Skittles,
Training wheels - not a bad idea. Will minimise risk of dynamic rollover. Actually looking at some fixed wing gear would help. Some tail-dragger main gear designed for operation on rough strips hinges so that tyre contact patch moves radially about C of G (ie high roll centre suspension). The benefit is that cross-wind landings do not risk rolling the aircraft on landing.
Designing skids to flex about C of G will give the same advantage. Bug seems to have already considered this. I like the curve in the struts too, since this allows compliance in direction of C of G too (as well as a little plastic strain energy absorbtion
).
----
Bug,
If teetering: the control lead angle will be 90 degrees (less delta3 for coning, wee-wa, and/or inflow roll). Actually, i would seriously consider Dave Jackson's unihub design to minimise shaft vibrations, hence fatigue alternating loads, for your ring rotor.
If hingeless: you only need to know the first in plane bending mode frequency of the full disk. If this was checked in FEA with centrifugal accel applied then you can find control lead angle directly from my formula above. If you only know in plane bending frequency when static then a reasonable first estimate may be found using:
Freq-rotating < SQRT( Freq-static^2 + (RPM/60)^2 )
Where Freq-rotating then gets put into the equation for lead angle.
This approach works just as well for a ring-rotor as for individual blades because any fully teetering disk would remain in plane as you move the axis, in just the same way that individual blades do.Thus you can add centrifugal accel and bending hinge moments.
Assuming this hasn't totally befuddled you, i'd be happy to clarify a little more...