The animal kingdom contains many examples of efficient forms of locomotion, so it's no wonder that we've been seeing a lot of animal-inspired robots – recent examples have included a robotic cheetah, fish and snake. Plants, however, just sit there ... don't they? Actually, they do move, just not necessarily in a Point A to Point B manner. With that in mind, Europe's PLANTOID project consortium is now in the process of developing a tree-like robot. Its descendants might ultimately find use in the exploration of other planets.
The base of the PLANTOID robot is a 3D-printed plastic "trunk," which houses a microprocessor. Extending out from the sides of that trunk are four plastic branches, the leaves of which are actually sensors capable of detecting and measuring factors such as temperature, humidity, gravity, touch, and chemical elements.
The robot's two roots, however, are where the real action is.
The robot on display, showing its tentacle-like and "growing" roots (bottom left and right, respectively)
One of those roots, which bends like a tentacle, has a tactile-sensor-equipped tip. Using that sensor, as it squirms its way through the dirt, the root can change direction when it encounters solid obstacles ... much like a natural root does. It could also be equipped to sense and avoid toxic substances in the ground.
The other root (seen below) is actually able to grow down into the substrate. It has a rotating tip, which extrudes a coiled cord behind it as it turns. The coils join together to form a tube-like root, which continues to grow as long as the tip keeps turning.
In its present form, the PLANTOID robot serves mainly as a proof-of-concept model. Down the road, however, the technology developed for its roots could lead to better endoscopic surgical tools, or for tools used in locating victims buried in debris at disaster sites.
Complete PLANTOID-type robots could be also used to monitor things like soil conditions and pollutant levels here on Earth, or they could even find use gathering environmental data on other planets. Once deposited by an unmanned rover, a PLANTOID could secure itself in place via its roots, then set about sensing the air and soil.
The project is being led by the Istituto Italia di Tecnologia, with the other members consisting of the Institute for Bioengineering of Catalonia (Spain), the Università degli Studi di Firenze (Italy) and EPFL (Switzerland). It began in 2012, and is due to wrap up next April. In the meantime, the researchers are looking into adding other functions to the roots, and devising ways in which the robots could draw power from their environment.