What hardware do I need to start with ArduPilot?

ArduPlane
1

I’m a software enigneer and I want to do a deep dive into ArduPilot for fixed wing planes (ArduPlane). I’ve been reading the code and running some simulations. But of course, there’s nothing like the real thing. I’ve been flying FPV quadcopters for a couple years but I’ve never flown a fixed wing. So I’m now making a list for the hardware I need to start.

I was thinking of buying the following:

Some questions I have:

  • I also want to control the airplane with a GCS. What hardware do I need to remotely connect my laptop to the airplane?
  • What do you think of the items on this list? Do the items make sense?
  • Am I missing anything? All tips are welcome.
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The matek wing controllers are easy to use and very suitable for fixed wing and rover use.

1 Like
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Will a Pixhawk 6c even fit in that plane?
Get a Radiomaster Tx16S instead.

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Agree about the TX16S and recommend ExpressLRS as the protocol. There may be a slight amount of frustration in initial setup, but ExpressLRS performs quite well once configured. It’s certainly no more frustrating than the myriad of FrSky firmware nightmares you’d experience otherwise.

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Thanks for the tips @dkemxr and @Yuri_Rage. The TX16S indeed looks good. Especially because I think it can also receive telemetry (is that correct?). From what I understand I also need a telemetry module in the plane. Can I buy the SiK Telemetry Radio V3 module and connect it to the TX16S?

And then I can hook up the TX16S to my laptop to have my GCS talk to the plane right?

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You can use yaapu script if you dont need full gcs, all depends what you are doing with the vehicle,
Yaapu is designed to give autopilot telemetry back to transmitter and display it on treansmitter screen widget

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@Scott_Nunan - I do really want to use the GCS. Am I correct in that I need to install the SiK Telemetry Radio V3 module in the airplane, which I can connect to the TX16S, which in turn can be hooked up to the laptop?

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There are many ways, but a telemetry link will normally be flight controller to gcs pc, the rc link is fc through reciever to transmitter and mostly includes telemetry as well as rc control. But you can fly or control through telemetry link instead of rc link and you can also use something like yaapu on tx which negates the need for a laptop/tablet gcs for fc telemetry information.
Thereis also lte options which can do control, telemetry and video all in one link and is very simple hardare wise, but servers are needed etc
There is also some rc transmitter rf modules that can connect locally to gcs laptop and provide the telemetry link through the rc link so there is one link needed rather than two… examples are rfd and crsf modules

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The options in 2023 are pretty confusing really and id love to have some topology type diagrams that i could give as examples of common setup options in todays market

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Let’s clear up some confusion regarding telemetry and radios:

MAVLink telemetry is a bidirectional datalink for GCS communication, typically used via standalone radios, separate from the RC hardware. One resides on the vehicle, usually connected to a serial port. A paired radio is typically connected to the GCS computer via USB. SiK telemetry radios are often used for MAVLink this way.

RC telemetry is usually unidirectional, specific to the RC transmitter/receiver set and is often limited to a few key values like battery, RSSI, etc. Some RC protocols like SPort, FPort, ExpressLRS, and Crossfire support passthrough telemetry that carries a wealth of data, usually displayed on the RC transmitter screen through the use of a companion script called “Yaapu.”

There are a few projects like mLRS which do allow a full MAVLink connection between the RC transmitter handset and the autopilot, allowing for a USB connection of the RC transmitter to a GCS computer (as I think you’re alluding to in your question about telemetry radios), but they are fairly experimental, and thus likely temperamental. Additionally, I’m aware of some quite expensive RC options that also carry full bidirectional capabilities, but I think those may be beyond the scope here.

All that to say:
I recommend using a set of SiK radios to carry data to/from the GCS in addition to whatever RC hardware you choose.

I like the TX16S for its affordability, multi-protocol support, and large color screen that makes Yaapu telemetry extremely handy (as a companion to the GCS, not as a replacement).

My own use cases make it disadvantageous to maintain a constant, wired (or even Bluetooth) connection between the RC transmitter and GCS computer, so I will admit that I have not fully explored the bidirectional telemetry options and projects that afford such capability. I strongly prefer to have an in-hand, standalone remote, rather than having it tethered in some way. There is a modicum of redundancy in that, as well, since I can monitor most critical functions via passthrough telemetry on the RC transmitter screen in the case of GCS failure, and I maintain some measure of control and monitoring via the GCS computer in the case of RC hardware failure.

3 Likes
11

Wow, thanks for the comments @Scott_Nunan and @Yuri_Rage. They’ve been both confusing at first and enlightening at last.

