Movie 2.

Animations of the simulated mandible show how the equal distribution of elastic energy produces the same dynamics in a mandible closure with and without a pin joint. When the energy is partitioned unequally, the mandible translates as well as rotates, disrupting the circular kinematics. If this unequal partition of energy is constrained to have a frictionless pin joint, then the compressive spring oscillates during mandible closure, decelerating the mandible.

Dual spring force couples yield multifunctionality and ultrafast, precision rotation in tiny biomechanical systems

Gregory P. Sutton, Ryan St Pierre, Chi-Yun Kuo, Adam P. Summers, Sarah Bergbreiter, Suzanne Cox, and S. N. Patek

Journal of Experimental Biology 2022. 225:None-None; doi: 10.1242/jeb.244077