Terrible RC Transmitter Made Less Terrible

March 27, 2018 by Tom Nardi 32 Comments

It should probably go without saying that we’ve got nothing against the occasional bout of elaborate troubleshooting and repair, in fact it’s one of the most common things we cover here. As it turns out, people aren’t overly fond of being fleeced, and there are a lot of smart people out there who will put a lot of work in to keep from having to toss a favorite piece of gear into the trash. We can’t fault them for that.

But we have to say, we generally don’t see those kind of elaborate repairs for something brand new. Unfortunately, that’s exactly what [Marek Baczynski] had to do when trying to review the new iRangeX transmitter for his YouTube channel “dronelab”. He found a transmitter that was so poorly designed and constructed that he had to address a laundry list of issues to make the thing halfway tolerable. As you might expect, he’s not suggesting anyone go run and pick this one up.

The biggest problem is a fundamental flaw with how the gimbals are constructed. Due to poorly mated surfaces between the potentiometer and the stick itself, the accuracy of the controller is very low. The potentiometers don’t even return to zero when the sticks are released. Some tape was used to tighten up the connection and make the controller usable, but such poor tolerances are hard to forgive when accurate control is essentially the whole point of the device.

The other issues took a bit more debugging to figure out. The TX made an absolutely terrible screeching sound when turned on, but [Marek] was sure he was hearing a little bit of melody under the din. Putting the signal through the oscilloscope, he was able to confirm his suspicions. As it turns out, the buzzer used in the TX has a built in tone generator that was overriding the intended melody. Switching it out for a basic buzzer fixed the issue. Similarly, an issue where the radio wouldn’t turn on if it was recently turned off was tracked back to a resistor of the wrong value. Putting a ~~higher~~ lower value resistor in its place sorted that out as well.

It’s hard to imagine how this device made it out of the factory with so many wrong or unsuitable components, but here we are. Not that this would be acceptable at any price point, but as [Marek] points out in the video, it isn’t as if this radio is even all that cheap. For nearly $90 USD, it doesn’t seem unreasonable to expect something that actually works.

This isn’t the first time he’s put “cheap” RC hardware through the wringer. We recently covered his efforts to quantify latency in different transmitters. As the RC transmitter world gets increasingly competitive, detailed analysis like these help separate the real gear from the toys.

Continue reading “Terrible RC Transmitter Made Less Terrible” →

Geoffrey The Giraffe’s Last Call Of Toys For Hacking

March 22, 2018 by Roger Cheng 30 Comments

Many of us in the United States frequently browse the shelves of Toys R Us for things to hack on. Sadly that era will soon end with the chain’s closing. In the meantime, the entire store becomes the clearance shelf as they start liquidating inventory. Depending on store, the process may begin as soon as Thursday, March 22. (Warning: video ads on page.)

While not as close to hacker hearts as the dearly departed Radio Shack or Maplin, Toys R Us has provided the hacker community with a rich source of toys we’ve repurposed for our imagination. These toys served various duties including chassis, enclosure, or parts donor. They all had low prices made possible by the high volume, mass market economics that Toys R Us helped build. Sadly it was not able to keep its head above water in the low margin cutthroat competition of retail sales in America.

As resourceful consumers, we will find other project inspirations. Many projects on this site have sourced parts from Amazon. In commercial retail, Target has started popping up in increasing frequency. And no matter where new toys are sold, wait a few years and some fraction will end up at our local thrift store.

We’ll always have some nostalgia for Geoffrey the Giraffe, but toy hacking must go on.

Building A Tricorder Prop Worthy Of Mr Spock

March 19, 2018 by Tom Nardi 24 Comments

We’ve all been there. You want to assemble a proper Star Trek: The Original Series landing party prop set, but the TOS tricorders you can find on the market are little more than overpriced toys. Imagine the embarrassment of beaming down to Cestus III with a plastic tricorder. The Metrons wouldn’t have even bothered with the trial by combat with such a sorry showing.

Unhappy with the state of Star Trek props, [Dean O] decided to take matters into his own hands. He purchased a TOS tricorder from Diamond Select Toys and set out to modify it into something a bit closer to Starfleet standards. Anything painted metallic silver on the toy was replaced with a machined aluminum duplicate, adding some much needed heft. He even spruced up the controls and display.

To start, [Dean] stripped the tricorder down, separating all of the silver plastic parts and finding aluminum stock that was close enough to the desired dimensions. This ended up being .125″ plate for the sides, and .500″ bars for the horizontal dividers. To make the side panels he placed the original plastic parts over the aluminum, marked the mounting holes with a punch, and used the belt sander to shape them.

[Dean] then put in a more screen accurate Moire disc, and went as far as to get real watch crowns for the buttons (just like the prop used in the show). In a particularly bold move, he even drilled out the center of watch crowns to install plastic light pipes for LED illumination.

Last year we saw a build that crammed a Raspberry Pi into the same Diamond Select tricorder toy to excellent effect. Now somebody just needs to combine both projects and they’ll have the slickest tricorder in the Alpha Quadrant.

Traction Control Gets More Power To The Road For Tot-Sized Lamborghini

March 18, 2018 by Dan Maloney 21 Comments

We’ve all heard the complaints from oldsters: “Cars used to be so simple that all you needed to fix them was a couple of wrenches and a rag. Now, you need a computer science degree to even pop the hood!” It’s true to some extent, but such complexity is the cost of progress in the name of safety and efficiency. And now it seems this complexity is coming way down-market, with this traction control system for a Power Wheels Lamborghini.

