Posts: 106 Threads: 22 Likes Received: 24 in 20 posts Likes Given: 7 Joined: Jan 2017 Reputation: 0 Can an ESC be the source of mid throttle oscillation ?
Do ESC's have a "useful service life expectancy ?
Other than moving motors from one ESC to another to rule out a potential bad motor, is there a "quick or simple" way of diagnosing a bad ESC ? (without replacing it) ?
Thanx
Danny Z ![[-]](https://intofpv.com/images/collapse.png) • Posts: 12,099 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 In theory, if you have a laser tachometer tool, you can probably see if one motor is spinning at a different rate. • Posts: 5,315 Threads: 672 Likes Received: 3,155 in 1,743 posts Likes Given: 2,030 Joined: Jan 2016 Reputation: 139 on top of my head... you might be able to tell by looking into blackbox log.. • Posts: 1,149 Threads: 50 Likes Received: 704 in 450 posts Likes Given: 1,189 Joined: Sep 2016 Reputation: 30 16-Jul-2017, 11:48 PM (This post was last modified: 16-Jul-2017, 11:52 PM by fftunes.) Hmmm... was just thinking of 2 things...
1) i once had an esc that made the motor stutter in a very small range only about 30us wide, somewhere in mid throttle area - took me a while to really notice it in motor tab, i had to increase throttle by arrow keys to find it.
2) there was a discussion a while ago that vibrations can be picked up by certain esc components and produce a feedback loop - it seemed that "softmounting" the escs would make sense... • Posts: 106 Threads: 22 Likes Received: 24 in 20 posts Likes Given: 7 Joined: Jan 2017 Reputation: 0 I fly KISS, I have bought a "data logger" from RMRC, but I am waiting for the cable to connect to the FC to come in, then I am hoping to utilize black box.
The machine in question was running smooth as silk, then about 6 weeks ago, had a low speed crash. The quad landed in a hard pack gravel road, I replaced 2 motors (lumenier 2206 2350kv), the motor bells had some good gouges in them, but still had oscillation going thru mid throttle.
I replaced the other 2 motors, still mid throttle oscillation, so I started adjusting the P gain on yaw.....no effect
Started trying different adjustments with TPA.......noticed a little improvement, not 100%, maybe 30% improvement
Then I decided to try and play around with the notch filters, I started at the KISS defaults, and started moving the notch around, still not satisfied............
any thoughts would be appreciated !
Thanks !
Danny Z • Posts: 947 Threads: 66 Likes Received: 350 in 248 posts Likes Given: 164 Joined: Apr 2016 Reputation: 34 (17-Jul-2017, 01:20 AM)DannyZ Wrote: I fly KISS, I have bought a "data logger" from RMRC, but I am waiting for the cable to connect to the FC to come in, then I am hoping to utilize black box.
The machine in question was running smooth as silk, then about 6 weeks ago, had a low speed crash. The quad landed in a hard pack gravel road, I replaced 2 motors (lumenier 2206 2350kv), the motor bells had some good gouges in them, but still had oscillation going thru mid throttle.
I replaced the other 2 motors, still mid throttle oscillation, so I started adjusting the P gain on yaw.....no effect
Started trying different adjustments with TPA.......noticed a little improvement, not 100%, maybe 30% improvement
Then I decided to try and play around with the notch filters, I started at the KISS defaults, and started moving the notch around, still not satisfied............
any thoughts would be appreciated !
Thanks !
Danny Z Have you tried soft mounting the FC? The realacc rubber standoffs from Banggood works great. Rubber inserts like raceflight is using is not as good. I have tried both and could fly with bent props without noticing with the rubber standoffs while having massive mid-throttle oscillations with the rubber inserts • Posts: 106 Threads: 22 Likes Received: 24 in 20 posts Likes Given: 7 Joined: Jan 2017 Reputation: 0 Hi Oyvinla,
I have my FC soft mounted (The rubber bobbins from RMRC)
I just ordered the cable from Flyduino, so I can use black box and maybe zero in with the notch filters ! • Posts: 72 Threads: 2 Likes Received: 32 in 22 posts Likes Given: 1 Joined: Jun 2017 Reputation: 0 (16-Jul-2017, 10:35 PM)Oscar Wrote: on top of my head... you might be able to tell by looking into blackbox log.. I'd definatly check what Oscar suggested. If there is an issue with your ESC you should see strange things in your blackbox when in hover. (mid throttle for that matter) I bet you already did this but I'd also check all the screws to see if anything got lose. • Posts: 106 Threads: 22 Likes Received: 24 in 20 posts Likes Given: 7 Joined: Jan 2017 Reputation: 0 Screws are tight, still waiting for the data logger cable to show up.
I'm sure I could have soldered the leads to the fc, but then I would have more wires to tuck out of the way when flying......
A quick side question:
I may have asked before but here goes again,
Do you always tune out all ossolations, or do people reach a point tune the best they can and live with a little mid throttle ossolation ? • |
