Today I was getting some foggy sunrise shots. About 2 minutes into my flight, my CS8 pitched hard and I could hear the motors were doing some very sporadic RPM changes. Fortunately I was low enough that I could get down with no damage (except whatever damage a racing heartbeat does). Anyway, seems like an ESC problem as I had a solid red light and fast audible beep under the BL at motor 6. I unplugged the battery, and plugged it back in...interesting that the 'dead' motor switched to 7. This is about when I smelled and saw a tiny puff of the evil white smoke. Went to analyze the GPX and my last recorded GPX file is 20121103. The card is not full [Capacity :1 GB (1,000,275,456 Bytes) Format :MS-DOS (FAT16)Available :936.6 MB (936,607,744 Bytes)]. Any reason it would have stopped recording data? Or is it possible that it is the right flight data but wrong date? I can open this file in the GPX_viewer but in the version of GPX_Tool that I have (MK_GPX_0016) didn't seem to load it. GPX is attached in case there is a way of determining if date is wrong.
Latest tool is MK GPXTool V1.2.1.0 Download at http://www.mikrokopter.de/ucwiki/MKGPXTool?action=AttachFile&do=get&target=MK_GPXTool_1.2.1.zip Opens fine in this version.
"Foggy" sounds a little dangerous. I am super spooked about any kind of moisture, as most of the components on my copter are completely exposed. And with the heat that's generated, and with all the voltage surging around in that thing, seems it wouldn't take much to short one of the motor leads, for example. I wonder if that's what happened?
I posted this reply yesterday in another forum member's posted issue. I'll copy/pasted here: "I would suggest some sort of cover (for MK electronics) In fact I would suggest everyone cover their MK electronics. I could not imagine flying with my PCBs so exposed like some of the builds I see A single drop of moisture and down she comes...even on a bright sunny day there could be random droplets of moisture in the air...ask me how I know! Not saying this was the cause of your crash but I bet some unexplained midair shutdowns could be attributed to exposed electronics and the evil they sometimes attract." As state by Holger, MK ESC are especially sensitive to ANY moisture and humidity. I would suggest using a conformal coating for your ESCs I may post the same copy/paste message from time to time so get use to it folks!
Gary: Franco Sapin (author of MK_GPXTOOL) went to some trouble to add logic so that it can handle "illegally" terminated GPX files -- it's not as pedantic about the so-called markup-language and can handle those files that are incomplete because of uncommanded terrestrial or arboreal encounters. Andy.
Happened to me just because a light dew that condensed on the PDB. One motor wouldn't start (until I got back to my workshop, that is). Andy.
The date (from the GPS) is 2012-11-03, 17:43:24 Zulu (aka Greenwich). So this is not the flight you did today. What was the name of the folder in which you found this GPX file? That's also derived from the GPS date. Andy.
Thanks for the help. Gary, I can't get Wine to Launch that version of GPX Tool. Is there any indication that the dates are wrong in the log? I am already planning what I can fashion to protect the ESC from a similar problem. Have you seen THIS product? I wonder if there is the possibility that this could be applied to exposed electronics to protect them?
Sorry, I was asking what was the actual value of yearmonthday? That's read directly from the NMEA packet from the GPS -- so the date is more or less guaranteed to be accurate unless the U.S. military diddles with it (they control the GPS). Andy.
Duane, the most recent version of Wine won't run the MK GPXTool. I tried again last week and it won't start up. The GPX viewer works but the Tool is much better with analysis and windows. I run VMWare Fusion and only use it on my personal machines for these types of situations.
Bootcamp works for me. I had "issues" with VMWare and USB drivers....they'd occasionally uninstall themselves. This was on an MBP 17". Andy.
According to MK Tools, my time is correct - GPS UTC TIME Date: 01/26/2013 Time: 08:29:xx.xxx Any suggestions as to why it wouldn't be writing my GPX info to the MSD card?
My guess would be that the GPS board had not established a GPS Fix before you started the motors and the throttle value exceeded the threshold that says that the copter's flying. I had it happen on two occasions on the same day -- both at separate locations. I simply hadn't waited long enough with the copter powered up for the GPS to get a 3D fix. Verify that you have the microSD fully installed and latched in the socket. If you want to test it indoors, take the props off, let the GPS get a fix (flashing blue light), and then throttle up to 50% for ten seconds or so. Then shut it down and see if you get a GPX file on the microSD card. I can do this in my shop only because the GPS can get a six satellite fix through the roof of the building (flat roof, timber construction)....if you can't get a fix, then just take the copter outside. You don't actually have to be flying -- you just have to spoof the Navi board into thinking that you are -- and that's done with the throttle setting. Andy.
Two things: Check the solder joints on the microSD card slot...could have come loose re-format the microSD card and verify that you can copy files to it on your computer
Duane Andy mentioned on another thread that the GPX file isn't created until motor start and throttle above 40%(?). So if you have the props off just run it up and then check it.
I d id this last night. Verified that I was getting satellites inside, removed props, ran up waited for a while, shut down, no GPX. The thing that baffles me most is that my last GPX file was in November. I'll disassemble tonight to check soldering on the SD. I will also reformat the card and retry getting a fix.
I think when you open MK Tools there's a terminal view, and if you watch it when you power up the copter, there's an "SD CARD OK" or something that spews out. It'd be interesting to see if that appears, and if the Navi board even sees the card. I just ran a test to see what it looked like with and without a card. See the screenshots below.