Dr.Ben
Elite Veteran
Location: Richmond, VA, USA
| I throw this discussion out there for those pilots with some model helicopter flight control system experience.
If you closely study the way the control inputs to the lower head work, you can pretty readily see why the model veers as it does when you enter FF. Given a particular forward cyclic command, that input is present in the head not only with the blades perpendicular to the boom, but it also manifests as a right cyclic command when the blades are parallel to the boom. I'm sure the 45 d flybar offset has a role in how this whole system works, but it surely doesn't take an aeronautical engineer to understand why FF cyclic inputs in this model are mixed.
For those of the tinkering mindset, the next challenge would be to reconfigure the ties from the servos to the swash to "purify" the cyclic commands. Had I been designing this model, I MIGHT have thought about placing the motors at 90d orientation about the mainshaft, which would have then allowed the servos to also reside at a more typical 90 degree orientation as well.
Ben Minor |
