Advise and help needed. Quadplane accident.

3691366881?profile=original

Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it highly if somebody with experience could look at the log and maybe advise me on what went wrong.

Firmware: Arduplane 3.8.4
Airframe: XUAV Talon 1718mm with 150mm wing extension each side
Power: Tattu, 10000mah, 6Cell, 22.2V, 25C
Pusher Motor: Maytech 3548-790-S, 790Rpm/V, 717watt
Pusher Prop: 11 x 8.5
Pusher Esc: Castle Creation Edge Lite 75
Quad Motors: 4 x KDE Direct 4012XF
Quad Props: 4 x KDE 15.5 x 3.5
Quad Esc: 4 x Castle Creation Lite 50.
Auto Pilot: Pixhawk with Power Block.
GPS & Compass: 3DR UBlox
Servo Rail Power: Separate 5 volt, 20 Amp Ubec

I took off in QLoiter and climbed to approximately 30 meters. Switched to FBWA and applied throttle. The transition was extremely smooth but soon afterwards almost seemed that when the quad motors stopped the rear pusher motor also stopped. Switch back to QLoiter and the quad motors started up and she stopped for a moment but then became completely unstable and gravity was declared the winner.

The parameter file is attached and the log file is available at: 

https://login.filesanywhere.com/Login.aspx

Log in Name:   mp@cointech.co.za

Password:        Cointech1

Best Regards,
Marthinus

Talon 23042018.param

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

  • I've built a couple of quadplanes now and the issue of current draw during transition to forward flight seems to be an issue that requires careful planning. In one of my builds I went as far as separating the vertical lift motors off to their own circuit and use a 6S high C battery to keep the current draw down. I run the forward flight motor off a 4S battery. I've just finished helping a friend build an X6 where we used a single circuit and 4S. We are testing with a Nanotech battery which has a very high C rating. Here's some info on my older builds if interested 

    A Tale of Two Quadplanes

    A Tale of Two Quadplanes
    When a friend offered me a HobbyKing Dark Wing, I jumped at the opportunity to build my first quadplane. Being a bit smaller than an X8 and construct…


  • Marthinus said:

    Marthinus said: I think the major problem that happened is that if I calculate the max amps that all 5 motors draw it is about 180amps and the power board can only handle 60 amps. If you add the VCC 5 volt supply to the Pixhawk to the graph you will see there was a serious dip in the 5 volt and I believe that the processor reset.

    Nice job for motors mounting !
    Your quad motors have a good efficiency .

    During QLoiter hover, your motors required 33,4 A , 728 Watts , while taking altitude in QLoiter 39 A , 833 Watts.
    The plane motor with that propeller should use just 6,2 A to fly at 67 km/h - 18,1 m/s
    So in theory 45,2 A would be enough to make the transition , 40A if you are in hovering.
    Roughly even with full throttle at plane motor you should have , according to E-Calc, a total of  39+81 = 120 A .

    At transition  to gain speed from 5 m/s while your plane was in Qloiter, still taking some altitude , the Auto Pilot when the transition start  add 20 A because of  full throttle at RcOu.C3 so you reach 59A .
    That is an interesting point , in theory your plane motor should have draw much more Ampères at full throttle but it did not.
    The reason was that the  plane Esc  was starting to limit current because of low battery voltage ?

    My suggestion is to replace the battery with one with higher C rating and if you can start the transition to FBWA gaining some speed while in Quad plane mode to reach 10 m/s , it should help a lot to reduce current drawn.

    I do not think that the processor reset since you have no "holes" in dataflash log recording.

    5,2 Kg is quite a lot for the Talon even with wings extensions, it would be interesting to see how it flies when in FBWA mode and how much drag add the quad stuff.

    Advise and help needed. Quadplane accident.
    Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it…
  • 3702425097?profile=original

    1mm Carbon sheet machined and the bottom side sanded to be course. The wing area also sanded level and straight. Glued with epoxy resin.

    3702425292?profile=originalMachined 16mm clamps from alu and a m3 threaded strip from steel. The steel strip was glued to the bottom of the carbon sheet before I glued the sheet to the wing.

    3702425320?profile=original
    Motor mount same clamps but with a 2mm and 4mm carbon plate.

    The 16mm tubes are slightly flexible and next time I will use 20mm, very little difference in weight. The wings flex alot so I put a brace from the left front motor attached to the right front motor supported on the nose of the fuzz and that stopped all flexing.

    3702425208?profile=original

    This was after the crash, actually very little damage. I think the major problem that happened is that if I calculate the max amps that all 5 motors draw it is about 180amps and the power board can only handle 60 amps. If you add the VCC 5 volt supply to the Pixhawk to the graph you will see there was a serious dip in the 5 volt and I believe that the processor reset.
    Luc Maximilien said:

    Glad you did it !

