Protruding Eyes, Mouth Make Stingrays More Hydrodynamically Efficient

In Physics of Fluids, researchers detail how the protruding eyes and mouths on simulated stingrays affect a range of forces involved in propulsion, such as pressure and vorticity. They created a computer model of a self-propelled flexible plate that mimicked a stingray’s up-and-down harmonic oscillations and used it to illustrate the complex interplay between hydrodynamic forces. The group found that the eyes and mouth help streamline stingrays even further.

Batteryless Pacemaker Could Use Heart’s Energy for Power

The cardiac pacemaker of the future could be powered by the heart itself, according to researchers in China. Current cardiac pacemakers use a battery power supply and leads to keep hearts beating regularly. Yi Zhiran and his group are investing batteryless powering and leadless pacing, harvesting kinetic energy from the heart to power the lifesaving device. The energy is harvested by the buckling of the encapsulated structure of the pacemaker, creating buckled piezoelectric energy.