Mikrokopter firmware update .84
- Thread starter RTRyder
- Start date
The MK was in completely manual flight mode at the time I had not switched in P/H or A/H though I was about to when it went off on its own, here's what the log shows...
At 37 seconds into the flight the elevation reading dropped to zero and stayed there for the remainder of the flight, approximately 41 seconds before the Mk headed for the ground at 78 seconds of flight time. At 73 seconds the compass, which had been relatively steady to that point jumps from a reading of 13 degrees to 355 degrees, stays there for one more second, then drops back to 8 degrees as the MK is now in flyaway mode since the compass jump to 355 degrees. At the same time the roll angle changes from 5 degrees to 116 degrees which is basically impossible as the Mk should be heading for the ground at that angle but it was flying level although quickly to the left. It traveled at a groundspeed of 4 meters/second for another second when the roll angle reverted back to a more normal reading of 12 degrees and then in the next second shows a roll angle of 48 degrees which is consistant with the flip I saw it do as it headed down and the remainder of the data is the Mk falling to the ground.
Based on what I see in the log the only conclusion I can draw is software glitch, the F/C was not seeing the correct readings from the altitude sensor, the compass, and the accelerometer at the point where it went into flyaway mode and shortly afterward it regained some state of normality followed by more confusion causing it to flip it into the ground which IMO was not necessarily a bad thing at that moment. A continuation of flyaway would likely have had more dire consequences up to the possibility of losing it entirely had it gained some altitude. The direction it was headed in would have put it over a heavily wooded swampy area where recovery would have been extremely unlikely if in fact it could have been found at all.
I've reverted back to .82 firmware and as soon as the weather clears up I'm going to take it over to the big flying field and give it another try with a mostly discharged battery so even if it does go walkabout again it won't get very far. If it behaves on that flight I'll give it a go with a fully charged set of batteries and see what happens.
Ken
Ken there was a post made at the 'other site' relating to a similar problem. I'm now starting to wonder if this behavior might be related to a combination of the new firmware and the camera servos. Would you be willing to pull the plug on the servos and make a flight for test purposes with the new firmware?
That looked like a pro mount. I wonder how big the servos were and where he was getting the 5V from. Incidentally, when I was testing my head tracker camera the other day a servo accidentally hit it's limit. That was enough current to trip my power supply and reboot the receiver several times very quickly. I wonder if something similar could be going on with the MKs.
Ken, there's another post here (I think) where similar erratic behavior was blamed on a bad SD card. It may be something to check or keep in mind.
Last edited by a moderator:
I flew this bird to some serious altitude at the flying field on the new firmware with a camera on the mount at least a half dozen times without problems, fortunately it picked low altitude with no camera in my yard to go whacko, so I don't think flying it on .84 without the servos connected will prove much of anything. The flight controller in this Hexa is my original 2.1 and currently has 823 minutes of flight time on it. This is the first time I've ever had any problems with it in flight although it did toast the power feed diode on battery plug in second flight after I installed a 6 volt recom for the camera servos. The board went back to MK US and was repaired and tested, and I've flown it quite a bit since I got it back so I'm confident it's working correctly.
Right now I plan to do some flying with it back on .82 firmware as it proved itself to be quite stable on that version and I'll wait for a bug fix or two on .84 before I try it again unless of course it decides to do it again. If it does a repeat performance I'll take a long hard look at the Navi, compass, and GPS as those are the only new boards used in this build, everything else has a fair amount of flight time already logged in my original Hexa build pre-Driodworx HL upgrade.
Next thing I plan to do is fly it the exact same path it took the other night but this time on the older firmware and then compare the flight logs.
Ken
Doubt very much the HS 5065 servos I have on the HiSight could draw enough power to take down the F/C board so that's probably not related to what happened, at least in this case. On the other hand, I only flew it once before with the SD card installed, just got it a week ago and popped it in then. It is a brand name card and I did format it in my laptop before use, but who knows these days with so much look alike clone stuff coming out of China.
Ken
Just finished digging deeper into the OOPs the Hexa had the other night. I reverted back to .82 firmware and did a short test flight in the backyard to make sure everything was working, GPS, P/H, and A/H.
Checked the log file for any problems, looked OK, so I went out front and tried to duplicate the flight path it crashed on as best I could. Afterward, looking at the flight log I see a very different set of compass readings from the point where the Hexa went flyaway on the first flight and the same orientation and flight path on today's flight. The nick angle readings are also substantially different as well, not coming anything close to the 116 degrees of lean I saw in the first flight log. The conclusion I draw is this, if you're going to use the new firmware it is probably a VERY good thing to recalibrate the compass using the new method and the accelerometer calibration as well so the new firmware knows what level really is.
