A team of Chinese scientists have developed an intelligent material that is capable of curving and curling when external pressures are applied. The fluid motion resembles the mechanics observed in nature more closely than previously thought capable, and is planned for use in the soft- and micro-robotics industries.
The researchers, working out of Southeast University in Nanjing, published their work in the journal Applied Materials and Interfaces; they believe their new material may hold the key to robots moving more fluidly.
Scientists believe a new wave of smart materials capable of self-actuating and transforming independently will prove significant in a broad spectrum of industries, ranging from robotics to medicine.
The team set about creating a pair of robotic grippers that move more naturally, making the potentially complex and dangerous tasks it performs alongside humans, far safer.
Typically, creating that sort of mechanical action requires “complex, clunky dynamics”, something the researchers were looking to eliminate, they explain in a YouTube video. The robot grippers should also be capable of picking up fragile objects where even the smallest amount of pressure or force may cause damage, the team added.
The research team created what they called a “single-unit design” that more easily mimics intelligent and autonomous actions in nature – like stretching, shrinking and warping – when presented with external environmental stimuli such as heat, wetness and air pressure.
To facilitate that range of dynamic movement, the team applied a nickel-infused gallium indium alloy, a rare liquid metal, onto a liquid crystalline elastomer (LCE). Because of the unique elastic properties of LCE’s, they are widely used as a muscle analogue in soft- and micro-robotics.
Using magnetic power, the Chinese crew neatly arranged the rare liquid metal into grid-like lines, forming a closed circuit. A sealant was applied that turned pink to red when heat was applied; this served the dual role of protecting the unit by securing it correctly, as well as indicating if it was experiencing any significant warming.
The team then applied a myriad of external stimuli to their material and discovered, for example, that when a current was run through their smart material, it curled. It also changed from a pink to reddish hue over time, indicating warmth.
Using the insight gleaned from many experiments, the scientists developed the robotics grippers with this new material. Notably, the researchers demonstrated that the grippers could pick up small, spherical objects and place them down gently after small amounts of pressure were applied through the system.
The team also created a spiral-like arrangement with their material and demonstrated how the fabric would furl and unfurl naturally, with stimuli from a specific angle. These principles could effectively be used in robotics, especially where complex activities and movements are required, said the team.