seattle_helo
Member
Wow. I wouldn't have thought a single motor out would cause that violent of a flip on a hexa. Ken, can you be certain the ESC didn't burn up after impact?
Not off to a good start in the new year...
- Thread starter RTRyder
- Start date
With absolute certainty, no, I can't. However the flip wasn't really that violent, it appears that way from the camera point of view because for a good portion of the initial movement it was being compensated for by the camera mount, it was only when the platform ran out of travel that the camera suddenly got jerked around with the rest of the frame making it look worse that it really was. From the ground it appeared to wobble a bit then just leaned over towards the rear and down it went. The motors were screaming like crazy trying to compensate in the first second or two and then it was down before there was much chance for anything else to happen. On top of all that as soon as I saw it was definitely going down I gave the motor stop command, whether or not it had any effect I don't know.
Ken
seattle_helo
Member
Copy that, Ken.
Sorry to see the damage Ken, glad you have a handle on what the problem was.
seattle helo I had my hex a flip back on me back in April last year when a bad solder joint on a bullet connector gave way, luckily it was just one of my first machines and only a few feet from the ground but when the rear motor stopped the hex a just flipped http://www.youtube.com/watch?v=bXHxfhzREdE&feature=g-upl&context=G245d0a7AUAAAAAAApAA
seattle helo I had my hex a flip back on me back in April last year when a bad solder joint on a bullet connector gave way, luckily it was just one of my first machines and only a few feet from the ground but when the rear motor stopped the hex a just flipped http://www.youtube.com/watch?v=bXHxfhzREdE&feature=g-upl&context=G245d0a7AUAAAAAAApAA
DucktileMedia
Drone Enthusiast
I really want to know how the WKM compensates for a motor out now. Logically speaking, isnt the whole concept of the FC to constantly compensate? This would mean that the FC does WHATEVER it takes to keep the unit level. therefore a motor out will instantly trigger the opposite motors to work harder. But the question is, does it shut down the opposite motor like some other FC's? Someone posted a video a while back on here showing just that.
quadcopters
Quadcopters.co.uk Drone Specialists
I second what Dave said , Glad you found the problem.
Geoff
Geoff
redridinghood
Member
Ken maybe the damaged esc was a result of the firmware flashing removing some overload protection thresholds. One of the reasons I changed direction and got the Herkules boards.
mitmit
Member
Sorry about your crash RT, seems all av130 bends the same way in crashes hehe)
View attachment 2003
Btw, as for hex redunancy - I had few precedents with burned in the air esc's on the flat mk hex, it did not flip and remained in the air on five engines, although it is not an easy task to land it ..
cheers
dimitri
View attachment 2003
Btw, as for hex redunancy - I had few precedents with burned in the air esc's on the flat mk hex, it did not flip and remained in the air on five engines, although it is not an easy task to land it ..
cheers
dimitri
Attachments
iceman
Member
Only an idea but could they not compensate by shutting down the opposite motor at the same time using attitude feedback? After all DJI is one of the FCs you pay the most for with the least features.
mbsteed
aerial video centric
Sorry to hear about your problems. I have gone through numerous crashes myself but on my smaller cheapter builds. Interestingly, most of those were due to ESC failure (beyond pilot error).
Ken, do you think it was a bad ESC or that the ESC was slightly underrated for the power draw? I would like to think the Maytechs are more reliable - I have those on my X8 and so far so good. I will be putting those on my octo, so here is hoping (I wish they would have had the 40A version just to make me feel more secure). Any thoughts about going to an octo configuration to try and circumvent a similar problem in the future? (although there is another thread that questions that assumption for DIJ)
Ken, do you think it was a bad ESC or that the ESC was slightly underrated for the power draw? I would like to think the Maytechs are more reliable - I have those on my X8 and so far so good. I will be putting those on my octo, so here is hoping (I wish they would have had the 40A version just to make me feel more secure). Any thoughts about going to an octo configuration to try and circumvent a similar problem in the future? (although there is another thread that questions that assumption for DIJ)
Last edited by a moderator:
Considering I had several hours of successful flight before reflashing the ESCs and maybe 1 hour afterward and before the crash it is a definite possibility. When I reflashed a brand new set of the same ESCs to use on my Droidworx AD6 I wound up with 6 useless ESCs. They all worked but no way would they all start up at the same time and the AD6 simply was not flyable with them. I reflashed them back to Turnigy firmware and four of them worked much better and two of them refused to work at all on the Turnigy code.
So to be on the safe side I'm done with the fast PWM firmware, at least for use on anything that carries a camera or costs more than a couple hundred $. I just came in from the first truly successful test flight of the AD6 now using a set of Exceed Proton 30 amp ESC's, ridiculously inexpensive and they seem to work really well. The Protons are another branch of the Hobbywing line, the Turnigy Plush programming card I have worked to do the basic setup so obviously the same hardware and circuit layout.
I'd consider a solution along the lines of the Herc if there was a hex specific setup that didn't wind up costing $1000 US.By the time you get that, the WKM, plus all the other bits and pieces, well, I might as well build another XCell Spectra G heli and use that, it would cost less and be more reliable. I kind of regret selling the one I had to build a second MK...
Ken
seattle_helo
Member
Ken, just to clarify, did the fast PWM firmware improve performance? If so, will you miss it?
It didn't improve performance as much as it smoothed out the response, didn't have enough flight time to really be able to compare video done before and after, that was what I had hoped to do the day it crashed.
How much I miss it depends on how well the Maytechs work once I get them installed and the gains dialed in again. I think I'm just going to go back to the best setup I've had so far which is the one I used when recording the video at the sheep pasture, the CineStar just flew so well that day that I somewhat regret making any changes afterward.
Ken
seattle_helo
Member
Understood. What happened with the quad that got dunked? Were you able to dry it out?
The quad should be fine. I put it on a shelf under one of the heating ducts, should probably put a battery on it and try it out today. Pretty simple setup, KK board with 4 ESCs and motors, other than water getting under the shrinkwrap on the ESCs not much else to worry about, a little WD40 in the motors and relube the bearings, go fly...
Ken
I would be very careful using dunked ESC's, they could have corrupted firmware during the dunk/short. Give em a good test over time on the bench first.