Hey folks,
Just started out in the world of quads and built my first. Basic components x450 + nanoWii + Qbrain ESC. My question is, why would I want to use a barometric sensor? To allow the quad to hover in a specific spot? If I used one, what has to be setup in MWC? Also, is there any calibration that has to be done once setup? Thx.
Quad Noob Question - Barometric sensor
Re: Quad Noob Question - Barometric sensor
Hi !
The Barometric sensor (aka BARO) helps to use the ALtitude Hold mode.
You can flick a switch on your Tx ant the craft holds altitude.
There are 2 obstacles to overcome:
-1-The sensors are typically sensitive to light (strange, isnt it) and to local pressure changes (wind gusts, prop backwash, ...). So many guides include to put a sort of black foam over the deciding parts of the Baro. Please do that, its pretty dangerous to use otherwise.
Look here:
http://www.rcgroups.com/forums/showpost.php?p=27054388&postcount=1069
Guide is for APM but its the same problem really...
-2- On MultiWii (not on APM) the ALT Hold needs serious PID tuning to work good.
So when first trying it, climb to a good altidute before you "flick the switch" and if the copter goes haywire flick back FAST and put your throttle in hover / middle position !!!!
There are only poor guides on ALT HOLD tuning (if you find a good one, may post it here) and the math behind seems not very good or stable.
But some heroic people get it to +-20cm which is great, so its in there, we just have to get there...somehow...
Greetings,
Ender
The Barometric sensor (aka BARO) helps to use the ALtitude Hold mode.
You can flick a switch on your Tx ant the craft holds altitude.
There are 2 obstacles to overcome:
-1-The sensors are typically sensitive to light (strange, isnt it) and to local pressure changes (wind gusts, prop backwash, ...). So many guides include to put a sort of black foam over the deciding parts of the Baro. Please do that, its pretty dangerous to use otherwise.
Look here:
http://www.rcgroups.com/forums/showpost.php?p=27054388&postcount=1069
Guide is for APM but its the same problem really...
-2- On MultiWii (not on APM) the ALT Hold needs serious PID tuning to work good.
So when first trying it, climb to a good altidute before you "flick the switch" and if the copter goes haywire flick back FAST and put your throttle in hover / middle position !!!!
There are only poor guides on ALT HOLD tuning (if you find a good one, may post it here) and the math behind seems not very good or stable.
But some heroic people get it to +-20cm which is great, so its in there, we just have to get there...somehow...
Greetings,
Ender
Last edited by enderffx on Fri Feb 28, 2014 2:27 pm, edited 1 time in total.
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deejayspinz
- Posts: 23
- Joined: Thu Feb 20, 2014 12:01 pm
Re: Quad Noob Question - Barometric sensor
Thanks for the good tips.
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deejayspinz
- Posts: 23
- Joined: Thu Feb 20, 2014 12:01 pm
Re: Quad Noob Question - Barometric sensor
A follow-up question. I have a barometric sensor on order from DX. Can someone clarify the steps I need to go through to enable it and get it working?
I have MWC 2.2 installed and will install the sensor when I get it. Once this is done, what lines need to be un-commented on in the sketch to enable the feature? What about the gui - do I need to re-run it and re-calibrate something? Change a setting?
Thx
I have MWC 2.2 installed and will install the sensor when I get it. Once this is done, what lines need to be un-commented on in the sketch to enable the feature? What about the gui - do I need to re-run it and re-calibrate something? Change a setting?
Thx