So I finished my Tarot 680Pro hexacopter build today, but had some reservations about one of the motors before takeoff. On the bench, I noticed that motor 3 (front left) was not spooling up like the others. Only when I ramped up to 1/4 throttle did I finally see movement from this motor, and even when I did, I doubted it was running at the same RPM's as the other motors.
Here's a link to what this looked like on the bench test:
https://www.youtube.com/watch?v=4ND7ewZ9Cew&feature=youtu.be
Thinking that maybe things would be different "in the real world" with my actual props installed, I gave it a go, but didn't get far. Same as before, I noticed that motor 3 was not spooling like the others and eventually tipped forward because of it:
https://www.youtube.com/watch?v=uam7JgyqXYo&feature=youtu.be
At this point, I'm at somewhat of a loss as to why this is happening. Being my first build, I'm hoping someone here can provide some tips on what to look for first. So far, I've checked my cabling, which appears to be fine. Not sure where to go with this next. Help?
Build Specs:
Pixhawk Flight Controller
SunnySky 4108S 380Kv Motors (x6)
Tarot 680Pro Carbon Frame
DX6i Transmitter
6S 6000mAh Turnigy Battery
Thanks in advance!
Erik
Replies
What have you done as far as ESC calibration? Have you tried swapping the motor leads at the ESC to see if the problem follows the motor or is ESC related? Have you tried swapping the ESC motor leads at the Pixhawk again to see if the problem follows the motor.
Can you provide any logs.
To be honest, I have not tried swapping the motor leads at the ESC or Pixhawk yet. I was going to try that first, but wanted to check with the experts first.
However, I have not done anything with ESC calibration yet. How would I go about doing that? These are the ESC's I picked up:
http://www.thanksbuyer.com/hobbywing-platinum-30a-pro-2-6s-speed-co...
Thanks again for your help,
Erik
Erik....come on....I gave you the link to the Wiki to answer you last question. As I said then, the Wiki is a great read. And....you really need to read it. I realize it takes time and you want to get this into the air. But in the time you spend trying things, scratching your head, and finally waiting here for answers, you could have already found the answer in the Wiki, 9 times out of 10. I'm not writing this to be mean but rather to help you get from A to B in the fastest and safest manner possible.
Good luck!
Greg, Stu,
Thank you both very much for your help. I spent quite a bit of time reading through the wiki, but somehow skipped over the ESC calibration step. To be honest, this project has been fairly overwhelming. Having next to no experience with multiroter aircraft, I've been watching youtube videos, reading through the wiki and various forums, etc. There's just so much information out there that it's easy to miss some of the basics like ESC calibration, which is a no-brainer to someone who has done this before, but a totally new concept to me.
I just re-read the entire "instruction" section of the wiki and verified that I had done everything on it (except for the ESC calibration). I went ahead and just performed the calibration, but had to refer to the chinese/english paperwork that came with my ESC's as the instructions on the wiki didn't work out for me. After reading both documents, I was able to figure out how to do the "all at once" throttle programming and I'm happy to report that I was successful with this. At this point in time, the copter spins up all 6 motors on my bench with consistency. Was very glad to see this as tearing the copter apart was low on my list of things I wanted to have to do after I put so much time and effort into it. :)
At this point, I'm going to attempt another maiden flight and I'm sure it will go well. Thanks again for your help in getting this noobie off the ground.
Regards,
Erik
Erik,
As they say, the devil is in the details. Glad to hear you got the ESCs calibrated....I'm sure your next attempt at flying will meet with much better results. I put my first quad together in November....so I understand your comment about the amount of information one needs to digest in order to be successful. That was my first R/C anything project and I've really enjoyed it so far.
Be sure to report back how the next flight goes and good luck!
Stu
Stu,
I'm happy to report that the test flight was successful! I did have a few surprises (rudder, pitch, and roll were reversed somehow), but I was able to bring it down safely and reverse those settings on my transmitter and had an easier time on round 2. I also learned a lot more about changing the various sensitivities, found a way to link channel 5 to enable alt-hold on demand, how to get data from the flight logs, etc. In all, I had 3 successful flights and continue to make improvements wherever possible. Next up, telemetry and GPS! :)
Thanks again so much for your help.
Erik
Erik....congrats! Way to go. Sounds like you are getting things going very well now. Yes, channel 5 is most handy for applying the various flight modes to the board. I have a batch (6 of them) programmed in the APM and my transmitter. I was out today doing some flying with a few friends. It was a good day....I didn't crash anything! :)
You'll enjoy the GPS modes when you get that configured.
Erik,
ESC calibration is the first step to solving your problem, also make sure your motors are turning the right direction and are in the correct numbering sequence for the PH.
You need to do a lot more reading!
Start with: http://copter.ardupilot.com/wiki/initial-setup/esc-motor/
Then read all of the "Instructions" here:
http://copter.ardupilot.com/