Thank you for your explanation . I will be more carful in the future.
I will carefully continue to progress a little at a time. I feel that I’ve come pretty far considering. I appreciate everyone’s assistance.
Rick…
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Dave, I have gotten to the point where I was beginning to do initial adjustments to do a maiden test flight, when all of a sudden the BATT1 low voltage error appeared again. But this time the 2 ea 6 cell 6000mah. LiPo’s in parallel where fully charged and it was reading on the MP Data screen 16.42 volts? Could the PM02 power monitor be defective?
Measure the battery voltage with a meter and then reset the “measured battery voltage” from Mission Planners Battery Monitor config screen.
Dave, I have been able to correct the issues I’ve had and tested with a tethered quad. The 2 starboard motors motor 1 and 4 are not coming up to speed while under PixHawk control. I hooked up a 4 channel scope to view the PWM signals and those 2 lag in RPM. I checked each motor individually using a Spektrum Servo tester, and set the pulse timing to 1520ms. All 4 motors spin at about 9100 rpm. The signal out of the Pixhawk is suspect. Is there an ESC calibration that will correct these 2 lagging motors?
Thanks.
This is a waste of time. Remove the tether and follow normal configuration procedure.
Was able to fly today. The problem I was having with 2 motors not doing their work was that the calibration that requires you to place the pixhawk in 6 positions wasn’t done. I did the calibration again, and the motor response got corrected,
When test flight was done, the quad still wants to slightly right bank and forward drift. When I did the cal. It was free hand and may have not been real still when the button on MP says press continue when done. Dave, how sensitive is that calibration should it be completely level and still when this test is done?
Do you recommend redoing this procedure? Will auto tune help in making a hover rock solid?
Yes, use some reference surfaces for the positions (table and a wall, floor and wall, whatever). And then when it’s complete run Calibrate Level and make sure its level in Mission Planner’s HUD.
I doubt you are anywhere near ready to run Auto Tune. Complete the process here: The Configurator
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Dave, did the accelerometer calibration again, and test flight was 100% better I could POS HOLD almost rock solid. Question. On the MOT_HOVER_LEARN parameter, How long should you fly to collect good data? Or can you keep it on always? Does it now sound to you that I am ready for the autotune flight?
Also, I have 15 inch props and the distance between motor centers is about 18”
Remember these are power arms from a DJI S900 SPREADING WINGS bird.
Will the ALT A function in MP work for all versions of MP ?
Thanks,
Rick…
Rick-You can leave it on. The only good reason to disable it is if the Hover value is below .125, doubt that’s the case for you.
Vibe levels good?
Have you configured the notch filter?
Performed Magfit?
Checked outputs for oscillation?
All pre-requisites before running Auto Tune.
Thank you for the action list. I appreciate your time and help.
I read somewhere that autotune can worsen controls. Not sure what to make of that, it I think that I should leave well enough alone. I will perform the suggested steps. But again when I placed it into Position Hold,about 30 ft high,
It was Rock Solid in the sky, hands off on controls for a good 15 seconds. Solid. Should I still do AutoTune?
I know I’m not completely there yet, I feel that for a 70 yr old Veteran, who worked in electronics in the 70’s and 80’s, I’ve done pretty good with this auto pilot system. I need to slow down and take these last steps
Extra slow, any missed parameter at this point can cause irreparable damage at the end…
Again, I totally appreciate your taking the time to help an old man……
Thank you…
Rick…
It can if the craft is not at a tune state suitable for auto tune. A message of “failure to level” is the usual hint that it’s not configured for successful auto tune.
If you want to post a link to a .bin flight log of a short flight with hovering and a bit of pitch and roll we can see what needs to be done.
Okay, on Friday I will have the time to do the homework you’ve given me.
It won’t be till next weekend before I can send the data.
Thanks…
Rick…
This shows the craft is underpowered/overweight with a Thrust Loess error in the log. This could be a problem under flight demands and may present a problem when attempting Auto Tune. And before we can check the Notch Filter setting you have to change these parameters:
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
The vibe levels are good. Can it lose any weight?
I noticed that the battery is sagging quite a bit for a short flight.
And don’t bother with Position Hold, use Loiter instead.
Dave. I appreciate the input. We where testing with batteries at about 65-70%
This configuration I have is the remains of my 9 year old DJI Spreading WINGS S900. It the crash, I was able to save 4 arms. It looks like the S900 now, but with just 4 motors. I did install 2 ea 5200 mah 100c lipos. I can try Flying with one. There goes my flight time. I tested this config by placing 4 pavers on the frame, and proceeded to apply throttle and at a point just above 50% it wanted to lift the bricks. Could the fact that the batteries were NOT fully charged, cause those readings?
P.s. the pavers weighed 14 lbs.
Thanks,
Rick…
Yes, but I still think you will have to lose some weight either in battery or payload. You do not want a thrust loss error at anytime under any circumstance. That means an output is driven to max and then stability and control will be lost.
If you want to check this for yourself graph thre RCout’s in the log. At Hover you want the average output to be ~1500µs or less.
Okay thanks Dave, I will remove one battery and see what it does.
Will keep you posted.
Thanks.
OK. Make those parameter changes so data is collected for the notch filter config and we will take a look.
By the way… did a weigh in 11 lbs.= frame plus 2ea 6000 mah 6S lipos
I think we found some LiPos that are 120c 6S 10,000 mah and weigh in at 2.3 lbs.
Just to give you an idea of its size. I think you nailed it on the head. Gonna take your advise and lighten it up.
Will rerun test and log with all at optimum conditions.
BTW. The present 12,000 mah weighs in at 3.51 lbs.
I should be able to save about a pound.
Thanks…
Dave, I forgot to ask, how can I get the color graph that you sent me to view.
My helper with this project pointed out to me the data that we can use from that chart, and would like to know how can we process that .bin file to see the graph?
I appreciate it,
Rick…
Rick…