see what’s inside.

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Driving Upside Down With An RC Fan Car

February 3, 2021 by Lewin Day 8 Comments

We’ve all seen those tiny little RC cars that can climb walls thanks to the suction generated with fans. Their principle is essentially the opposite to that of a hovercraft. [Engineering After Hours] wanted to build his own RC car that could do the same, driving upside down and generating huge amounts of grip.

The build is based on a Traxxas RC car, but heavily modified for the task. An undertray is crafted, with ducts feeding a pair of twin 50mm electric fans. A skirt is fitted around the edge of the undertray, helping create a seal to maximise the downforce generated. This skirt is the area of much engineering effort, as it must form a good seal with the ground, particularly over minor pertubations, without creating undue levels of friction. Suspension components correspondingly need to be beefed up to stop the car bottoming out with the huge downforce generated by the fan system.

After much experimentation, the kinks are worked out, and the car is able to drive upside down successfully. It generates far more downforce than earlier wing experiments from [Engineering After Hours], as expected – with a tradeoff of higher weight and complexity. With the plan to create an RC car capable of huge lateral acceleration, we can’t wait to see what comes next. Video after the break.

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