At least as far back as 1967, when Richard Brautigan published his poem All Watched Over by Machines of Loving Grace, there has been interest in exploring the unlikely meeting place between cutting-edge technology and the natural world. In the latest example of this, engineers from Italy’s Istituto Italiano di Tecnologia (IIT) have developed what they claim is the world’s first tendril-inspired soft robot that’s able to climb and curl like real plants. The approach could one day be used to create futuristic wearable devices able to morph their shape depending on their situation.
“It is based on the imitation of the natural mechanisms by which plants exploit water transport inside their cells, tissues, and organs to move,” Barbara Mazzolai, director of IIT’s Center for Micro-BioRobotics, told Digital Trends. “The hydraulic principle is called osmosis, and is based on the presence of small particles in the cytosol, the intracellular plant fluid. Plants use this principle to tune their stiffness and achieve macroscopic movements. We have developed a tendril-like soft robot [that is capable] of reaching and anchoring to an external support. The soft robot is made of a flexible PET tube, containing a liquid with electrically charged ions. By using a 1.3-volt battery, these particles are attracted and immobilized on the surface of flexible electrodes at the bottom of the tendril. Their movement cause the movement of the liquid, [and resultantly also that] of the robot.”
The robot tendrils’ movements can be reversed by disconnecting the electric wires from the battery. The research represents the first stage of a new project, called “GrowBot,” funded by the European Commission. It seeks to develop a robot that’s able to grow and adapt to its surrounding environment, including recognizing the surfaces it attaches to.
“Soft robots may permit [robots] to interact safely with objects or living beings,” Mazzolai continued. “Possible applications will range from wearable technologies to the development of flexible robotic arms for exploration.” While she acknowledges that “the challenge of imitating plants’ ability to move has just begun,” this proof-of-concept demo nonetheless represents an exciting step in the process.
A paper describing the robot tendril project, titled “A variable-stiffness tendril-like soft robot based on reversible osmotic actuation,” was recently published in the journal Nature Communications.