## **Moving soft robotic fingers made from plant-based materials** Researchers at the Seoul National University develop stretchable and soft **robotic** fingers that **decompose** in soil over time and act as a natural fertilizer. The body of the robotic fingers is built from polyglycerol sebacate, a synthetic elastomer made from glycerol and sebacic acid. Glycerol is a byproduct of biodiesel production while sebacic acid is derived from castor oil, and both of them are **plant-based**. Polyglycerol sebacate is safe since it is already used in medical implants because the body can absorb it without a toxic response. Typical sensors and active elements of the electronic components are made of silicon, molybdenum, and magnesium, which are inorganic materials found in every smartphone and circuit board currently filling landfill sites. For the soft robotic fingers, the researchers used a class of electronics called transient inorganics, or components that are engineered to dissolve in specific conditions.…