LockDownRadioControl

[MMESSITER]

Hello!

I’m new here - so I wonder if anyone is interested:

During lockdown, I began to learn about Arduinos and microelectronics. I was a musician really (oboe).

To cut a very long story very short, I’ve
since developed a full featured proportional radio
control system.

The circuits and PCBs are my design.
I had the PCBs made in China. I assembled them
at home. The cases I also
designed and 3D printed at home in PETG.
The comms protocol is my work.

The code is all C++ and is open source on
GitHub as my repo: “LockDownRadioControl”.

The system is based on Teensy 4.1 and Teensy 4.0 MCUs
and uses EByte ML01DP5 transceivers.

The system has these features, so far :

16 channels
4 flight modes
32 mixes
99 model memories
2.5 km range
FHSS (2.4 GHz, about 16 hops per second)
SBUS
Buddy boxing
Data compression
12 BIT servo resolution.
Colour touch screen GUI (Nextion 5” Intelligent)
Failsafe
Binding
5 point curves - straight, smooth, or exponential.
Telemetry for volts, gps, etc.
Diversity (two transceivers on RX)
Model memory sharing over RF (no wire or sd needed)
Local model memory backup system (sd card)
Audio feedback
Input remapping
User selectable screen colours and audio.
Real time clock (corrected by gps link)
Waveband scanning function.

Future plans include PID stabilisation using MPU6950.

This system seems worth sharing to me!
It’s not commercial - just for fun!

Malcolm MESSITER

[Lupo63]

It is simply fantastic what you have achieved starting from the experience as a musician !!! Some time ago I too made my very "basic" version (no expo, no rates, nothing like in the 70 years) using the casing of an old Futaba M6, an encoder copied from RCM & E and modified with the help of this forum. I did a remote ground test which seemed satisfactory but I never did flight tests. I would very much like to study in detail what you have accomplished.

Are you willing to share files, wiring diagrams and arduino codes?

Anyway, congratulations again.
Nino

[MMESSITER]

Hello Nino

Thanks! Yes of course I’m happy to share everything and I hope might learn something from others with greater experience than I in this area.

All is posted at:
https://github.com/Mmessiter/LockDownRadioControl

These files include all source code, .stl files and Gerber files for the PCBs. I try to keep these up to date but development is quite fast so sometimes confusion might result.
For example - I just upgraded from “enhanced” to “intelligent” Nextion displays. I am trying to keep the system backward compatible for those who wanted not to change hardware. It only means audio won’t happen. Also in the “sensor” hub code I discovered that while Teensy 3.2 works fine, the 3.6 and LC models do not work - so these code versions I better remove. I think that’s a small hardware bug.
Speaking of hardware bugs, I found one in the nRF24L01+ (which is the chip at the heart of the ML01DP5). And I found a work-around: This transceiver has two FIFO buffers, one in and one out, with space for three data packets in each. On the datasheet it says: “do not allow a fifo buffer to remain full for over 4 ms”. But it does not warn of the consequences!! The result, as I found, is that the chip stops working utterly until it’s rebooted. Not great when in the air. The fix is simply to flush the buffers after every send or receive. Essentially don’t use the buffer at all!

If you’d like to see an early test flight (a year ago) there’s one on YouTube at https://youtu.be/xAlO0PTQo08

Malcolm

[Lupo63]

Many Thanks Malcom,

I will tray to download and study what you have realized.
Really impressive !

Happy Easter

Nino

[MMESSITER]

I’m so glad you think so!

If you want to build one I can offer tech support!

[Martin]

Very impressive Malcolm. You've clearly put in a great deal of work. Welcome to the forum, by the way!

How readable is that GUI (Nextion 5” Intelligent) display in sunlight? I've yet to see a colour display that's really clear in bright conditions. I've got a RadioMaster TX16S, and its display looks fantastic on dull days or indoors; but on sunny days the non-backlit monochrome display on my old Taranis is much more usable - besides being much more economical on the transmitter's battery.

I'll take a look at your code and construction details, but I'm afraid I'm unlikely to build one right now - I already have too many proportional transmitters.

[Tobe]

Welcome to the forum and sure hope you will enjoy the forum and find interesting projects.
Sure impressive with all those features. I'm sure you had a good learning experience.

Cheers

Tobe

You might have noticed that I resized you picture, hope you didn't mind

[Pchristy]

I've known Malcolm for a number of years, and when he contacted me recently, with details of his project, I immediately suggested he post it here!

Back around 2006 (?), if memory serves, the UK hosted the European Helicopter Championships. It was Malcolm that found the ideal location for it, which was very well received by not only the organisers, but also the competitors.

He sent me a video of his first test flight with his system I'm sure he won't mind me sharing it here:



I thought he was extremely brave, testing an unproven system in a very aerobatic helicopter, but the evidence shows that he had no reason to worry!

Well done, Malcolm! And welcome to the forum!

I'm sure your system will generate a flurry of interest here - and with good reason!

--
Pete

[MMESSITER]

Gosh thanks!!
I realise that one main reason I became obsessed with the radio development was because every aspect is home grown - in *my* home!

Consequently I fully understand if others are a bit less enthusiastic about building one - designed by a complete stranger.

But how about someone else designing and building a new radio from scratch? Lots of people do that with models, but I’ve not seen any do a radio yet - not fully anyway. If I can - a mere oboe player - I think anyone can. And these days the needed information is all there on Google, and needed components are all pretty cheap on Amazon and EBay! Transmitters almost never crash either !!

The Nextion screen is extremely good (especially their latest) but as you suspect, in bright sun it’s quite hard to read, like many. So I suggest setup in the shade, then fly in the sun. In any case the screen will turn off after a (user definable) period, to save battery while you fly!

Malcolm

[Tobe]

If you brows around the forum you will find much more than you would expect!



...from bending the aluminum case, designing sticks, pc-boards to the servo design, a full 6 channel R/C set.