MultiWii

Hello guys,

This is my first Multicopter and I've been trying to lift up my quad for a few days now, but for some reason I can't get full throttle with my 4 turnigy 750kv motors.

Today I wiped the Eeprom and uploaded the new Multiwii 2.3. Then I was testing the board to see the throttle motors reaction and it seems that there's something wrong.

I recorded a video to show you what is happenning. Nothing is connected to the board besides the receiver.

Here's the video:
https://www.youtube.com/watch?v=hah0Vh1GksY

What am I doing wrong? The throttle of each motor should increase equal shouldn't it?

Best regards

Edited:
Ok, I just read in another post that what's happenning is normal because the quad isn't in the air and it's trying to correct itself.

Are the motors connected to your bord & spinning?

They shouldn't, because if I see that correctly, you haven't calibrated your ACC yet (click CALIBRATE_ACC and hold bord still for 10 seconds). I think there is some influence of the sensors on your throttle signal, so these are some possible issues to search for:
-You have selected the wrong board and/or the wrong sensors. Thus, your bord is trying to compensate with faulty signals and this cannot work.
-You haven't calibrated anything. This would eventually lead to your motors not starting at all. Thats why I asked what exactly is connected to your bord. In fact, you shouldn't even be able to arm it.
-Your bord is defective (I don't think thats the case).

I would suggest to check your config.h or use a clean MultiWii version. Make sure to clear all 4096 bytes with the clear_eeprom sketch (change the 512 in the sample sketch to 4096), upload the clean version with a correct config.h (correct bord and correct sensors), calibrate the ACC and then try again.
My guess is, as said, that some of your sensors are trying to compensate movement that is not there, which will lead to inequality regarding the throttle signals.

If that doesn't work I'm interested in a picture of your wiring.

Nerox wrote:Are the motors connected to your bord & spinning?

They shouldn't, because if I see that correctly, you haven't calibrated your ACC yet (click CALIBRATE_ACC and hold bord still for 10 seconds). I think there is some influence of the sensors on your throttle signal, so these are some possible issues to search for:
-You have selected the wrong board and/or the wrong sensors. Thus, your bord is trying to compensate with faulty signals and this cannot work.
-You haven't calibrated anything. This would eventually lead to your motors not starting at all. Thats why I asked what exactly is connected to your bord. In fact, you shouldn't even be able to arm it.
-Your bord is defective (I don't think thats the case).

I would suggest to check your config.h or use a clean MultiWii version. Make sure to clear all 4096 bytes with the clear_eeprom sketch (change the 512 in the sample sketch to 4096), upload the clean version with a correct config.h (correct bord and correct sensors), calibrate the ACC and then try again.
My guess is, as said, that some of your sensors are trying to compensate movement that is not there, which will lead to inequality regarding the throttle signals.

If that doesn't work I'm interested in a picture of your wiring.

I'm using the HobbyKing Multiwii 328p Flight Controller: http://www.hobbyking.com/hobbyking/stor ... _port.html

And actually I could arm the motors before uploading the multiwii 2.3 code to the board (I haven't tried it again after upgrading). I've already calibrated all ESC's and they are all starting at the same time when armed. When I raise the throttle putting the throttle stick to mid, everything works fine, motors accelerate equal and fine, but from mid to full throttle nothing happens, so it won't lift up.

I recorded a video in my room, then you can see what's happening. Before you ask about my battery because it looks big and heavy, i'm using a turnigy 3s2p 3400mAh LiFe Pack: http://www.hobbyking.com/hobbyking/stor ... duct=16588

Video: https://www.youtube.com/watch?v=UOCw9AfILc4

I just lost track of what you did so...have you tried turning it on and off again?

Joke apart. You were able to start your motors without flashing ANYTHING on the board?
I would suggest that you do the following:
UNMOUNT your props
As you said, your ESCs are already calibrated
Clear every 4096 bytes of the EEPROM
Download a CLEAN MultiWii 2.3 version (maybe also the Nav b.7 version) and ONLY set your Copter type (QuadX) and your board. Minthrottle should be okay, maybe change it according to your ESCs.
Calibrate ACC
And then check how your motors react to throttle.

Well your original video shows that you haven't adjusted your tx endpoints and midpoints, and it obviously doesn't have the props on in that video in which case the FC can't adjust the position of the copter and the motors will vary as it tries. Those readings only really help when the craft is in the air.

Also there a quite a few posts right here with people asking the same exact question and many helpful responses from other people...maybe try a search before posting.


Mike

Nerox wrote:I just lost track of what you did so...have you tried turning it on and off again?

Joke apart. You were able to start your motors without flashing ANYTHING on the board?
I would suggest that you do the following:
UNMOUNT your props
As you said, your ESCs are already calibrated
Clear every 4096 bytes of the EEPROM
Download a CLEAN MultiWii 2.3 version (maybe also the Nav b.7 version) and ONLY set your Copter type (QuadX) and your board. Minthrottle should be okay, maybe change it according to your ESCs.
Calibrate ACC
And then check how your motors react to throttle.

I've done what you said and it seemed that the motors were reacting quite better (or correctly) to throttle (without anything connected besides USB and Rx). So I mounted everything and ran outside to see if it could lift up, but sadly it didn't. I armed the 4 motors at the same time, everything looks calibrated and good to fly, but I just can't have enough throttle to lift, it seems that when the quad is about to lift, the throttle becomes insane and goes up and down by it self. Actually it "jumped" a little bit, but that's all.

I was wondering, maybe I should change de PID settings of the board? I've read somewhere that vibrations can cause this kind of problem (i've already tried to isolate the vibrations of the quad to the board), but I don't think this is my case.

What do you think? Do you want me to upload another video?

mike105105 wrote:Well your original video shows that you haven't adjusted your tx endpoints and midpoints, and it obviously doesn't have the props on in that video in which case the FC can't adjust the position of the copter and the motors will vary as it tries. Those readings only really help when the craft is in the air.

Also there a quite a few posts right here with people asking the same exact question and many helpful responses from other people...maybe try a search before posting.


Mike

Mike, thanks for your answer.

I adjusted the midpoints now, all values are 1500 (+-5). I updated my post because as you said there are a few posts asking the same question and I realized it right after posting this , I'm sorry for that.

Anyway i'm facing a new problem now, I wish I could change my post title but this is not possible...