E. The Keyway Depth and Width
The keyway depth and height is shown in Fig. 4,
respectively, the keyway width u is represented as line
segment AB, and the depth v is represented as line segment
CD; namely, what we require is the length of line segment
AB and CD.
Search out all points having the same column number
and in the right edge, the keyway width actually is the
differences between the bottom point and the above point of
the maximal column number.
The keyway depth v can be determined by the length of
CO and OD. CO is the radius of the gear hub, can be
obtained by Least squares circle fitting [11]; the length of
line segment OD is the difference between the maximal
number of column and the abscissa of the center point O.
And then the keyway depth v is the sum of CO and OD.