Wing for iNav - cheap and cheerful start

IanSR

Active member
Well weather was good enough for a quick flight tonight just before dusk, so it's a Matek F405Wing flight controller inside a bashed up ARWing, I updated inav to v2, loaded up the default wing profile, threw in an Frsky XM+ and basically followed the recommendations from Matek as to GPS etc. UART location.

Pretty much everything was new, I'd never used an FRSky receiver, and obviously not the Matek, last time I tried to build an inav drone it destroyed itself in a tree when testing position hold hence the move to FRSky, I still have the FlySky receiver from the quad, but don't trust it, and all my LemonRX's are otherwise occupied.

Assigning all the switches on my Jumper remote was the most time consuming bit, I also didn't run any camera equipment inside or out (as recommended by Painless360 on YT for maiden flights), and had to swap the mixer assignment around, but other than that it was a breeze to setup, just take things slowly, and check three times, everything stock other than increasing the max angle in angle mode, I also manually adjusted the allerons to be perfectly aligned so as to avoid trimming on the remote (something you are not supposed to do with inav).

First launch and the thing nose dives into the ground, I'm like you piece of s**t, then looked at the remote and realised I'd knocked it into altitude hold mode while the wing was on the ground lol, second attempt it went straight up (didn't use autolaunch) and I went five mistakes high, trotted about s bit, then stuck it into trim learning mode, landed and did all the bits for that, checked it back up then proceeded to check stuff, altitude hold worked fine (as I already knew lol) and teenager mode (sorry nav position hold) worked too, although it scarred the crap out of me when it turned right and proceeded to fly towards the houses behind me, but it did turn in the end, I then briefly checked return to home and that seemed to work too, then the light was getting too dark so I called it a night.

I must admit it was pretty cool to just flick a switch and watch it do circles, that's gonna be seriously useful when people walk up to me and start asking questions (happens a lot) as I will actually be able to look at them, tomorrow I will check the failsafe, it's the only thing left, then add some camera equipment.

So don't worry too much, out the box this Matek F405 is simply awesome, I might get the F411 and throw it in the Long-EZ sometime in the future (still waiting to maiden that).
 
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CarolineTyler

Legendary member
I've totally lost my nerves with flying this iNav wing. the Stated flying weight is 290gms, the inav wing comes in at 350gms, so a little overweight.

SO..........

I've only gone and done this....
IMG_20181116_212711175.jpg IMG_20181116_212731083.jpg

Built another non-iNav wing that I care less if it crashes. This one comes in 300gms including the FPV equipment.
Hoping for maiden tomorrow!
 

kilroy07

Legendary member
So don't worry too much, out the box this Matek F405 is simply awesome,
Good to know! Now that I have got mine fixed and wired;
https://forum.flitetest.com/index.php?threads/desoldering-tips-tricks.56078/
(Now I have to figure out where I'm putting the second I ordered in case I bricked this one.)

My plan is to wire it to my Kraken next week (vacation week!)
That'll give me some time to get more familiar with inav and the options settings.
Gotta say I really love having the little OLED onboard for real-time info! Oh, and the On Screen Display is just too cool for FPV (I was always jelious of the rotor crowd because of that!)

This one comes in 300gms
So, (after the maiden) strap another 50 grams to it to see if the other one will fly! :LOL:
Good Luck!
 

CarolineTyler

Legendary member
Good to know! Now that I have got mine fixed and wired;
https://forum.flitetest.com/index.php?threads/desoldering-tips-tricks.56078/
(Now I have to figure out where I'm putting the second I ordered in case I bricked this one.)

My plan is to wire it to my Kraken next week (vacation week!)
That'll give me some time to get more familiar with inav and the options settings.
Gotta say I really love having the little OLED onboard for real-time info! Oh, and the On Screen Display is just too cool for FPV (I was always jelious of the rotor crowd because of that!)


So, (after the maiden) strap another 50 grams to it to see if the other one will fly! :LOL:
Good Luck!
That is exactly what I will be doing and carefully noting the needed reflex etc.
The little oled screen is totally un-necessary but I thought ... Why not ;)

I hope you will shout "Release the Kraken" as you launch!!!!
 
