Just like human swimmers, microswimmers have to coordinate their motion to swim. But unlike humans, swimmers like the freshwater alga Chlamydomonas reinhardtii doesn’t have a brain to help it synchronize its cilia. To investigate how these microswimmers manage their stroke, researchers built a biorobot with mechanically linked segments that mimic the alga’s swimming once a motor sets the robot vibrating.

When the robot’s base is allowed to rotate, the cilia synchronize in the freestyle-like R-mode. When allowed to move along an axis, the biorobot’s cilia synchronize in the X-mode, which resembles the breaststroke.

The researchers found two strokes that mirrored the real-life alga. In one, allowing the robot’s base to rotate produced a freestyle-like stroke they called R-mode. The other came from allowing the robot’s base to move forward and backward, which created a breaststroke-like X-mode. In the wild, only the X-mode provides helpful motion, but, oddly enough, the researchers found this mode was the most energy intensive. (Image credit: top – J. Larson, others – Y. Xia et al.; research credit: Y. Xia et al.; via APS Physics)

https://fyfluiddynamics.com/2024/09/synchronizing-cilia/

#biology #biorobotics #fluidDynamics #microswimmer #physics #science #synchronization