Living organisms have inspired research into soft robotics that mimics the complex movement of animals and plants.
Until now, the main research on biomimetic robotics was based precisely on mimicking the complex movement of animals and plants, and developed robots have limited or no sensory capacity, one of the essential functions of natural intelligence. Now a team of researchers from the National University of Singapore has developed tiny light-powered robots that are capable of feeling. This is a great challenge, especially when the size of the robot is on a small scale, a few centimeters.
Scientists developed a soft robot that integrates compactly in a very thin film with a thickness of just 115 micrometers (µm, which is equivalent to one millionth of a meter) all this: a tension sensor, a temperature sensor and an actuator , which simultaneously enables reflex and locomotive capabilities.
This development will allow the manufacture of customizable miniature soft robots, with the virtue of simultaneous perception and motility, according to their creators, Ghim Wei Ho and Xiao-Qiao Wang.
How does it work?
The thin, flexible film includes a double-layer actuator that responds to light heat, sensing temperature of the pyroelectric polymer layer, and a sensing bending voltage of the piezoresistive circuit. It contains independent electrodes for the two sensors, facilitating separate piezoresistive resistance reading signals and without interfering with each other.
This light-driven somatosensory robot (SliR) is therefore capable of detecting tension and temperature simultaneously. It gives them complex perceptions of the state of their body, as well as the surrounding environments.
“Our composite allows for an arbitrary pattern of sensors and actuators, and can be transformed into various 2D to 3D prototypes through kirigami,” says Dr. Xiao-Qiao Wang, leader of the work publishing the journal Advanced Materials . “The dimensions of the robot can be easily reduced.”
Wang’s work has focused on designing several kirigami soft robot prototypes capable of proprioceptive (the perception of the internal state) and exteroceptive (the perception of external aspects) feedback. One of these prototypes is a robotic walker that provides feedback on your detailed steps, as well as subtle terrain textures when moving through different surface topography. Another prototype is an anthropomorphic hand that has somatosensory receptors, showing specific movements of the fingers, sensation of heat / cold, and perception of hardness / softness. Another design is a centipede that can wirelessly walk, turn, and sense light intensity, wind speed, and human touch.
Although they are still working to solve the problem of closed-loop power control between sensors and actuators, “we hope to achieve soft robots that can finally function autonomously, respond and adapt to changing environments such as living organisms,” the authors conclude. .
Referencia. Xiao-Qiao Wang, Ghim Wei Ho et al. “Somatosensory, Light‐Driven, Thin‐Film Robots Capable of Integrated Perception and Motility”, Advanced Materials (2020), DOI: 10.1002/adma.202000351
