Input: pink crank.
Output: green rocker of straight groove.
Lengths of pink crank : a
Length of blue bar: 6a
Distances between stationary bearings: 1.5a + 3.5a
Blue line is locus of the yellow slider center.
In 1 rev. of the input, the output turns 180 deg. then stops.
Pause time corresponds more than 1/2 of working period.