I have had this strange effect now twice.. Both times in windy conditions so its almost hard to distinguish if its the wind or the Helicopter causing the right bank.. The strange part is that it decides that a 10 deg bank is level.. With a constant left roll input it will hold that position and fly normally.. Almost as if the trims are off all of a sudden.. I also get a strange left yaw.. Anyway my suspicion is that motor/blc is going out on the Right side (Motor two or thee on my 6).. But I can't seem to see the evidence in the GPX files.. Can anyone help me look for this issue?? Much thanks, Cedar
So if you look at the virtualOSD the heli almost always thinks its banked to the left... This would explain the right correction its trying to hold... ????
Cedar have you checked your MX-20 to make sure that the stick calibration hasn't somehow gone off of center?
I have checked and centered my trims in KopterTools (using a Futaba 9C with Dragon Link UHF).. The strange thing is its not all the time ie. when I take off its fine..
I'd run some diagnostics on your FC board. Have you calibrated the gyros lately? It could be a loose connection, a failing gyro, or even a vibration problem. Do you have another FC board to swap out? I had a similarly weird problem once and I found that 3 of the 4 mounting screws on my FC board had worked their way loose, and it was flopping around a bit.
So in file 003 motor 4 is running on average about 1.5amps higher than the other motors. The OSD shows a slight bank to the left through nearly the entire flight. What is a bit troubling is that at about second 94 you are making a turn and boom one comes around to a 240 heading and the nose dips down and runs at a 20 degree nose down. Which I would assume means the wind was pretty strong out of the west. File 005 shows nearly the same behavior. Check out hte OSD a 129 second mark. Nearly 90 degree left hand bank. This would be a guess but do the battery tray/bubble level ACC calibration. And if you have a couple of flights immediately before these where you think it was normal send those files over. FYI though you weren't using GPS the solar index about the time you were flying on the 10th was a KP of 4, in the yellow range. That shouldn't have any effect. Lastly what batteries were you running. Voltages are low, almost looks like 3S.
Hi Cedar: Looking at the GPS00005.GPX file, a couple of things seem odd: 1. The Virtual OSD shows that copter is rolled to the right most of the time -- that's derived from the Roll Angle. Now maybe I've got things wrong, but I thought a +ve roll angle in the GPX file corresponded to a roll to the left....but what I'm seeing in MK_GPXTOOL is that a +ve roll angle is showing on the Virtual OSD as a roll to the right....(I'll have got it wrong on my new DVD set, A Rather Good Beginner's Guide to MK_GPXTOOL and Google Earth. Sigh.) EDIT: Gary's right -- duh....it's a bank to the left on the Virtual OSD. What am I thinking. This vacation stuff is addling my brains..... 2. Motor #4 is working much harder than all of the other motors. For example, at second 44, the numbers are (in Amps): 6.4, 8.6, 8.5, 12.3, 8.5, 8.6 3. Apparently in contradiction to the above, the BL-Temps do not seem to correlate: 43, 45, 45, 44, 54, 59 This makes me question the accuracy of the current reading.... To augment what Steve said, I think you might want to recalibrate the ACC again. The gyros you'll recal before each flight. Sorry I can't be more specific. Andy.
Gary: On the #5 GPX file, I see the voltages started at 15.9, declining to 14.5 -- that seems normal for 4S, so I'm puzzled by your observations regarding low voltage. Andy.
OK. I had a problem with that file -- I think I need to re-download it - MK_GPXTOOL only showed me 10 seconds or so of flight... That sounds low as you say. Andy.
Thanks everyone for analyzing my flights.. Attached are the two flights before that I had no problems with.. They were in the trees and had no wind.. The low voltage flight was a second flight on the same battery.. For some reason I'm not seeing the first two flights of the day in the gpx files.. I'm using the turnigy 5600's and the Zippy 8000's.. I just scoped the flt-ctl in MK-tools and all seems normal. I'll do the "the battery tray/bubble level ACC calibration" and try a couple of flight in the morning.. I have checked my physical connection of the board and its solid.. I did check motor temps and they were all similar and nothing out of the norm.. (felt by hand.. Not even warm)..
Just remembered it did a similar thing this morning.. See attached file.. Interesting google view anyway.. If you look at trackpoint #212 I'm drifting fast to the right when the virtual OSD says I'm level.. ie. banked hard right is the copters happy place?? Just wondering what is the width of the line on the map represent? Here is the video from this flight..
I think the width by default is altitude. There is a spot where you can set it. Or is it ground speed. I'll look again in the morning.
Hey Cedar: Do you happen to have the MK Tool option set that will inhibit you doing a motor start without a GPX fix? That's the only time with the earlier versions of the firmware where I've flown and not got a GPX file. The current version of the firmware only requires that the system can get the date/time from the GPS so you don't even have to have a 2D or 3D fix. Andy
Ok so I finally got around to test flying and It looks like I have solved the problem.... The last thing I did to the helicopter involved taking the mount off.. In the process I didn't secure the servo wire from the mount to anything but the flt-ctl board (I use the mk for tilt). I did check that everything had enough slack to not pull out etc. BUT it was pulling on my board just enough to tweak out the orientation of the flt-ctl.. So the reason that it would only show in windy conditions is that the Radian never "pulled" on the board in calm conditions.. Incidentally the board was also being "twisted" slightly causing the random yaw.. So now I have the servo wire zip tied to the vertical battery post and then down to the mount.. Thanks again for looking at this.. Cheers, Cedar