Nimbus Tricopter VTOL

what if i use 14x5.5 Carbon Fiber Propeller on front and 17x5.5 for rear is it ok? or i use 15x5.5 on front

Foxtech used props with a higher pitch on the front, ie 13x7 or 14x8 for better performance at the faster speeds of forward flight, so 5.5" pitch might be too low for the fronts. I donā€™t remember what Kv motor is on the default Nimbus but you can look it up. The rear is different from the front motors and thus can use a larger prop. You can try 15x5.5 on rear but not ideal for the fronts.

notedā€¦ i will find it firstā€¦ a little bit difficult to find a pair 14x8 prop

Musa is using 3520 720Kv motors instead of the 3520 520Kv motors we are using up front so there needs to be some caution on selecting the prop size. His Kv is higher.

By using the Foxtech or SunnySky 3520 520Kv motors, the Gemfan wooden props fit right on the M6 adapter. The props come in CW and CCW versions and have a higher pitch for plane forward flight. Remember that you are only hovering for short periods and flying for long periods.

maybe i can down size a little bit for frontā€¦ let say 13x08?

Yes, it says that for a 3520 720Kv motor, a 12x6 prop is good for a 6s battery so I would try the 12x8 wooden propā€¦or a 12x8 prop that has both CW and CCW versions.

thank you @GregCovey, unfortunately i canā€™t find it at local store hereā€¦ i have to wait it around 3 weeks for purchasing it overseasā€¦

@GregCovey, @Graham_Dyer i think i found what the problem on my test log #4 https://www.youtube.com/watch?v=oUXMEVNSz2U
the key is in minute 0:47 and minute 1:33
the sound like barking, is because the motor choked up, here is my scenario :

  1. when itā€™s Qstab takeoff throttle increase gradually from low to high until itā€™s fly and ready to transform to plane
  2. when itā€™s complete fly in stab mode, rear motor is off
  3. when itā€™s back to qstab again ready to vlanding, rear motor turn back ON and JUMP to HIGH SPEED (not gradually increase)
  4. when rear motor jump to high speed the result is motor choked up / not running smooth
  5. after itā€™s crash the motor back to low speed and run normally again

soooā€¦ i test this scenario by put high throttle direct to rear motor from stopā€¦ and the result is same like when itā€™s crashā€¦ barking and choked upā€¦

in previous maiden flight (test log #3) i was succeed test full cycle flight from vertical taking off, stabilize flight until vertical landing using Xrotor 40a ESC (even using only 1045 propeller for all), but in the same day one of my xrotor 40a is error. so i fix it by replace all esc using 60a opto ESC and like u all know itā€™s turn become disaster in my next flight attempā€¦

soā€¦ what is still question to solve is, ether itā€™s because the AMP different (40A to 60A) or itā€™s because itā€™s OPTO ESCā€¦

Musa,

It looks like the motor becomes out of sync with the ESC. What model is your 60A ESC?

Why did you select the 3520 720Kv motor instead of the 3520 520Kv motor that we are using?

Iā€™m using ZTW SPIDER 60A OPTO ESCā€¦ and why i use 720KV is just because i have stock motor for that and curious whether is it run or not using this motorā€¦ curiosity it turned out to be expensive hehehehe
but it seems like it you guys already have the best configuration on itā€¦ so next time i will built the right oneā€¦

I think you are close to having it work but need to adjust parameters in the ESCs, if possible. The older ZTW Spider 60A Opto ESCs used SimonK and the newer ones use BLheli One-Shot. I am not familiar with changing the parameters.

You could try just swapping out the rear ESC with a Hobbywing XRotor 40A ESCā€¦or swap all 3 ESCs since they are inexpensive. Remember that the hover current is about 30amps total using the 520Kv motors or about 10amps for each ESC. The reports have these ESCs running cool temperature. So your higher 720Kv motors will draw more current but probably still be a good match for the XRotor 40A ESC.

Food for thoughtā€¦

i think, i will back to xrotor 40a rather than messing with parameterā€¦

Personally, all this is pure conjecture until you can present log from a flight for analysis. Youā€™re still not able to say what the battery voltage and current draw were when the back transition completed. Gauging from all the videosā€™ audio, you seem to have all the voltage during takeoff but not there in the back transition.

Good luck.

Has anyone managed to make flight takeoff, mission and rtl completely autonomous?

Yes, Iā€™ve done it quite a few times.

Is this Nimbus good for mapping aero with micasense?
Or sign another wing?
I want to map about 180 hectares per flight

yes uā€™r rightā€¦ unfortunately i have problem with logā€¦ i donā€™t have any log on my every flightā€¦ maybe there is some miss setting or else on my pixhawkā€¦ however i do another way to analyze it for nowā€¦ at least it help me to know some of the gauge to match with the flight characteristicā€¦


i do have try re setting the log parameter and format my sd card but the log seems didnā€™t workā€¦ maybe i have to swap my pixhawk FC to fix thisā€¦

Musa,

Try using a different sd card and make sure that it is a good quality class. I use the SanDisk - Ultra PLUS 16GB microSDHC UHS-I Memory Card in all my Pixhawk v2.4.8 FCs.

I didnā€™t see any issues in your video Log #6. All three flights looked good.

Cheers!

@GregCovey yes, i have plan to change the SDcard after last flightā€¦ the only issue in the log #6 is only minimum threshold of the esc didā€™t match with minimum threshold of the RC controller, is too highā€¦ thatā€™s why i need to re calibrate the ESC max and min threshold againā€¦

does anybody know INS_ENABLE_MASK for?