Ok, so I took the tri fo a spin today.
I ran it through 1.5 batts. It is still hungry for power at 22A for a hover, I've had to tune the pixhawk so that 70% throttle is the mid point. This is a bit of an issue as it means I've not got much reserve power. I think I need to redo the ESC calibration, I forgot to do that before I went up to fly, only remembered as I landed on the last go. Reason for this is that I'm still only using 28A at max throttle, if my bench tests are right I should get up to 39A at full throttle..... At 28A I'm only generating 600gx3=1.8kg, so lots of spare capacity - I want to access that as I had a fast descent and only just had the power to arrest it (got to only 20cms off the ground before climbing again). Flight time was around 10mins on the first battery, the 2nd one was around 6 mins but I only used 50% of the battery, the park was getting busier so I left.
Good news is the thicker wire means no floating to the ground at 50% battery capacity, I didn't reach that point but it was getting sluggish at about 80%.
I also think it would sing without the weight of the gimbal and camera, it's nearly 300g. My AUW with the gimbal is a shy under 1.5kg. I'm looking for weight savings at present.
Still to replace the FR4 radio mast with CF. I will try out the 4s 3000mah battery when it arrives, it could be tomorrow but more likely Wednesday. I do hope I don't have to change over to 4s batteries..... I have so many 3s batteries..... I dont think I could sling a 5000mah 3s under the mini quad.....
3 axis gimbal works ok, I think that's it's own level of tuning as I noticed in video that I've got some jello I didnt before, I think it was the gimbal motors introducing small oscillations. It's weird the settings I had for 2 axis were good but once you add the third in they are no good. I think I'll be playing with those settings for a while.
Main issues with the 3 axis gimbal was:
- Now have some jello due to incorrectly tuned controller
- As suspected you can confuse the yaw controller with fast yawing on the model
- If the yaw is not 100% straight with the model it is easily seen in the playback
I was able to correct the yaw issue by manually correcting in flight with a knob assigned to the yaw control. However you could get yourself into a position where you cannot fix it until you reach the ground. From reading I can resolve it by either upgrading to the 32bit version, using a 2nd 8 bit board or using a bigger yaw motor. Not sure what I'll do yet on that front. On a plus it did remove my tail wag that is common in tri's, particularly in gusty wind. I think some tuning will soften that out.
It was nice to fly forwards and have the camera pointed to the side, although this is easy to do in a multicopter without the yaw gimbal, just easier to do with the gimbal from a brain concept point of view.
Chris
