Four bars linked with four parts of connection, 2 sationary.  By driving line ab to rotate around point a “a rathering intriguing motion” occurs.
Designed by john bryant and chris sangwin (how round is your circle”)

Analysis:

The four bars were recreated however the proper angles could not be determined.  The outcome was a rotating parallelagram.

Execution:

A parametric circle was added to this mechanism.  The diameter of the circle chages with the rotation on point e.

Grasshopper Definitions:

Iteration 1:

Iteration 2:

Iteration 3:

Iteration 4:

Iteration 5: