This artificial muscle works on the principle of coiled-up substances. They can stretch like a muscle. Twisting up even a simple material like sewing thread or fishing line creates a muscle-like structure that can lift weights 100 times heavier than what a human muscle can manage. Bamboo or silk are even stronger fibers, when twisted into a coil and coated with a sheath that can respond to heat or electrochemical changes, which can trigger the muscle to contract and thus move.
It was noticed that even a slight increase in the temperature made the coil tighten up, producing a surprisingly strong pulling force. The moment the temperature dropped down, the fiber returned to its original length. It was observed that this process of contraction and expansion could be repeated 10,000 times. Even a 1-degree Celsius increase was enough to start the fiber contraction.
However, engineers still have to go a little far to make these artificial muscles as efficient as ours. Currently, nearly 3 percent of the energy put into these muscles is used by the fibers. The rest of it is lost in the form of heat. Once this problem is fixed, these artificial muscles and others of their form, could provide cost effective and slimline alternatives to the bulky electric motors used today.
Watch this video to know how it works!
Such fibers could be used as actuators in robotic arms, legs, or grippers, and in prosthetic limbs, where their small weight and instantaneous response could provide a great advantage. Also, it can find uses in tiny biomedical devices, such as a medical robot that does it work by entering an artery. Activation times in the order of tens of milliseconds to seconds, makes it more beneficial.
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