While not exactly an entry-level model from the Power Wheels line of toddler transportation, the pint-sized Lamborghini Aventador [Jason] bought for his son had a few issues. Straight from the factory, its 6-volt drivetrain was a little anemic, with little of the neck-snapping acceleration characteristic of an electric drive. [Jason] opted to replace the existing 6-volt drive with a 12-volt motor and battery while keeping the original 6-volt controller in place. The resulting rat’s nest of relays was unsightly but sufficient to see a four-fold increase in top speed.

With all that raw power sent to only one wheel, though, the Lambo was prone to spinouts. [Jason] countered this with a traction control system using optical encoders on each of the rear wheels. A NodeMCU senses speed differences between the wheels and controls the motor through an H-bridge to limit slipping. As a bonus, a smartphone app can connect to the Node for in-flight telemetry. Check out the build and the car being put through its paces by the young [Mr. Steal Your Girl] in the video below.

The Power Wheels platform is infinitely hackable – from repairs to restorations to enhancements of questionable sanity, it seems like there’s nothing you can’t do with these little electric vehicles.

Continue reading “Traction Control Gets More Power To The Road For Tot-Sized Lamborghini” →

RC Car Hacked Into Paintball Shooting Tank

March 14, 2018 by Steven Dufresne 17 Comments

What’s more fun, driving RC cars around on rugged terrain, or having a paintball battle? How about doing both at the same time by making an RC controlled, paintball firing tank? [Nate] from the King of Random YouTube channel did just that by mounting a modified paintball gun to a stripped-down RC car, adding an RC trigger to remotely fire the gun, and covering it all in EVA foam armor in the shape of a tank. And then he did it again so that he’d have someone to battle against.

He walks through the full build in the first video below, but here are some things that stood out for us. It took some fiddling to get a servo to pull the gun trigger but how could he remotely control the servo? For that, he took over the car’s RC receiver signal for controlling audio and made it turn on and off the servo instead. We also like his use of aluminum bar. This stuff is available in the hardware section at stores like Home Depot and is easy to cut and bend. You can see it used here for mounting Wimshurst machine parts to a bicycle, and in this hack, [Nate] used it to mount the paintball gun rigidly to the car frame. He did surprise us when he used rivets instead of nuts and bolts to hold the frame together. That’s not something you see often, and it worked great.

As we said, he made two of them. In the second video below, watch the tanks in action as [Nate] and fellow YouTuber [Stuart Edge] have a tank battle in the desert.

Continue reading “RC Car Hacked Into Paintball Shooting Tank” →

Zip Tie Quadcopter Frame Is As Cheap As They Come

March 9, 2018 by Tom Nardi 27 Comments

We’ve seen some cheap quadcopter builds over the years, but this one takes the cake. After seeing somebody post a joke about building a quadcopter frame out of zip ties and hot glue, [IronMew] decided to try it for real. The final result is a micro quadcopter that actually flies half-way decently and seems to be fairly resistant to crash damage thanks to the flexible structure.

The first attempts at building the frame failed, as the zip ties (unsurprisingly) were too flexible and couldn’t support the weight of the motors. Eventually, [IronMew] realized that trying to replicate the traditional quadcopter frame design just wasn’t going to work. Rather than a body with arms radiating out to hold the motors, the layout he eventually came up with is essentially the reverse of a normal quadcopter frame.

Zip ties reinforced with a healthy coating of hot glue are arranged into a square, with a motor at each corner. Then four zip ties are used to support the central “pod” which holds the battery and electronics. No attempt is made to strengthen this part of the frame, and as such the heavy central pod hangs down a bit in flight. [IronMew] theorizes that this might actually be beneficial in the end, as he believes it could have a stabilizing effect when it comes time to record FPV video.

He mentions that he’s still struggling to get the PID values setup properly in the flight computer, but in the video after the break you can see that it’s flying fairly well for a first attempt. We wouldn’t recommend you tear into a bag of zip ties when it comes time to build your first quadcopter, but it does go to show that there’s plenty of room for experimentation.

We’ve covered a number of unique quadcopter frames if you’re looking for something to set your next build apart from the rest. If you’ve got a big enough bed you can 3D print a very nice frame, but if you’ve got more time than equipment, you could always cut one out of a piece of plywood.

Continue reading “Zip Tie Quadcopter Frame Is As Cheap As They Come” →

Single Motor, Single Piece 3D Printed Hovercraft

March 8, 2018 by Steven Dufresne 12 Comments

RC hovercrafts offer all sorts of design options which make them interesting projects to explore. There are dual-motor ones where one motor provides lift while the other does the thrust. For steering, the thrust motor can swivel or you can place a rudder behind it. And there are single-motor ones where one motor does all the work. In that case, the airflow from the motor blades has to be redirected to under the hovercraft somehow, while also being vectored out the back and steered.

[Tom Stanton] decided to make a single-motor hovercraft using only a single 3D printed piece for the main structure. His goals were to keep it as simple as possible, lightweight, and inexpensive. Some of the air from the blades is directed via ducting printed into the structure to the underside while the remainder flows backward past a steering rudder. He even managed to share a bolt between the rudder’s servo and the motor mount. Another goal was to need no support structure for the printing, though he did get some stringing which he cleaned up easily by blasting them with a heat gun.

From initial testing, he found that it didn’t steer well. He suspected the rudder wasn’t redirecting the air to enough of a sideways angle. The solution he came up with was pretty ingenious, switching to a wedge-shaped rudder. In the video below he gives a the side-by-side comparison of the two rudders which shows a huge difference in the angle at which the air should be redirected, and further testing proved that it now steered great.

Another issue he attacks in the video below was a tendency for the hovercraft to dip to one side. He solves this with some iterative changes to the skirt, but we’ll leave it to you to watch the video for the details. The ease of assembly and the figure-eight drift course he demonstrates at the end shows that he succeeded wonderfully with his design goals.

Continue reading “Single Motor, Single Piece 3D Printed Hovercraft” →