Re: next steps to optimizing multirotor setup
« Reply #15 on: January 03, 2019, 03:59:09 am »
Thanks guys I will have a look at those values not sure how that's happened... Will take a look at that file you supplied f5osh..

I'll have to have a play with the antenna, it's a bit of a pain the way the antenna is made up kinda difficult to get the wires to run out in a T like that... Or can I cut the heat shrink off if I have something to make it sturdy around the join ?

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Re: next steps to optimizing multirotor setup
« Reply #16 on: January 03, 2019, 07:07:53 am »
The problem with those antennas is that you really need to put the floppy wires inside a single tube so they remain vertical in flight.  That tube should be plastic.  Even with plastic, it can slightly detune the antenna depending on what kind of plastic it is.  It would be best to do range tests with and without, on the same day and as nearly as possible, the exact same environment.

Better yet to replace the top wire with stiff wire and the bottom wire with something more flexible.  This gets into the velocity factors of various metals and dielectric effects from the wire insulation affecting correct the wire length ... and/or hand tuning when done.

Or look here for some reviews on what I have tested.
https://forum.librepilot.org/index.php?topic=4199.msg28510;topicseen#msg28510

Re: next steps to optimizing multirotor setup
« Reply #17 on: January 03, 2019, 12:24:24 pm »
So I took this out today and had a good time.

Had green mag during heavy throttle inputs which is promising.. all ESC wiring is twisted / braided.

Tested position hold and velocityroam. Both worked well.

Position hold moves around a little bit... How steady does position hold hold the aircraft?

My board is mounted in free air out of the sun but not ideal in regards to the baro sensor. Not sure how kind of perturbations you get in the breeze ?

Another thing I haven't done is calibrated temperature drift ?

Position hold honestly wasn't that bad but I did notice that in velocityroam I was having random altitude drops.... It would drop about 4ft while moving side to side... It would recover altitude after... Not sure what to make of that.

My friend was with me with his phantom 4 pro so maybe I'm expecting a bit much :)
« Last Edit: January 03, 2019, 12:28:32 pm by glenneaux »

Re: next steps to optimizing multirotor setup
« Reply #18 on: January 04, 2019, 07:56:01 pm »
Position hold moves around a little bit... How steady does position hold hold the aircraft?
The longer you wait after power up and before takeoff, the more solidly the GPS will hold position.  It is a good idea to wait 12 minutes (almanac download) before the first flight of the day and 2 minutes or so for each new battery after that the same day.  Specs say that with correct warmup, it should usually be 1-2m very slow drift; not really noticeable except if you PH for a long time.  VR with neutral sticks is exactly PH.

My board is mounted in free air out of the sun but not ideal in regards to the baro sensor. Not sure how kind of perturbations you get in the breeze ?
Prop blast will hit the baro sensor.  Try hard yaw, hard roll bank, hard pitch bank and you may see more effect in some cases than others.  This is a thing that I have a hard time correcting sometimes.  On a quad with the FC on top I put the FC in a loosely sealed dome (clear food container).  On a quad with FC between two body plates I had to seal the edge all the way around.

Another thing I haven't done is calibrated temperature drift ?
Thermal calibration helps.  Without it, you will see a slow change in altitude of as much as 4 meters over the course of a flight as the FC warms up.

Position hold honestly wasn't that bad but I did notice that in velocityroam I was having random altitude drops.... It would drop about 4ft while moving side to side... It would recover altitude after... Not sure what to make of that.
Baro is sensitive to light.  It needs to be hidden from light.  Black, open cell foam helps for light (and somewhat for prop blast too).  This post has a picture of black open cell foam:
https://forum.librepilot.org/index.php?topic=1284.msg9388#msg9388

and wiki has pictures
https://librepilot.atlassian.net/wiki/spaces/LPDOC/pages/12058671/Altitude+Hold
« Last Edit: January 04, 2019, 08:43:22 pm by TheOtherCliff »

Re: next steps to optimizing multirotor setup
« Reply #19 on: January 17, 2019, 01:06:39 pm »
Hi guys

Still haven't covered my baro but had good flights today flying fpv

This was flying mostly attitude mode but also happily using velocityroam and position hold.


Cliff changed the links to point to youtube.com instead of youtu.be so they would be visible in the forum






My OSD isn't working at all, kvteam minimosd.. have had it working but never without problems... Have had video resets, currently only getting flickering osd data on the sides... Not sure what to do I am tempted to turf it all and start again
« Last Edit: January 18, 2019, 12:59:03 am by TheOtherCliff »

Re: next steps to optimizing multirotor setup
« Reply #20 on: January 18, 2019, 05:10:24 pm »
Similar problems with my OSD; mainly just resetting over and over but only in flight.  Tried several noise filters on 5V and 12V, and it didn't help.  It turned out to be that it didn't like 12V straight from the battery because of less than 12V and fluctuations.  Right now I have mine disconnected, but I think that an up/down regulator (so it can make 12.0V from 12.6V or 10.5V) would fix it.
« Last Edit: January 29, 2019, 12:09:39 am by TheOtherCliff »

Re: next steps to optimizing multirotor setup
« Reply #21 on: January 28, 2019, 02:39:52 pm »
Similar problems with my OSD; mainly just resetting over and over but only in flight.  Tried several noise filters on 5V and 12V, and it didn't help.  It turned out to be that it didn't like 12V straight from the battery because of less than 12V and fluctuations.  Right now I have mine disconnected, but I think that an up/down regulator (so it can make 12.0V from 12.6V or 10.5V) would fix it.

I'm about to embark on fixing up my OSD.....

Do I buy something else or get this one sorted.

I've got a micro minimosd, and it's powered by 5v from the FC per librepilot doc.... I use the USB com bridge to program it.

Somethings I considered were bad 5v and bad earth arrangements...

The ground goes straight to the FC which grounds via the bec in one of the four ESCs

The 5V is the same source as the FC.

I am going to bench test with / without the camera and vtx to try and confirm everything else is ok.


I currently have video passing through the OSD but no OSD at all. Last time I flew I had a video reset but only once.

Tonight I disconnected my camera and still had no OSD which was strange...

I then tried to talk to the OSD with its config software and still nothing.

Do I pursue this minimosd or do I buy a full size minimosd that comes in a case which will solve another problem...