Researchers at Rice University have created a soft robotic arm that can perform tricky tasks like moving around obstacles or hitting a ball. This arm is controlled and powered by laser beams from a distance, with no electronics or wires inside it. This innovation could lead to better ways of managing surgical tools inside the body or machines that handle fragile items.
The research combines smart materials, machine learning, and an optical control system. The researchers used a device that patterns light to move a robotic arm made from azobenzene liquid crystal elastomer, a polymer that bends when exposed to light.
This research is published in Advanced Intelligent Systems.
Achieving precise movements
The robotic arm uses a neural network trained to predict the right light pattern for specific movements. This makes it easier for the arm to handle complex tasks without complicated instructions from a person. Traditional robots have rigid parts like hinges or wheels, limiting their movement. Soft robots, especially continuum robots, offer more freedom to adapt, which is useful in medicine for working with delicate tissues. Continuum robots are a kind of soft robot that can move in many directions without fixed joints.
The researchers developed a new elastomer that shrinks under blue laser light and grows back in the dark, a feature called fast relaxation time that allows real-time control. Unlike other light-sensitive materials needing harmful ultraviolet light or long reset times, this one uses safer light and responds in seconds. By directing multiple laser beamlets to different arm parts, the researchers can make it bend or contract like an octopus tentacle, offering almost unlimited movement possibilities.
The arm moves in 2D now, but future versions could work in 3D with added sensors and cameras. This could lead to safer robotics for medical devices or industrial uses, supported by funding from the National Science Foundation and others.