Franz Reuleaux (French: [?œlo]; German: [?ø'lo?]; 30 September 1829 – 20 August 1905), was a mechanical engineer and a lecturer of the Berlin Royal Technical Academy, later appointed as the President of the Academy.
He was often called the father of kinematics.
He was a leader in his profession, contributing to many important domains of science and knowledge.
Today, he may be best remembered for the Reuleaux triangle, a curve of constant width that he helped develop as a useful mechanical form.