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IanSR

Active member
Good to know! Now that I have got mine fixed and wired;
https://forum.flitetest.com/index.php?threads/desoldering-tips-tricks.56078/
(Now I have to figure out where I'm putting the second I ordered in case I bricked this one.)

My plan is to wire it to my Kraken next week (vacation week!)
That'll give me some time to get more familiar with inav and the options settings.
Gotta say I really love having the little OLED onboard for real-time info! Oh, and the On Screen Display is just too cool for FPV (I was always jelious of the rotor crowd because of that!)


So, (after the maiden) strap another 50 grams to it to see if the other one will fly! :LOL:
Good Luck!

Make sure you remember to make the fixed wing adjustments for inav before flying, one of them is very important as it prevents the flight controller going into failsafe mode if you accidentally forget to disarm the plane after landing, which depending on your failsafe setting, can put the craft into return to home mode while its sitting on the grass, I almost lost my fingers and did loose a motor and ESC because of this, I can't remember exactly which setting it is just do all the recommendations for fixed wing that are in the release notes.

My Matek F450 is stuck high up in a tree at the moment, but the F411 equipped sister ship might fly tomorrow, I've got fedup with trying to fly smaller stuff like the Long-EZ, now I just stick to the ARWing. Gotta agree on the oled, I don't turn on my VTX until it's ready to fly so having the oled there is a big help.
 

kilroy07

Legendary member
The little oled screen is totally un-necessary but I thought ... Why not ;)
'Cause it's dead sexy, that's why!

When I saw your install, I ordered one right away (just a white one, not the fancy Yellow and Blue!) ;)
I'm really glad I did, it's pretty cool and it was ridiculously easy to setup in INAV.

I've got my light bar just showing Mode and GPS status, there's SO MUCH you can do in INAV... I think I spent and hour playing with the LEDs then figured "I'm not going to remember which light is which..." :LOL:

Make sure you remember to make the fixed wing adjustments for inav before flying,
I picked one of the default wing configurations, (I don't recall which at the moment) I just spent an hour or two getting everything running (the GPS communication speed had me thinking I had a dud module for awhile....
I'm going to spend a large part of next week studying all the options and hopefully get a maiden in before the end of the month... But that MIGHT wait as it's pretty darn chilly here in the Midwest this time of year!

Thanks to everyone for posting, I learn so much just reading and following your adventures!
(y)(y)
 

IanSR

Active member
It's

set failsafe_throttle_low_delay = 0

Type that into the cli and then type save and hit enter.

I genuinely think this should be the default setting, on my first few flights I was so excited that the thing flew that when it landed I forgot to disarm it, and about ten seconds after it landed the throttle went to 75% and I nearly lost my finger in the process, once I realised what this was and after having the replace the motor and ESC I did the same thing again but when it started this time I chucked it up into the air, it proceeded to climb to RTH altitude and circled above me with en route go home on the osd. Very nasty little bug if you don't know about it.

Also, if you're connected to the configuration software, inav won't arm you have to go to the motor tab and switch the little toggle switch to on before it'll arm - another safety feature, so if like me you've got it all connected up but it won't arm, that's the reason why lol.
 

kilroy07

Legendary member
set failsafe_throttle_low_delay = 0
I think i saw that under a reference to sailplanes... but now that I think about it... maybe it was the other way round where you wanted to set it different so your sailplane would not go into return to home mode... Have to look into it more, it may be set as default in the newer version.

Well... at least it tried to go home... so at least you had it programmed right!
(Kinda feel like I've jumped into the deep end of the pool at times...)

So, in INAV you change config variables by the command line?.... (That's WAY different than modifying the code in Marlin for 3D printers.)
But, I guess you aren't compiling code all the time... maybe that makes sense for the end user... Huh. :unsure:

Can't wait to dive into this more next week... although weather might be an issue for awhile now.
Just above freezing today... :oops:
 

IanSR

Active member
Yeah it's something like that, it's for if you do a lot of gliding with the throttle off and it stops the flight controller misunderstanding the throttle being in the off position as a failsafe. It's only stuff like this that you do via the command line interface (bottom left tab in iNav configurator) most of the stuff is done via the gui.

