MultiWii Pro Arming Issues

[alexjblake]

Hello everyone,

Firsty a thanks to all the information that I have read by everyone who's posted on here...you've kept me from throwing a lot of things around.

However, I'm having huge issues getting my Quadcopter to arm!

My current setup is:

Multiwii Pro Board - Running MultiWii 2.3
QBrain 20A ESC - Calibrated
Flysky fs9 th9x & reciever
4 x 900kv motors

So I've got everything connected up with all the right pins connected up and showing up as results in WinGUI. Ranges from around 970 to 1980 on the flight data boxes. I've been trying to arm it by having throttle all the way down and either pushing the yaw or roll to the right to arm and left to disarm. On the MultiWii Pro itself an LED changes from nothing to bright red when arming and back to off when disarming but in the GUI there is no change in the ARM box, so I know something is happening but I don't get any motor output! Frustrating!

I've uploaded my ardunio config here : https://www.dropbox.com/sh/9gtnwnpu6z695uy/AABCzmAABnZ9iEsE2ULTG0pSa

And attached some photos :

This is the GUI Screen when trying to arm
https://www.dropbox.com/s/kimhd7yp2z8ijri/Screenshot 2014-08-14 21.04.58.png

This is the GUI Screen when trying to disarm
https://www.dropbox.com/s/lo2auaighv7om1i/Screenshot 2014-08-14 21.06.29.png

This is the LED on when 'armed'
https://www.dropbox.com/s/lo2auaighv7om1i/Screenshot 2014-08-14 21.06.29.png

This is the LED off when 'Disarmed'
https://www.dropbox.com/s/1upb812j4q67tkn/2014-08-14 21.07.00.jpg

I will be so grateful to anyone who can come up with a solution to this it's driving me crazy (I'm new to the quadcopter game) and slowly I'm losing faith!

There's a beer or a giftcard up as a token of goodwill to the person who can solve my problem!

Alex

 

[Snarls]

Hi Alex, I had this same problem when I was trying to arm my Multiwii Pro for the first time. Here's what I did to fix my problem. In the Arduino sketch for your version of Multiwii there is a piece of code in the config.h tab just below where you define your type of aircraft. It should look like this:

There could either be two problems when arming; first the quad is armed but the motors aren't receiver enough of a signal to spin up, or second the TX is not sending a value that the Multiwii recognizes as "arm."
It's been awhile since I solved this problem but I remember that I changed the values of MinThrottle and MinCommand. MinCommand is the value multiwii wants to arm and is 1000 at default. From your pictures your yaw only reaches a low point of 1006 which is above the 1000 limit. So first I would try either changing your TX endpoints to get values below 1000 or change the value in config.h to something above 1006.
I also changed MinThrottle. This is the minimum value your ESC needs to send to the motors for them to spin. What you can do is power one or all of your motors and see what TX value the motor starts spinning at. In my case I lowered the value of MinTrottle from 1150 to 1064.

Once again it's been awhile since I did this so I'm not 100% that is exactly what solved your problem. If nothing works then you could always arm using a switch on the TX. This is what I do, but I will try arming with the sticks and get back to you. Hope this helps.

 

[Craftydan]

Alex,

First off, welcome to the forum!

Are you doing all this with the board only powered from the USB? I've had issues in past with mine where it refuses to truly arm if the battery is not plugged in -- I don't see in schematics or code how it could distinguish, but it's a behavior I've noticed in past.

A few other things that might be stopping you:

- have you calibrated the Acc?
- looks like the baro light is off, are you sure the mode is disabled? (it will prevent arming)
- have you tried this in the old multiwii configurator? on 2.3 neither are flawlessly performing -- but the indicators on the old utility seem to work fine on 2.3 even if things are a little misplaced on the screen.

 

[alexjblake]

Alex,

First off, welcome to the forum!

Are you doing all this with the board only powered from the USB? I've had issues in past with mine where it refuses to truly arm if the battery is not plugged in -- I don't see in schematics or code how it could distinguish, but it's a behavior I've noticed in past.

A few other things that might be stopping you:

- have you calibrated the Acc?
- looks like the baro light is off, are you sure the mode is disabled? (it will prevent arming)
- have you tried this in the old multiwii configurator? on 2.3 neither are flawlessly performing -- but the indicators on the old utility seem to work fine on 2.3 even if things are a little misplaced on the screen.

I've calibrated the ACC on a level surface but it fluctuates around a bit
I seem to have managed to assigned the Arming to an AUX switch on the remote, which I guess for now is okay but a new issue has arisen with the motor speeds.

It appears that the motors don't throttle at the same rate? I've calibrated the QBrain with the hub and tried the ESC_CALIB_CANNOT_FLY but it still persists?

https://www.youtube.com/watch?v=OWAgmmhZ5VQ&list=UUtCUb6W5b9yxkQb4Wk7tUIQ

 

[Craftydan]

Ok, you've armed and the motors are responding . . . good!

Yeah, you're looking at the slight variation between ESCs -- only so much you can do with this. Because the board isn't flying the craft yet, it isn't maintaining correction between the motors to keep the thrust constant . . .

. . . but the mere fact you can command one to be "on" with another "off" can be trouble in a strong descending maneuver, since the board might slow an ESC below it's "off" when it merely wants to idle it.

Go into the config.h and bump up the "#define MINTHROTTLE" value, test, and repeat until all 4 start at the same time.

This is the lowest "ON" throttle setting the control board will send to the ESCs, so they better all be on a tthe same time or it won't end pretty.

 

[alexjblake]

Ok, you've armed and the motors are responding . . . good!

Yeah, you're looking at the slight variation between ESCs -- only so much you can do with this. Because the board isn't flying the craft yet, it isn't maintaining correction between the motors to keep the thrust constant . . .

. . . but the mere fact you can command one to be "on" with another "off" can be trouble in a strong descending maneuver, since the board might slow an ESC below it's "off" when it merely wants to idle it.

Go into the config.h and bump up the "#define MINTHROTTLE" value, test, and repeat until all 4 start at the same time.

This is the lowest "ON" throttle setting the control board will send to the ESCs, so they better all be on a tthe same time or it won't end pretty.

CraftDan,

Thanks for that advice, I think that has helped it. I'm just going through a bunch of different settings going up in around 20unit intervals. I'm just waiting on some CW and CCW blades to try out some real flying!

Cheers,
Alex

 

[thenated0g]

couple times i have been super pumped up after a crash and forgot to turn my dual rates off. You cant arm with dual rates at certain settings.