What "mode" is activated when landing, and uneven surface detected?

allen_993 · Apr 25, 2020

So the other day I was landing on a soft (ish) surface, and when I landed on the ground (I was in MANUAL), I held left stick full down and waited for engine shut-off. After a few seconds engines revved up and Solo started upward...I didn't pull stick up, but it headed up anyway. I had no very little upward clearance, I kinda panicked, hit a few small limbs, and Solo had a "soft crash". My question is: In that scenario, does Solo go in to HOME mode, FLY mode, or stay in MANUAL?

just_bruce · Apr 25, 2020

Sounds like you were landing under a tree. And that GPS might have been spotty at best.

I think solo switched over to FLY mode because the landing detector didn't tell it that is was on the ground and it suddenly had GPS. The landing detection received an update in I believe the 1.5.3 firmware to address problems with this.

allen_993 · Apr 26, 2020

I was indeed landing under trees, so I agree GPS could have been spotty. That is why I had Solo in MANUAL mode for the landing...in fact I generally always land in MANUAL. So are you saying that when Solo failed to detect that it was the ground (because ground was unlevel), and the stick continued to be full down...Solo automatically switched over to FLY mode??

BTW...I am running Open Solo v3.0.0.

timgilley · Apr 26, 2020

I don't have an explanation for why your Solo took off. I've had a few quirky landings including flips over the years. Generally when the surface wasn't level or the Solo needed calibration. You might try Boat Mode for manual landings under unusual conditions. As a rule I avoid flying near trees, structures and tight spaces. I've armed and launched near a tall tree. The problem is on RTL the drone wants to descend thru the tree canopy. Oops...abort landing.

allen_993 · Apr 26, 2020

timgilley said:
The problem is on RTL the drone wants to descend thru the tree canopy. Oops...abort landing.

I guess we've all had those "quirky landings"

And you are absolutely right about the RTL. I often have to launch from a less than optimal sites where trees are around, so when Solo looses signal and RTL is activated, I watch helplessly as it eventually starts heading straight down towards the tree tops, hoping like hell it regains signal REALLY soon!! I've never actually had it NOT regain signal before it hits anything, but it's very unnerving. Getting signal from directly underneath Solo can be tricky.

just_bruce · Apr 26, 2020

allen_993 said:
I guess we've all had those "quirky landings"
And you are absolutely right about the RTL. I often have to launch from a less than optimal sites where trees are around, so when Solo looses signal and RTL is activated, I watch helplessly as it eventually starts heading straight down towards the tree tops, hoping like hell it regains signal REALLY soon!! I've never actually had it NOT regain signal before it hits anything, but it's very unnerving. Getting signal from directly underneath Solo can be tricky.

Tilt your controller so the antennas point skyward. There is a thread on this site which shows the effective radiation patterns of the stock, Alfa, and FPVLR. You are in a 'donut hole' when Solo is directly overhead [or below] with the stock antennas.

Also, you may have lost signal briefly to the bird while landing, which might have caused it to switch to FLY or LAND modes. Hard to say without a log file.

Pedals2Paddles · Apr 27, 2020

Good money says it switched to RTL due to low battery, or due to losing signal with the controller depending on your conditions. A smaller possibility is ground effect and vibration leading to false baro readings making it think it was falling and throttling up to compensate. This usually causes a little hop up, not a steady climb. So most likely just switched to return home.

allen_993 · Apr 27, 2020

Pedals2Paddles said:
A smaller possibility is ground effect and vibration leading to false baro readings making it think it was falling and throttling up to compensate. This usually causes a little hop up, not a steady climb.

I actually think this is what happened. Before I entered in to the "tree covered" area for landing...I actually waited until the battery hit 25%, Solo initiated RTL, I took it out of RTL, I put it in MANUAL and proceeded to attempt landing. When Solo made contact with the unlevel ground, it got a bit tilted, the "little hop" you described occurred...and in my panic...I am pretty sure I mistakenly hit either the FLY or HOME button. I STILL haven't learned not to panic when things go "sideways"...gotta work on that. Thanks for the responses.

timgilley · Apr 28, 2020

If you're in the open and a landing gets strange then full throttle to 6-10 feet sets you up for a 'graceful' recovery.

allen_993 · Apr 29, 2020

If you're in an open area, it's a piece of cake...unfortunately, I was in an area under trees. Had landed there many other times, but this time, Solo just got a bit unlevel, and that caused a problem.