If you look close, you can see the top of the ball at the base of the rotor shaft.
Here you can see that Bob has used a mechanical mixer attached to the ball for dual (dc) control.
This model flew at the Martinsville fly-in (Gyronuts `98)... It has experienced some apparent and unexpected drag somewhere in the ball socket system... and the subsequent control problems has cost
Bob a servo and Receiver ... This idea had a lot of merit to it, and was well worth the experiment. The rigging
of the ball created an automatic (slight) up vector in turns, which could be considered very good for most models. Very nice work Bob!
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