Edible Soft Robots: Innovations in Biodegradable Robotics

Researchers at EPFL in Switzerland have developed a groundbreaking innovation in robotics: a 100% edible soft robot, including its battery. Traditionally, ingestible robots have posed safety concerns due to toxic components like motors and batteries.

However, this new robot features entirely edible parts, from its actuators to its energy storage system. The battery is made of gelatin and wax, utilizing a unique design that stores chemical energy in separate chambers of liquid citric acid and baking soda.

When pressure is applied, the membrane separating these substances ruptures, releasing CO2 gas, which powers the robot's movements. This battery operates in conjunction with an innovative valve that uses snap-buckling mechanics to open and close, allowing for controlled actuation.

The robot can perform about four bending cycles per minute for a couple of minutes before the battery depletes. The lead author, Bokeon Kwak, explains that one potential application is to administer nutrition or medication to elusive wildlife, such as wild boars, by mimicking their movement with the edible actuator.

This could allow for the targeted delivery of vaccines or other substances in a safe and biodegradable manner. The researchers emphasize that while the robot's taste is not its primary focus, the actuator has a sweet flavor due to glycerol, while the battery combines a crunchy exterior with a sour interior, reminiscent of lemon.

They have even experimented with flavored actuators, hinting at possible partnerships with candy manufacturers. Dario Floreano, the principal investigator, notes that this work not only advances edible robotics but also contributes to environmental sustainability by emphasizing biodegradable materials in robotic design.

The project is part of the EU-funded RoboFood initiative, and further developments may include edible elastic power sources for robots designed to leap off dessert plates. The research paper titled 'Edible Pneumatic Battery for Sustained and Repeated Robot Actuation' was published in Advanced Science, showcasing a significant advancement in the field of soft robotics.