Compliant Mechanisms that Roll Like GEARS!! -- #VeritasiumContest

#VeritasiumContest I am posting this video in response to a contest announced by Veritasium challenging educators to explain a counter intuitive concept in one minute or less (). Since the prize money is coming from a UCLA professor who lost a physics bet to Derek from Veritasium, this is my attempt as a fellow UCLA professor to redeem my university’s reputation. This video is about how compliant rolling-contact joints can be used to counter intuitively create compliant lattices of gears. Compliant rolling-contact joints consist of crisscrossing flexures that are deformed around cams. They achieve large ranges of deformation without increasing in stress and achieve near zero stiffness about the desired axis of rotation while maintaining high stiffness in all other directions. 2D and 3D lattices of many shapes can be designed. My work pertaining to these lattices, which are called ‘Compliant Rolling-contact Architected Materials’ (i.e., CRAMs), is previously published