For anyone interested there is a 748 page atlas of available curves, mechanically generated and published in 1951. It's out of print but there are pdfs on vario

For anyone interested there is a 748 page atlas of available curves, mechanically generated and published in 1951. It's out of print but there are pdfs on various sites. The pages look like this: https://www.gutenberg.org/files/27106/27106-h/images/fig-45.jpg https://www.gutenberg.org/files/27106/27106-h/images/fig-45.... Analysis of the Four-Bar Linkage Its Application to the Synthesis of Mechanisms by John A. Hrones and George L. Nelson Hardcover ISBN: 9780262080033 Published: June 15, 1951 Today the pages can be software generated: https://www.cedarville.edu/cf/engineering/kinematics/ccapdf/fccca.htm https://www.cedarville.edu/cf/engineering/kinematics/ccapdf/... https://demonstrations.wolfram.com/CouplerCurveAtlasForTheFourBarLinkage/ https://demonstrations.wolfram.com/CouplerCurveAtlasForTheFo... The purpose was to allow engineers to design (on paper) mechanisms where a motor could drive a crank link connected to a rocker link via a coupler link (think of it as a plane being moved) and a certain point on the coupler could describe a complex curved or straight path. You figured out roughly the path you wanted and went looking for it in the atlas. Each atlas page had varying integer combinations of linkage lengths and the coupler link had 5 to 7 curves traced out for different points on it.