For some time we have experienced intermittent porpoising (pitch oscillations) on our aircraft when transitioning from VTOL to fixed wing flight. Sometimes it will do it real bad (high amplitude), others not at all. Some things that seem to affect it include stiffness of the tail’s mounting (A-tail supported by the vtol booms), and stiffness of the fuselage to wing mount. Any slop in either of those seems to make the porpoise way worse. I notice that both the VTOL and plane controls are fighting to correct this and wonder if this has something to do with this, but I have a feeling the root is in poor plane pitch PIDs.
Has anyone else had this problem?
Can someone look at this log and tell me how you’d adjust the PIDs (specific attention to time 15:50:43) I am in need of someone who is good at PID analysis and am willing to pay for good help and instruction. Autotuning isn’t really an option.