Input: one of two yellow bars that turns on stationary bearings.
Violet bar draws two perpendicular straight lines (in blue and green).
The green intersects axes of three stationary bearings.
The blue is perpendicular to the green at its intersection with the axis of the middle bearing.
Length of yellow bars: a.sqrt(2)
Length of blue bars: a
Length of pink bar: 2a
Length of violet bar: a.sqrt(2) + a.sqrt(2)
Horizontal distances between three stationary bearings: a
If the input turns 360 deg as shown in this
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