Variable Cam position with a Diff

[Wayne Blair]

Can you guys elaborate a bit.

I'm missing how you change the relative timing.

If I turn a the pinion of a 3.0:1 diff  at 300rpm the wheels will turn at
100 rpm. If i stop one wheel the other will speed up to 200 rpm.

I cant visualise the HW that will provide the phase shift between the 2 sun
gears of the diff. I'm assuming the cam is attached to one sun/spider (the
gear the axle usually messes in) gear and the cam drive on the the crown
wheel. The other spider gear is locked to the crown wheel to provide drive
constant drive? So are you providing limited relative movement betwen the
spare spider gear and the crown wheel ?

Have I just answered my own question ?
Maybe partly. 
How do ya control the relative movement on this thingy while it is spinning
around?

Is this how the planetry system would work too ?
Using a planetry of 2:1

if ya got the time


wayne