“Manufacturing and underwater cyclic behavior of different types of twisted and coiled artificial muscles (TCAMs)”

Twisted and Coiled Artificial Muscles (TCAMs) are a recently developed class of artificial muscles manufactured from inexpensive polymer fibers that possess the characteristic of anisotropic volume expansion. Supercoiling these fibers produces a helical geometry which can be altered electrothermally to produce an axial contraction. In this work we demonstrate a manufacturing process using off-the-shelf components to automate the process of manufacturing and produce TCAMs with repeatable performance characteristics utilizing two methods of production: self-coiling and mandrel-coiling. This manufacturing system also facilitates the production of TCAMs in a wide range of sizes and greatly improves the success rate for producing useable samples when compared to current methods. In addition, we investigate the suitability of various polymer fibers for use in manufacturing of TCAMs through cyclic testing in simulated environments and find that nylon 6 and polyvinyl difluoride offer an attractive blend of repeatable performance and suitability in a variety of simulated environmental conditions.