It is likely that when you think of muscles and strength, you think more along the lines of Arnold Scwarzenegger than Steve Urkel. That is where you’d be mistaken. Engineers are flexing their intellectual muscles by showing that small can be strong. Really strong.
An effort to improve artificial muscles has led to the discovery that simple materials can achieve extraordinary tasks. In article entitled “Artificial Muscles from Fishing Line and Sewing Thread,” an international research team shows that these two, low cost materials can achieve some remarkable tasks.
The recent advancement uses coiled nylon as the functional material. This starting material is what is commonly used for fishing line or for sewing thread. The coiled nylon is created by holding one end of a filament and twisting it to create a uniform coil. When heated, that coil will contract. Sets of these coils are then woven together to form a “muscle.”
While the processing just described seems simplistic, the process really is simple. Where processing sophistication is often associated with complexity, this is a welcome breath of fresh air. The process is highly adaptable too. By adjusting the nylon filament diameter, coiling parameters, weaving characteristics, etc. these artificial muscles can be tailored for a variety of uses.
The number of uses is expected to be inflated by the low cost and high strength. The authors state these artificial muscles can contract by 49% and lift loads 100 times heavier than the human counterparts. The improvement this presents over traditional movement, especially in robotics, comes from reduced weight and complexity over electric motors and hydraulic and pneumatic systems and greater configurational flexibility as well.
Because the strength at small size is very good, the ability to incorporate fine movement in tight spaces is possible, and the shape change effect under stimulus can be useful for more than actuation as well. Artificial muscles are not new, but they have traditionally had limitations in regard to cost and performance which are being addressed through continuing work. Here we have innovative ideas proving that small can be strong and strong can be cheap
The video below shows the contraction of one of these "muscles" used to lift a weight.
Image courtesy of helpingadvisors.com