Why it should make a difference I have no idea, but obviously it does. The compass board in use in the this Hexa is new with maybe a dozen flights on it total and it was calibrated to the .82 firmware when I installed it. One would think that a good calibration would work one version of the firmware to another but I've found that making any assumptions when it comes to MK firmware can be a very dangerous thing.
Next step will be to upgrade back to .84 and do a full recalibration making sure to use the new method for the compass board and then cross my fingers and try it again. If the log of the compass readings then looks the same as it does with the older firmware on the same flight path, then I'll have to believe that compass calibration was the issue.
If you click on the flight controller radio button at the right of the screen, you can then scroll through the data display window for the F/C at the center of the screen to see all kinds of information about the board, one of them being total flight time. It's near the end of the data screens, so you've got to click through a lot before you'll see it.
Ken
Checked the log file for any problems, looked OK, so I went out front and tried to duplicate the flight path it crashed on as best I could. Afterward, looking at the flight log I see a very different set of compass readings from the point where the Hexa went flyaway on the first flight and the same orientation and flight path on today's flight. The nick angle readings are also substantially different as well, not coming anything close to the 116 degrees of lean I saw in the first flight log. The conclusion I draw is this, if you're going to use the new firmware it is probably a VERY good thing to recalibrate the compass using the new method and the accelerometer calibration as well so the new firmware knows what level really is.
Why it should make a difference I have no idea, but obviously it does. The compass board in use in the this Hexa is new with maybe a dozen flights on it total and it was calibrated to the .82 firmware when I installed it. One would think that a good calibration would work one version of the firmware to another but I've found that making any assumptions when it comes to MK firmware can be a very dangerous thing.
Next step will be to upgrade back to .84 and do a full recalibration making sure to use the new method for the compass board and then cross my fingers and try it again. If the log of the compass readings then looks the same as it does with the older firmware on the same flight path, then I'll have to believe that compass calibration was the issue.
If you click on the flight controller radio button at the right of the screen, you can then scroll through the data display window for the F/C at the center of the screen to see all kinds of information about the board, one of them being total flight time. It's near the end of the data screens, so you've got to click through a lot before you'll see it.
Ken
Ken if you had no control of the gas during the flyaway then it has to be more than a calibration issue.
There are no circumstances where the stick gas will be over-ridden...oh... except for one... As long as radio contact is established, you should always be able to drop gas to min gas and land.
I suspect something else is going on. I've seen a few similar events from other people. Has anyone been monitoring the RCG thread to see if it's been reported there?
PS. Funny thing about those MK log files. Stick gas is not recorded.
Can you upload the log?
There are no circumstances where the stick gas will be over-ridden...oh... except for one... As long as radio contact is established, you should always be able to drop gas to min gas and land.
I suspect something else is going on. I've seen a few similar events from other people. Has anyone been monitoring the RCG thread to see if it's been reported there?
PS. Funny thing about those MK log files. Stick gas is not recorded.
Can you upload the log?
Ken if you had no control of the gas during the flyaway then it has to be more than a calibration issue.
There are no circumstances where the stick gas will be over-ridden...oh... except for one... As long as radio contact is established, you should always be able to drop gas to min gas and land.
I suspect something else is going on. I've seen a few similar events from other people. Has anyone been monitoring the RCG thread to see if it's been reported there?
PS. Funny thing about those MK log files. Stick gas is not recorded.
Can you upload the log?
I think the latest version of GPX export does show control stick position but maybe not all of them, just nick, roll, and yaw? Dunno, I'd have to fire it up and look and right now the SD card is back in the Hexa, next time I pull it off the shelf I'll pop the card out and get the file off of it.
I have seen very limited reports of problems with .84 so far though I think a lot of people are waiting for everyone else to try it first. So far I haven't seen any that parallel what happened to mine though I haven't had time to really dig in and find out how many and what kind of problems are being reported.
Ken
Another Fly-Away:
http://www.rcgroups.com/forums/showpost.php?p=17681339&postcount=10933
This happened 2 weeks before the .84 update.
He lost control of the gas and had to turn the radio off to get it down.
http://www.rcgroups.com/forums/showpost.php?p=17681339&postcount=10933
This happened 2 weeks before the .84 update.
He lost control of the gas and had to turn the radio off to get it down.
Crash what did they determine to be the cause? Wonder how many guys would have been able to avoid panic and keep a cool head to cycle the TX and get the MK down avoiding a fly-away. Man I hate to see guys have a loss of control through no fault of their own. I can understand a mechanical failure but the rest.....
I'm trying to find out.
There's no more information in that thread. You can click the thread link at the top right though.
FlyEYE
Member
I had a flyaway on .78. I forgot to turn off vario atitude hold when trying to land and it started bouncing around, which I understand is normal but then it shot up full speed resulting in a crash and proof that a gopro (without case) can bounce off of 2 roof tops and down 25+ feet onto asphalt and still survive.
Last edited by a moderator: