On adjustable spherical four-bar motion generation for expanded prescribed positions

This work formulates and demonstrates a method to synthesize two-phase adjustable spherical four-bar mechanisms to approximate substantially more prescribed rigid-body positions than with conventional motion generation methods [C.H. Suh, C.W. Radcliffe, Kinematics and Mechanism Design, John Wiley and Sons, New York, 1978]. An alternate set of mechanism constraint equations are formulated using the Method of Least Squares and solved for the adjustable spherical mechanism moving pivot variables. The example included demonstrates the synthesis of an adjustable spherical four-bar mechanism to approximate twice the number of prescribed rigid-body positions per phase than with a conventional method [C.H. Suh, C.W. Radcliffe, Kinematics and Mechanism Design, John Wiley and Sons, New York, 1978].