XAircraft Interpreting Black Box Data

Av8Chuck

Member
I just built a Y6 and made some changes between these two flights, I don't know how to interpret this information to determine what, if any adjustments I should make to improve it.


Flight 1: with 2-axis gimbal and GH4
http://log.xaircraft.com/report.htm#2014_10_16_182651.000_16.1.01.00

Flight 2: with 2-axis gimbal and NEX -- I had also leveled the motors.
http://log.xaircraft.com/report.htm#2014_10_16_182651.000_18.1.03.52

Any help and explanation of how to read the data would be appreciated.
 

dazzab

Member
What I look for mostly in those reports is the motor graph. In the first one your motors are all tracking together. But in the second one 1,3,5 are lower than the others which I think indicates an issue with balance perhaps? But overall the reports look good to me. The vibration levels could be a bit lower but they aren't too high. And your hover rates look great.
 

kloner

Aerial DP
motor alignment can be better.... i think, never messed with coax and superX but there is a good gap between the clock/counter clock, maybe somebody with a coax can confirm that it will show closer than what you have there. the first graph looks more normal but how the counter rotating motors on the second one are more grouped like when you look at min/max throttle from the imu

Biggest thing i see in that is the vibration levels. Either balance the props or get the imu on a clean plate or both.

the motor/prop combo looks good for the payloads lifted

you didn't show the other page you start at with the g-knob setting. what is the g knob set at?
 

mediaguru

Member
Yes one of the things I look at most is motor percentages. Your first setup appears to be better, with a tight grouping of motor outputs in average and max. 2nd group there is a much bigger difference.
 

Av8Chuck

Member
Wouldn't you know it, the second flight is the one after I leveled the motors… I'll see if I can't figure out how to improve that.

G is 55-65%, I upped them to 116% using the knob but it oscillated. The gains are set to .8 in the GUI and its not as locked in as my quad. Should I up the gains in the GUI to something like 1.2? Does the gains adjustment on the Tx change the gains set in the GUI or is like an outer feedback loop where you adjusting the secondary sensitivity?
 

kloner

Aerial DP
that's opposite of how you want to treat it.... get the g knob to 20%, raise the basic gains in gui to about 1.1 to 1.2 and it should settle in for ya.

g knob is like atti gains on dji, the gui gains are like the basic gains on a dji. there individual seperate settings
 

Old Man

Active Member
Here's a tip, a coax with quad style countering corners is most efficient if all the motors are canted a couple degrees clockwise. The upper props send a cone through the lower props, leaving the lowers to generate higher wattages when everything is at a 90. The balancing act does not work if using the DJI method of all tips going one way with bottoms going the other. That's why the first run worked better.


Sent from my iPhone using Tapatalk
 

Av8Chuck

Member
that's opposite of how you want to treat it.... get the g knob to 20%, raise the basic gains in gui to about 1.1 to 1.2 and it should settle in for ya.

g knob is like atti gains on dji, the gui gains are like the basic gains on a dji. there individual seperate settings

Thanks, that's kind of what I thought.

Here's a tip, a coax with quad style countering corners is most efficient if all the motors are canted a couple degrees clockwise. The upper props send a cone through the lower props, leaving the lowers to generate higher wattages when everything is at a 90. The balancing act does not work if using the DJI method of all tips going one way with bottoms going the other. That's why the first run worked better.


Sent from my iPhone using Tapatalk

If I understand you correctly, SuperX is weird when it comes to Y6 because all the tops are CCW and the bottoms CW, I was expecting it to be more like you described. I haven't setup my X8 yet.
 

DannyC

Member
Bumping this thread. I have a couple lower end quads. Nano's and micro's. I upgraded to what I'd call a big boy quad and while I was learning, it fell like a ton of bricks from 40 ft in the air. The black box report is attached.

http://log.xaircraft.cn/#2015_04_11_083929.705_36.3.02.24
http://log.xaircraft.cn/report.htm#2015_04_11_083929.705_36.3.02.24

A couple things I noticed. The flight mode popped to manual for a brief moment when I crashed. It has done this before. My motor outputs....are they normal? They don't seem very tight, but again, I'm a noob.

Lastly, the vibration seems to be crazy high. I recently balanced my props. I suppose I need to balance my motors also. What else could allow this much vibration? (Up to 6 G's)

I've seen a couple other vibration patterns and they are usually under 1 G.... I'm way off that.

Any help is greatly appreciated. Thanks!
 

mediaguru

Member
Looks just like my logs when this happened to me, twice. I assumed it was user error both times. Fortunately my bird recovered in time both times. One time I was some 750 feet up and it fell about 500 feet before recovering.
 



Go4d

Member
Hello DannyC
You are right, the log is not working, it appears that the black box site is down or something is wrong…,I also can not see my logs... I will check later and post a new log.

I am using a SuperX, not a MiniX. I also had to send back a MiniX that was not working out of the box, led turned on and off erratically.

About the Dubro foam, I have had bad experience using it, I once use it on a wookong and it affected a lot the stabilisation, since it uses the frame as feedback, if you isolate it, the correction will be a bit late and this can produce oscillation. I am not sure if this could be the case for SuperX.

I am looking on Tunning my quad rather than changing to another system like the pixhawk, this is why I am asking for some input to correct the system that I already have. I appreciate your recommendation.
Regards.
 


Go4d

Member
Hello Guys, servers are now working, logs should work. Please let me know what you think I can tune.
Regards
 


fltundra

Member
Hello Fltundra,
No I am not a US rep for Xaircraft… I am just another SuperX user, I just need a little help to tune my system, and I was hopping to get some help here.

Here are my logs, I hope someone can help me figure out what is causing my vibration problem.

Logs:

http://log.xaircraft.com/report.htm#2015_06_26_143507.500_59.12.04.14

http://log.xaircraft.com/report.htm#2015_06_26_143507.500_59.11.02.29

Regards
Where are you at on gains? Roll and yaw look a little high. Have you balanced the motors and props together?
 
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Go4d

Member
Hello Guys,
This are my gains:
Roll 1.0
Pitch 1.0
Yaw 1.0
Height 1.3

on the futaba radio the gain knob is at +38

As you can see I did struggle to maintain altitude.

My props are balanced and the motors are new, I am not sure how to balance the motors, but I guess they are balanced since they are new.
It is a big quad, I am using KDE's 4014- 380 kv 17 inch props.

If I increase the gains it seems to vibrate more. Please advise on what you see on the logs.
I appreciate your help.
Regards
 

fltundra

Member
Hello Guys,
This are my gains:
Roll 1.0
Pitch 1.0
Yaw 1.0
Height 1.3

on the futaba radio the gain knob is at +38

As you can see I did struggle to maintain altitude.

My props are balanced and the motors are new, I am not sure how to balance the motors, but I guess they are balanced since they are new.
It is a big quad, I am using KDE's 4014- 380 kv 17 inch props.

If I increase the gains it seems to vibrate more. Please advise on what you see on the logs.
I appreciate your help.
Regards
I am also using kde motors and they are perfectly balanced, so your best bet is to put more time into the props and to get a good read on your log file you need to hover out of ground effects in absolutely no wind to be able to tell vibs, motor alignment and degrees a second (gain). Being that your swinging 17's makes a little tougher to get right. Also make sure your cg is perfect. i would leave the gains where there at for now.
What are you using for props? And to balance them? And check motor alignment.
 
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Go4d

Member
I am using CF T-motor, I have a magnetic balancer., For motor alignment I used a rig with digital inclinometer.
Any other ideas?
thanks
 

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