EPFL: On the way to the edible robot
Edible robots sound unnecessary. But there are good reasons for this. Researchers at EPFL have produced a paper that describes the challenges.
The rolling robot from EPFL and IIT includes parts that can be eaten.
(Image: EPFL)
There can be many reasons for fully edible robots, say researchers at the École polytechnique fédérale de Lausanne (EPFL). They want to develop and build such robots so that they can be used in medicine, for example. However, before a robot can be fully consumed and digested, the scientists still face a number of challenges, which they outline in a scientific perspective article.
Robots are not normally there to be eaten. When they are no longer needed, they are scrapped. However, in times of diminishing resource availability, the use of organic and biodegradable materials is worth considering reducing e-waste if robots are made from edible, i.e. biodegradable, materials. They could also be used to supply people in disaster areas in emergencies, for example with edible drones. In medicine, edible robots could transport medicines to the right places in the body without having to remove them from the body. Human digestion does this fully automatically. Last but not least, edible robots could also pave the way for new culinary experiences.
In the scientific paper "Towards edible robots and robotic food ", published in Nature Review Materials, EPFL scientists have investigated how far research is still away from fully edible robots and the challenges that lie ahead. In it, they describe which edible materials can be used for robot construction and behave similarly to non-edible materials.
Edible materials for robot construction
For example, gelatine can replace rubber and rice cookies are similar to foam. A chocolate film can protect robots in humid environments, for example. Adhesives can be imitated from a mixture of starch and tannin, the scientists write. It is difficult to build completely edible electronics that include transistors and other electronic components. The greatest challenge is to connect components that work with electricity, such as batteries and sensors, with components that are operated with liquids and pressure, such as actuators. In addition, the individual components must be miniaturized and the durability of the edible parts must be increased so that they can be used in medical applications, for example. The robots also need to be given a pleasant taste, say the EPFL researchers.
EPFL scientists have already achieved some successes. In 2017, for example, they developed an edible gripper made of gelatine that could lift an apple. Together with the Italian Institute of Technology (IIT) and the University of Bristol, they developed a conductive ink that uses activated carbon as a conductor and gummy bears as a binder to use as a sensor. In 2023, IIT researchers succeeded in developing the first rechargeable and edible battery. It consists of riboflavin (vitamin B2) and quercetin, a substance extracted from almonds and capers, in the battery poles. They used nori algae to prevent short circuits. The battery, which delivers 0.65 volts, has a beeswax casing.
In2022, the EPFL researchers, together with colleagues from the University of Wangeningen, built an edible drone with wings made of rice cookies glued together with gelatine. EPFL and the IIT have also developed edible rolling robots equipped with pneumatic gelatine legs and an edible tilt sensor, for example.
The work was developed as part of the RoboFood project created in 2021. The project aims to bring robots and food together and promote the development of digestible electronics and robot parts.
(olb)