Losing power gradually until copter lands

[stylesuxx]

Some users report that they are losing power gradually until they have to land. They can then re-arm and fly again for a limited time.

I have seen reports of this happening on 0.19. People also report that going back to 0.18 fixed the issue. When asked people said that they did set the power rating to 1S and disabled temp protection.

Hardware this has been happening on:

• Happymodel CrossF4 (S-H-50) - Quicksilver, not yet reproduced on BF
• Mobeetle 6
• Meteor 75 (At least this one, we can confirm that it's not a general problem - pinging @noctaro - I think you have this one and are not having any issues in that regard?)
• crazybeex V2 (S-H-50) - Quicksilver

If you are reading this and are running into the same issue, please speak up, comment your hardware and help us debug this issue.

[Noctaro]

Not sure if i changed bj version on the meteor75, will test it tomorrow on 0.19

[Noctaro]

No problems on my site. Working as expected. But keep in mind its the Meteor 75 2022. A-X-5 target. I am not sure if anything changed regarding ESC since the previous Metor 75 version. I think the old one came with BLHeli-S. Not sure if the old Meteor 75 has the same ESC as the old Meteor 65. I ll test the 65 too.

[stylesuxx]

Yeah, thanks for checking. Don't have any more information about the Meteor yet. Has not been happening on any of mine eiter, so who knows...

[cynfewl]

I think I am seeing this issue.

I recently replaced motors on my custom Meteor65 Pro build with a HappyModel Superbee F4 (S-H-50) which was running EX0802 19,000kv motors and is now running the new lighter HappyModel 0702 23,000kv motors (black bell). I updated Bluejay to 0.19.2 as part of the motor swap and am running Betaflight 4.4.0 with Bidirectional DShot.

For me it's more like a sudden loss of power which I initially thought might be a loose prop or motor bell, but after replacing props and checking the motors it was still happening. Definitely happening more at high throttle and disarming and taking off again the quad would fly ok for at least a couple of seconds before it happened again.

I tried changing motor timing from medium/high to high and increasing min/max startup, but neither fixed it. Power rating was set to 1S and temperature protection set to the default at 140C. I have just flashed back to 0.18.1 and this seems to have resolved the problem.

[damosvil]

@cynfewl could you please try again disabling temperature protection? You can also check temperatures by enabling EDT in cli:

set dshot_edt=on
save

Then add esc temperature osd element at the beginning of a screen line in Betaflight osd tab. You can also add max esc temp to flight summary

[cynfewl]

Apologies for the delay, but I think temperature protection is indeed the culprit.

I upgraded to 0.19.2 again, but this time disabled temperature protection. Enabling EDT and adding this to the OSD I can see that the ESCs start at about 230 degrees and one ESC (number 3) seems to max out and roll past 255. The quad flies fine with the temperature protection disabled and I don't see any loss of power.

I managed to recover the DVR file and have included the ESC temps at various points below.

Disarmed

Initial Arm

ESC Rolling Past 255

MAX ESC Temp 255

[damosvil]

Probable what is happening is that your aio battery rating is 1-2s so you need to configure esc power rating to 2s+ in esc-configurator.com tool.

Ps. I have checked and efectively uz65 aio is 1-2s capable.

[stylesuxx]

Thank you @cynfewl for coming back to us and confirming our suspicions.

Please just confirm that the temp read-outs are correct with the 2S+ power setting. Going forward we will disable temp protection by default and improve the tool-tip in regards to power rating.

[cynfewl]

This board is actually a Superbee F4 https://www.happymodel.cn/index.php/2022/07/28/superbee-f4-lite-aio-flight-controller-elrs-frsky-version-for-1s-tiny-whoop-drone/ which I believe is 1S only, but I will try it with the 2S setting as well and report back. Apologies if the craft name is a bit misleading.

Regardless I agree a call out in the tool-tip would be handy because I read that section as the cell count you intended to use on the board, not what the board was capable of running, so I would have got this wrong on my CrazybeeX quads that I am running on 1S.

[stylesuxx]

Ah, this is good to know. I think I have this same flight controller somewhere - I will try to reproduce it.

Yes, the power rating thing is not well explained right now and the truth is, that on a 1S rated board it could very well be 2S+ if they use a step up converter and the MCU's are not directly powered from battery voltage, which is the case most of the time on 1S boards. I think it's a bit difficult to tell users: "Check if your MCU is powered via a regulation circuit", but definitely more context is needed here.

If you could just confirm the behavior on 2S you would save me some time.

[cynfewl]

I can confirm that setting ESC Power Rating to 2S+ gives me ESC temperatures in the correct range of about 30 degrees. If I run into this issue on other boards I will perform similar tests and add comments here so we can keep track of affected hardware.

I wish I could easily identify how the MCU on these boards is powered, but neither my eyesight nor my electronics knowledge is up to that task I'm afraid.

Thank you very much @damosvil and @stylesuxx for your help and contributions to this excellent project.

[stylesuxx]

Well, I think the best place to add this information is to the Tested Hardware Wiki page.

What's really worth a lot is to know that this is indeed a real issue and we have a solution for it, so thanks again for helping us out here.

As background info: Temp protection has never been working properly and has been basically fixed in 0.19. We kept the default to be on, which in hindsight was a mistake, since by it being broken for ever, it technically always was off by default - simply never working and nobody noticed...

[stylesuxx]

Added explanation on how to fix in the wiki: https://github.com/bird-sanctuary/bluejay/wiki/FAQ#why-is-my-quadcopter-gradually-losing-power-until-it-lands

Future versions of Bluejay will have temperature protection disabled.