Bio-Inspired Active Fiber Composite Pumps

Squid are the fastest aquatic invertebrates through jetting locomotion. This done through a mantle that quickly compresses an internal fluid, forcing fluid out through a funnel. The squid mantle has a complex collagen fiber and muscular system and squid propulsion is primarily done through circumferential muscles (90°) contracting around the mantel, forcing fluid out of the mantel. However, jetting is also increased through elastic energy stored in the helically-wound IM-1 collagen fibers, which have been measured between 28° to 32° in different species of squid. Inspired by the muscular and collagen fiber configuration found in the squid mantel, new composite pumps with active fibers oriented at precise angles around a cylindrical tube are proposed. An analytical model of the active fiber composite pump is developed. Results show that maximum pumping power and efficiency is achieved with a wind angle of 90° and a matrix modulus that is equal to the fiber modulus.