PID for large prop tricopter

[Tactical Ex]

I'm adjusting my Flip1.5 and I got all the gryos set the right way but its hard to fly. I'm overcorrecting and its flying all over the place but so far now yaw issues. My question is- with larger props, am I expected to need higher p and I gains or lower p and I gains ... In general. Also, I feel like it wants to drift backwards as if it considers level to have the tail rotor down a bit.

Also, stock p settings were 3.3 but without the min max range I have no idea if its high or low. 50 could be mid range for all I know. Anyone with a flip1.5 have to do extravagant tuning like me for a tri?

 

[RichB]

I'm adjusting my Flip1.5 and I got all the gryos set the right way but its hard to fly. I'm overcorrecting and its flying all over the place but so far now yaw issues. My question is- with larger props, am I expected to need higher p and I gains or lower p and I gains ... In general. Also, I feel like it wants to drift backwards as if it considers level to have the tail rotor down a bit.

Also, stock p settings were 3.3 but without the min max range I have no idea if its high or low. 50 could be mid range for all I know. Anyone with a flip1.5 have to do extravagant tuning like me for a tri?

With all other things being equal, larger props would probably require lower P values.

Maybe add some rc expo if it's too responsive.

For your autolevel drift issue:

Land and disarm. Move the throttle stick to full throttle. Move the pitch stick all the way forward while watching the controll board. It will flash about once per second. Let it flash 5 or so times before releasing the pitch stick. Move the throttle stick back to zero, re-arm and fly into a hover again. Rear drift will be less. Repeat as necessary, moving the pitch and roll stick in the direction that makes it closer to level. Each flash is a very small adjustment, so you may need a lot, but you can very finely tune your autolevel attitude this way.

 

[Tactical Ex]

I just tested it out. I know the "I" is too high now, I'm getting low frequency wobble. The "P" was way too low the first time. I moved it to 7 and its a bit high now and I'm expecting between 5 and 6 will be just right. As far as the pitch goes, I just added some trim and it works fine now.

Because the props are huge and spinning the same way, I cant turn left very fast because most of my yaw is spent staying centered but I guess I can deal with Zoolander syndrome if it at least works. I can get a different prop set later on for less than $10 anyways.

 

[RichB]

As far as the pitch goes, I just added some trim and it works fine now.

Your craft is confused about where level is. I provided instructions to teach it how to hover level. You have allowed it to remain confused but countered by telling it to lean slightly forward.

To each their own, but when you decide to graduate to rate mode, "lean forward" becomes "pitch forward" and your craft will constantly try to do a (slow) front flip until you remove that trim.

Because the props are huge and spinning the same way, I cant turn left very fast because most of my yaw is spent staying centered but I guess I can deal with Zoolander syndrome if it at least works. I can get a different prop set later on for less than $10 anyways.

Use a shim or some other method to slightly tilt your front rotors so that they are helping to counteract the prop torque. Your tail rotor can then sit closer to vertical, giving you more evenly-balanced maneuverability.

 

[Tactical Ex]

Your craft is confused about where level is. I provided instructions to teach it how to hover level. You have allowed it to remain confused but countered by telling it to lean slightly forward. To each their own, but when you decide to graduate to rate mode, "lean forward" becomes "pitch forward" and your craft will constantly try to do a (slow) front flip until you remove that trim.

I'm aware its not optimal, I'm going off of Luke Weakly's instructions from the maker tricopter guide which I read before your instructions. It's a very minor trim amount but I will keep what you mentioned in mind when I get the gains worked out and start fine tuning.

Use a shim or some other method to slightly tilt your front rotors so that they are helping to counteract the prop torque. Your tail rotor can then sit closer to vertical, giving you more evenly-balanced maneuverability.

I saw this mentioned elsewhere and think its a great idea (maybe it was you that mentioned it). I am using 10mm booms so I was thinking of cutting 2 strips off of a gift card. 1 will be 4mm and the other 2mm in width, both the length of the motor mount, glue them on the side of the boom (on top of each other) to raise the side up and hopefully give me some more yaw authority.

Thanks for the pointers