    What is your AUW ?  4300 grams ?

    I'm curious about how you attach the carbon tube with  motors , can you show a photo ?

    Advise and help needed. Quadplane accident.
    Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it…
  • AUW = 5200g
    Will send some picture of mounts later.
    Have a good day!
  • Glad you did it !

    What is your AUW ?  4300 grams ?

    I'm curious about how you attach the carbon tube with  motors , can you show a photo ?

  • Dear Luc,

    Thank you for all the help. I install 2.0.25 for MAC and it works perfect. I appreciate your help.

    Luc Maximilien said:

    I use the 2.0.25  version of Apm Planner 2 on Linux Mint  and Windows 7 64 .

    The  available  32 bit version for Windows is not the latest and have some bugs.

    Advise and help needed. Quadplane accident.
    Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it…
  • I use the 2.0.25  version of Apm Planner 2 on Linux Mint  and Windows 7 64 .

    The  available  32 bit version for Windows is not the latest and have some bugs.

  • Dear Luc,

    I downloaded AP 2 and installed but receive the following error when I try to load the .bin file.

    3702425010?profile=original

    Luc Maximilien said:

    The graph was made with  Apm Planner 2

    The Rc3 output shows full  throttle command to the Esc but you gradually go to zero Amps so I think it was the Esc

    Advise and help needed. Quadplane accident.
    Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it…
  • The graph was made with  Apm Planner 2

    The Rc3 output shows full  throttle command to the Esc but you gradually go to zero Amps so I think it was the Esc

  • Dear Luc,

    Thank you for this information. I will download the log files from the ESC's and look what they did. What app/software did you use to create this graph?

    Luc Maximilien said:

    3702424651?profile=original

    Advise and help needed. Quadplane accident.
    Hi, I am reasonably new at this and had a mishap with my quad plane yesterday. I am not at all proficient in the log analysis and would appreciate it…
This reply was deleted.

Activity

DIY Robocars via Twitter
RT @chr1sa: The dev team is having fun with virtual @DIYRobocars track generation with Unity on the @donkey_car discord: https://t.co/l0Jd9…
yesterday
DIY Drones via Twitter
Review of the new Nivida Jetson NX for robocars https://t.co/bWjd3sH2o4
Tuesday
DIY Robocars via Twitter
RT @chr1sa: My review of the new @NVIDIAEmbedded Jetson Xavier NX in robotics and @DIYRobocars applications https://t.co/O7TfJZhiF9 https:/…
Monday
DIY Drones via Twitter
RT @chr1sa: Somehow I missed this, but last week @Nvidia released a new version of its Isaac robot development framework. Lots of new Lidar…
Monday
DIY Robocars via Twitter
RT @Smartphone89: DonkeyCar Racing League Korea #donkeycar @diyrobocars https://t.co/mDlHDR1d98
May 29
Jørn Ramnæs liked VIDEO LINK's profile
May 28
Mark Harrison left a comment on Moderators
"Wow, Ning2 looks really great on mobile. I had sort of drifted away as my browse-time went more on my phone, so this is great."
May 28
Hank Deucker left a comment on PIXHAWK
"I am sure most will say not again, Pixhawk telemetry. I do need help and all can be reassured that I have spent many hours scouring the net for useful information. I am not new at quadcopter flying, I started in 2012 and have progressed through many…"
May 28
DIY Robocars via Twitter
https://t.co/rLmFr8M2UK
May 28
DIY Drones via Twitter
Welcome to the new DIY Drones design!. You may have noticed that DIY Drones looks a little different today. That's… https://t.co/cg2EmeDGMQ
May 27
DIY Drones via Twitter
New! Online Training on Drones for Disaster Response https://t.co/brqRuujjY2
May 26
DIY Robocars via Twitter
https://t.co/8EMCvYW6oz
May 25
DIY Robocars via Twitter
RT @OttawaAVGroup: We are going to try something new this week. We will be having a drop-in style meeting Wednesday @ 7-9pm EST. Pop in and…
May 25
DIY Robocars via Twitter
RT @tawnkramer: Thanks Everyone for another fun virtual race! Amazing Ai racers competing head-to-head, Virtual Makers Fair event. Catch us…
May 23
DIY Robocars via Twitter
RT @make: Find out the latest from @diyrobocars at 10am PT from @chr1sa of @3DRobotics on Virtually Make Faire! #makerfaire #maketogether #…
May 23
DIY Robocars via Twitter
RT @Heavy02011: Join us Saturday online: Virtual Race League: @DIYRobocars Race #2 - Parking Lot Nerds https://t.co/aJUu4sdutx #Meetup via…
May 22
More…