Researchers have been inspired by geckos' feet to develop a liquid crystalline elastomer material that bends in set directions in response to heat and light.
Nature is inspiring the design of more efficient solar harnessing technology. We’ve seen designs inspired by insects eyes and butterfly wings. Now, researchers have turned to geckos for inspiration. Geckos’ feet are covered with microscopic hairs or setae which allow them to easily grip walls and structures.
Researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering have tried to replicate such microstructures using a liquid crystalline elastomer (LCE) material that can bend towards light. LCEs are chains of molecules with elastic properties. When LCEs are heated, they lose their initial shape and relax to form new shapes. Once the temperature drops back to normal, the LCE returns to its original set shape.
However, LCEs have a limited range of movement. The researchers at Harvard developed a method that overcomes this limitation. They found that by applying magnetic forces during the making of the LCEs, they could set the original LCE shapes based on the orientation of the magnetic fields. Therefore, the team were able to finely control how the LCEs would change in response to temperature and, crucially, light. They used this method to develop 3D structures that autonomously bend towards a moving light source, so that solar panels could act like sunflowers following the sun.
LCEs could also act as an adhesive, sticking in one form and releasing during another. Additionally, LCEs could be used as ‘muscles’ in soft robotics, expanding and contracting for movement.