Mikrokopter GPS Question

[Photo Elevate]

Just finished building Mikrokopter octocopter.

Could anyone advise if it is good or bad practise to take off or land in GPS mode.

Many thanks

Dave

 

[Carapau]

In general, lifting off in GPS mode is not a problem. The key to a good safe take off is not to fanny around by trying a slow gentle take off, instead just get the aircraft off the ground by giving it the beans. The reason for this is that should there be any lateral drift on take off then a slow take off could mean that your skids will catch on something causing a tip over. This can happen in any flight mode by the way, not just GPS. I take off in GPS when ever I can and have never had an issue. I don't fly MK by the way but principles should be the same.

 

[cootertwo]

From what I've read, "IF" you are in an open area, and have 6 or more satellites "locked in", taking off in GPS should be no problem. Problem happens when not enough sats, or, on and off sats can confuse the MC, and make it think it was moved around after the initial warm up and GPS lock. It then trys to scoot to that other location as soon as it gets light on it's feet, usually sliding one way or the other, and falling over on it's side.

 

[Carapau]

It then trys to scoot to that other location as soon as it gets light on it's feet, usually sliding one way or the other, and falling over on it's side.

Which is another reason to give it the beans on take off.

 

[PMaughan]

I got rather shot down for this in another thread but I think it's best to take off in Atti or similar non GPS reliant mode. I only think this because it's in the Wookong manual and I do love a manual! It also makes sense to me. But either way as Carapau says give it a good bit of welly to get it in the air.

 

[mephisto]

Absolute bad practice - no matter what FC you are using. The reason is easy:

The lower your Kopter is in the air, the less it sees the Sat's which are near the Horizon, and they have most Influrence on the lat/long Value. This may result in Position jumps that may lead to unexpected Position changes - and accidents.

 

[Bartman]

....The lower your Kopter is in the air, the less it sees the Sat's which are near the Horizon, and they have most Influrence on the lat/long Value.....

very interesting, I didn't know that!

 

[stevemaller]

I never take off with GPS Position Hold enabled. The reason is simple: it's quite difficult to correct for a GPS glitch whilst applying power to lift off. My practice 100% of the time is to take off in Manual mode, climb to 3-4 meters, enable Altitude Hold, observe stability, enable Position Hold, observe stability, then usually disable both AH/PH and do my flying. I personally usually use PH only when "parking" to do stationary shots or pans. MK's overall stability on my heavy lift X8 copter in manual mode is very stable, and I do not care for the flight characteristics in "dynamic position hold". It's just not worth the risk of having a GPS glitch in flight. And it does happen. It's far easier to correct a problem if the copter's in a hover.