I first thought that I would go with the route of passing all mavlink data through the radio, but as I see it now I rather go the way you (@Yuri_Rage) seem to suggest, having two separate data links; rc for manual control, and SiK telemetry radios for mavlink.

A few more questions which I hope you can answer:

  1. Since it’s a separate data stream I suppose the SiK radio on the ground needs to be plugged directly into the USB on the laptop, right?
  2. I suppose those SiK radios all work fine on Linux? Or do I need to watch for the ones which work on Linux and the ones which don’t?
  3. Since you link to another set of radio’s I presume you prefer that set above the one from Holybro which I linked to. Is that true, or are they both fine? I live in the EU/Netherlands so I need find a shop which ships from within the EU (to avoid extra shipping and importing costs). Is any decent set fine or are there specific brands which are good?
  4. I also need a receiver which works with the TX16S. I wasn’t aware there are multiple rc protocols. Which receiver do you suggest, and why? Are there specific ones which are good. I don’t need extremely long range or anything. Just any decent one will do for now.

All tips are welcome.

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  1. You can order the Tx16S with either a ELRS internal module or a Multi Protocol Module. ELRS is the latest spec and it has really no downsides other than some setup as Yuri mentioned. The MPM module supports a shitload of protocols.The most popular Receiver to pair with it is probably a Frsky unit. I have given up on Frsky for anything new but still have several models flying/driving. You can also plug in a Tx module in the back bay if you want. I do this with a Crossfire module. I would go with the ELRS system if I was buying a new radio.
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SiK “ground” radios have a USB connection for use with the GCS computer.

SiK radios all use (or should use) a common hardware architecture, so OS compatibility shouldn’t be of much concern. I prefer the mRo radios that I linked, but there’s nothing wrong with Holybro. Avoid the cheap clones from places like AliExpress (or Amazon, at times).

Like Dave, I’d go with an ExpressLRS TX16S and matching receiver. I like Matek’s receivers, but there are plenty of viable options.

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You guys are a lifesaver!

Ok, so finally, I decided to buy the Radiomaster RP1 ELRS Nano receiver. They’ve also got an RP2, RP3, EP1 and an EP2. I’m not sure what those are, but am I correct in my thinking that the RP1 will be fine?

Furthermore, I’ll buy the Holybro Sik Telemetrie Radio V3, of which they have a 433MHz and a 915MHz version. I tried reading around but I can’t find a definite answer. Does it matter at all which of these two I take?

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433mhz Europe, 915MHz USA. There are more frequencies legal to use, it all depends on your location.

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@HansHansHans - 433Mhz in Europe and 915MHz in USA. Is that for legal reasons?
I’m in the Netherlands, so 433 it is.

And do you know whether the RadioMaster RP1 ELRS Nano receiver I linked to above will work with the Radiomaster TX16S?

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Yes, for legal reasons. (868Mhz mag ook, zelf gebruik ik TeamBlackSheep Crossfire, zga hetzelfde als ELRS)

I’m not familiar with all types of Radiomaster TX16S versions and what they have as internal built-in frequencies. Apparently they are on version 4 now? I bought my TX16s approx two years ago and like it a lot. I use a TBS crossfire module in the module bay of my TX16s radio. To make the receiver work like you linked, you’ll need an ELRS module something like this: Happymodel Pro Micro ExpressLRS ELRS TX Module. I’m not familiar with the output power/wattage of that ELRS module and if you can change that in the settings. But i do know i choose TBS CRSF because i can transmit more than… uhm… the legal limit for those times you need more power.

When setting up a model in the radio, you’ll have to specify if you want to use the external RF-module (ELRS in your case) for control, or the Internal multi protocol module.

On this picture, the module bay is visible with the word radiomaster on it: https://droneshop.nl/pub/media/catalog/product/cache/57e05a978a5497b203ff83c2f6f349f4/r/a/radiomaster-tx16s-mk2-ag01-gimbals-back_2.jpg

I don’t know if you have any experience with droneshop.nl but to me they are reliable and ship fast.

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For sake of cost and complexity, @dkemxr and I are suggesting the TX16S radio that contains an internal ELRS module. No need to use the JR bay.

Nothing wrong with any of the receivers mentioned so far. They’ll all work just fine.

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Great, thanks! I’ll buy the radiomaster with the ELRS included indeed.

And then I think my final question. I want to hook up my radiomaster tx16s to my laptop so that I can fly in the SITL simulator. Can I simply hook it up with usb, or do I need some sort of dongle/converter for that?

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The TX16S can act as a USB joystick with no additional hardware.

EDIT: Bluetooth is only available via external modules.