I am having issues between the behavior of my Hexacopter with pixhawk when I fly at Dusk and when I fly in morning with sunlight. At dusk the altitude is not bad in Atl Hold and Loiter. During the day time the alt hold is very poor 2-3 meter variations within 15-20 seconds.
I have a feeling its either temp or maybe sunlight dependent.
Link to bin files
4-15 was a dusk flight to test battery life. I set it to fly at 2 meters seemed to do so without too much issues
4-16 is the next morning. I made multiple flights over 1.5 hours changing psc_accz_I and P and thst_expo and what not. didnt seem to help. around 10:42 it was getting crazy
Hope it helps. Be sure to cover with a dark-black foam (not pink or other light color). I found that a lot of packaging foam from electronics works well. Just cover the barometer (has a hole) and make sure you can blow air through whatever kind of foam you use. It made a difference on my builds to both light and propwash affecting the machine.
I ordered some black open cell foam. Should be delivered tomorrow and I can add the foam. I looked at you link and others and it seems to be the cure. I hope so.
This hexa was supposed to be a relaxing inexpensive build so I can get familiar with qground control for work, but it’s quite a learning curve. Without this forum I would have replaced the Pixhawk with something from mRo.
That’s right. They both use the Altitude Hold Controller. Right out of the Loiter Wiki: Loiter mode incorporates the altitude controller from AltHold mode. Details for tuning AltHold are on this wiki page
I opened the pixhawk and there was no foam in the little well. I put some open cell foam black in the well and added some black electrical tape to the inside the pixhawk case to help keep light out. Won’t have a chance to test till Friday or this weekend. Will report results.
Would like to report a successful test of the foam covering the Baro. Did a short test (two 1 mint flights back to back) at 10:30 AM in full sunllight with no altitude holding issues in alt hold, loiter and RTL.
Very thankful for your advice and am gaining confidence with this hexa.
Very stable altitude holding. easy less than 1 ft max and with in 6 inches most of the time in loiter.