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Archive for the ‘RC transmitter’ Category

DSM (digital spectrum modulation) is a relatively new radio control technology that is ideal for long-range applications. It uses two methods, FHSS (frequency hopping spread spectrum) and DSSS (direct sequence spread spectrum), to transmit data, with the latter being especially resilient to interference and therefore suitable for transmission over long distances. If you want to take advantage of DSM for your robotics projects, James Bruton designed an open source transmitter that you can builds.

Bruton makes a lot of remotely operated robots, so he had a strong need for a good remote. His previous designs, while full of great features, didn’t have the kind of range that he wanted. So he created this new remote that incorporates DSM transmission technology. It contains two DSM transmitters to harness 20 individual channels. It uses those channels for four joysticks (each with three axes), four toggle switches, and four momentary push buttons. Together, those are enough to control even the most complicated robots.

Inside the remote’s 3D-printed enclosure is an Arduino Mega 2560 board. It monitors the various controls and outputs the data to a pair of OrangeRX 2.4GHz DSMX transmitters. It also outputs the battery voltage to a small three-digit, seven-segment display. Power comes from four 18650 lithium battery cells. This remote will work with any compatible DSM receiver, which are affordable and easy to integrate into a project, as they operate like a standard RC receiver.

The post An awesome new open source long-range RC transmitter appeared first on Arduino Blog.

Obviously, the most iconic piece of fictional hardware from the Back to the Future films is Doc Brown’s DeLorean DMC-12 time machine. But we’d have to agree with [Jason Altice] of CodeMakesItGo that the second-most memorable gadget is the modified Futaba remote control used to control the DeLorean from a distance. Now, thanks to his detailed build guide, you can build your own version of the time machine’s controller — complete with working speed readout.

Now to be clear, [Jason] isn’t claiming that his build is particularly screen accurate. It turns out that the actual transmitter used for the prop in the film, the Futaba PCM FP-T8SGA-P, has become difficult to find and expensive. But he argues that to the casual observer, most vintage Futaba transmitters are a close enough match visually. The more important part is recreating the extra gear Doc Brown bolted onto his version.

All but four of the display wires are fake.

To that end, [Jason] was able to source some screen accurate hardware to kit out his transmitter, such as the Unibox 140 project box and the metal 9 V battery clips. Other components, like the lighted Molex 1820 switch, were harder to track down. Luckily we live in the age of cheap desktop 3D printers, and he was able to run off an impressively accurate replica without too much trouble.

Of course, the stand out feature is the seven-segment LED speed indicator. Each digit is a separate 25 mm (1 inch) SC10-21SRWA display, which have been mounted together on a custom PCB along with a TM1650 controller. An Arduino Uno inside the Unibox 140 drives the display, and receives speed data from the transmitter in the car using a long-range Reyax LoRa RYLR998 module.

[Jason] built the GPS-equipped “speed box” to closely resemble the movie version, albeit with three functional digits compared to only two in the original prop. Internally it’s using the same LED display, LoRa module, and Arduino Uno as the transmitter. We liked the approach of keeping the hardware more or less the same on both sides of the link, keeps things nice and simple.

Now you certainly don’t need a DeLorean time machine to test out your finished remote control, but we appreciate that [Jason] went through the trouble of renting one so he could show off his creation in style. The final product looks great, and ranks right up there with the replica time circuits on the list of BttF props we’d love to have up on the shelf.

It’s wasn’t so long ago that RC transmitters, at least ones worth owning, were expensive pieces of gear. Even more recently than that, the idea of an RC transmitter running an open source firmware would have been considered a pipe dream. Yet today buying cheap imported transmitters and flashing a community developed firmware (if it didn’t come with it pre-installed to begin with) is common place. It’s not much of a stretch to say we’re currently in the “Golden Age” of hobby RC transmitters.

But what if even cheap hardware running customizable software isn’t enough? What if you want to take it to the next level? In that case, [Electronoobs] has an Arduino powered RC transmitter with your name on it. But this is no scrap of protoboard with a couple of cheap joysticks on it, though he has made one of those too. The goal of this build was for it to look and perform as professional as possible while remaining within the hobbyist’s capabilities. The final product probably won’t be winning any design awards, but it’s still an impressive demonstration of what the individual hacker and maker can pull off today with the incredible technology we have access to.

So what goes into this homebrew radio control system? Inside the back panel [Electronoobs] mounted the batteries, charging module, and the voltage regulator which steps the battery voltage down to the 3.3 V required to drive the rest of the transmitter’s electronics. On the flip side there’s an Arduino Nano, an NRF24 module, and an OLED display. Finally we have an assortment of switches, buttons, potentiometers, and two very nice looking JH-D202X-R2 joysticks for user input.

As you might have guessed, building your own transmitter means building your own receiver as well. Unfortunately you won’t be able to bind your existing RC vehicles to this radio, but since the receiver side is no more complicated than another Arduino Nano and NRF24 module, it shouldn’t be hard to adapt them if you were so inclined.

Low-cost consumer RC transmitters can be something of a mixed bag. There are some surprisingly decent options out there, but it’s not a huge surprise that hackers are interested in just spinning up their own versions either.



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