I've just seen a lot of people complaining about inav doing this (motor seemingly going to 100% throttle after landing) so I've made it my mini mission to get this info out there, last thing you need is to lean over the model to pick it up just as it bursts into life.
 

IanSR

Active member
Ok so I gotta question regarding inav after I finally got the 405 back out the tree and i guess this is the best place to ask since we all have it.

So before all this crap at Gatwick started, I stuck the F411 into a bloody wonder, everything seemed to work just fine, but as soon as I went anything over 30mph the thing with shake back and forth and up/down, I guess they're called ossifications, switch into manual/pass through mode and all these issues went, but as you know the bloody wonder is a bit of a bucking bronco so I like to fly it with a bit of help.

Previously it had a lemon rx stab+ in which all you did to dial out the oscillations was turn down the gain, the lemon also had three modes, full stab (I guess angle mode in inav), intermediate (horizon maybe?) and pass through.

So my question is how to do 'dial down the gain' on the stabilisations in inav for this, is there a simple 'gain' setting like in the remote? I used the preset mix for standard plane, and I tried both auto trim and auto tune but neither worked.

Any ideas where to start on the pids? I'm totally clueless when it comes to these (the ARWing works perfectly out the box on 800mm presets so I never had to check this over before).

Thanks and merry Xmas.
 

CarolineTyler

Legendary member
Ok so I gotta question regarding inav after I finally got the 405 back out the tree and i guess this is the best place to ask since we all have it.

So before all this crap at Gatwick started, I stuck the F411 into a bloody wonder, everything seemed to work just fine, but as soon as I went anything over 30mph the thing with shake back and forth and up/down, I guess they're called ossifications, switch into manual/pass through mode and all these issues went, but as you know the bloody wonder is a bit of a bucking bronco so I like to fly it with a bit of help.

Previously it had a lemon rx stab+ in which all you did to dial out the oscillations was turn down the gain, the lemon also had three modes, full stab (I guess angle mode in inav), intermediate (horizon maybe?) and pass through.

So my question is how to do 'dial down the gain' on the stabilisations in inav for this, is there a simple 'gain' setting like in the remote? I used the preset mix for standard plane, and I tried both auto trim and auto tune but neither worked.

Any ideas where to start on the pids? I'm totally clueless when it comes to these (the ARWing works perfectly out the box on 800mm presets so I never had to check this over before).

Thanks and merry Xmas.
In general P is the Power of the response, D is the dampening of that response.
Higher P = A quicker change of the control surface
Higher D = Reduces the oscillation around the required position
See the graphs at the end of this page for a visualisation of this...
 

makattack

Winter is coming
Moderator
Mentor

IanSR

Active member
Auto tune didn't do anything because I couldn't fly fast enough for it to do its job.

I did @makattack but it didn't make sense at the time, it probably will soon.
 

Mark Miner

New member
Been flying INAV for about a month. Some have mentioned it is a bit of a learning curve, with which I concur. Once set up though it just seems to work very very well. Autolaunch is stupendous. I am also very happy with autotrim and autotune. I put them both on the same three way switch. When flying, put it in autotrim mode, after about two seconds of you flying straight and level, it saves your new trims. If you like the way it is flying, just leave the autotrim switch on, land, disarm and the new trims are saved. If after you fly for a few seconds if the trims do not feel right, just switch it off, it reverts, and then flip it on again. As soon as you like the trims, just leave the switch in autotrim mode, land and disarm and they are saved! Then put your three way switch back to position that shuts off autotrim (after you land and disarm). Also if you do put them both on the same three switch, put off in the middle!!

Autotune is a bit more tricky. Fly to an altitude you like, switch on aututune, fly around for a couple of minutes the hardest you would expect to fly it. Afterwords while still in the air, turn off autotrim, then land. After disarm, use the stick command to save your newly tuned PIFF. Alternatively you can connect to computer while battery still connected, view the PIFF page and then hit save and reboot.

