The team published the first iteration of this recipe in 2022. In their most recent work, published in Science Robotics, they added citric acid to keep microorganisms away and glycerol to keep the gelatinous mixture from drying out and becoming brittle. The material can be reused up to five times, and dissolves within hours when in water, compost or sewage.
Motion for the finger-shaped robot was controlled by compressed air, and integration of a light-sensing device enabled the robot to detect and move objects.
Interest in soft robots has been growing, particularly in applications such as surgery, but nonbiodegradable, oil-based materials are often used. The team will now attempt to make more complicated robots with more performance and functionality.