Stick command to save is shown in bottom right.

1546462651810.png



INAV flight including autolaunch.

And agreed regarding the Matek405 Wing Flight Controller. It was a joy to build and configure. The INAV flight is from my little quick scratch built wing and it added a whole new dimension to flying it.
 

IanSR

Active member
Agreed, both the f405 and F411 Wing are a joy to work with, seriously considering putting inav on my quad too as I have the F405CTR in that and betaflight is like drawing blood from s stone by comparison.

I've just managed to cram the F405 into a bloody wonder / super bee hybrid (bloody wonder airframe with super bee motor mounts and electronics), this will be an experience, never flown anything with differential thrust before lol.
 

Mark Miner

New member
Ok so I gotta question regarding inav after I finally got the 405 back out the tree and i guess this is the best place to ask since we all have it.

So before all this crap at Gatwick started, I stuck the F411 into a bloody wonder, everything seemed to work just fine, but as soon as I went anything over 30mph the thing with shake back and forth and up/down, I guess they're called ossifications, switch into manual/pass through mode and all these issues went, but as you know the bloody wonder is a bit of a bucking bronco so I like to fly it with a bit of help.

Previously it had a lemon rx stab+ in which all you did to dial out the oscillations was turn down the gain, the lemon also had three modes, full stab (I guess angle mode in inav), intermediate (horizon maybe?) and pass through.

So my question is how to do 'dial down the gain' on the stabilisations in inav for this, is there a simple 'gain' setting like in the remote? I used the preset mix for standard plane, and I tried both auto trim and auto tune but neither worked.

Any ideas where to start on the pids? I'm totally clueless when it comes to these (the ARWing works perfectly out the box on 800mm presets so I never had to check this over before).

Thanks and merry Xmas.


I would imagine that you no longer have the stabilizing RX in it? Having stabilizing RX and INAV at the same time would be bad JuJu.

I posted below the autotune instructions. I think this would be key. I note that you said you did not fly fast enough to accomplish. I would try it again. Get it high up, fly around, oscillations and all, then hit autotune. Fly around a bit more including whatever you usually do to cause the oscillations. If this fixes it, switch autotune off again, land then use the stick command to save the changes it just made. Or after disarm, but with battery still plugged in, look at the PID page, see that it made some changes then push save and reboot. Yet another alternative would be to fly it, note the oscillations, land, add 5 to the D-Term for roll and pitch, save it, fly it and keep adding 5 till it smooth. If you notice that the oscillations are only in pitch or only in roll then only change those settings. If adding 5 at a time to both, suddenly pitch is good but roll still oscillates then good. Pitch is set and just add 5 to roll until it is D-Dampened as well. D-Term (derivative of course, but dampening in practice)

I hope it works well for you, INAV really is fantastic and if put it on the Matek405 wing it is so easy it is practically cheating. (I am not affiliated with them in any way)

Mark Miner
 

ElectriSean

Eternal Student
Mentor
Agreed, both the f405 and F411 Wing are a joy to work with, seriously considering putting inav on my quad too as I have the F405CTR in that and betaflight is like drawing blood from s stone by comparison.

Unless you are running a camera drone and need GPS modes I'd recommend against iNav on a quad, there is really no comparison in how it flies. Also, auto-tune is a fixed wing only function right now. What problems are you having with Betaflight?
 

IanSR

Active member
Unless you are running a camera drone and need GPS modes I'd recommend against iNav on a quad, there is really no comparison in how it flies. Also, auto-tune is a fixed wing only function right now. What problems are you having with Betaflight?

Oh nothing specific, just in relation to the relative plug and play feature of inav, it's a bit more work, I'm lazy lol.
The only specific issue I'm having is my FC has a barometer and although everything is tuned on, there's still not an option in the modes menu for altitude hold.

@Mark Miner thanks for the hints, I'll give them a go next time I fly, was intending going today but I've come down with flu, typical first time I spend any meaningful time away from home over Xmas with other humans and I catch this.