RIVERSIDE, Calif. (www.ucr.edu) Military body armor and vehicle and aircraft frames could be transformed by incorporating the unique structure of the club-like arm of a crustacean that looks like an armored caterpillar, according to findings by a team of researchers at the University of California, Riverside's Bourns College of Engineering and elsewhere published online today, June 7, in the journal Science.
The bright orange fist-like club of the mantis shrimp, or stomatopod, a 4-inch long crustacean found in tropical waters, accelerates underwater faster than a 22-caliber bullet. Repeated blows can destroy mollusk shells and crab exoskeletons, both of which have been studied for decades for their impact-resistant qualities.
The power of the mantis shrimp is exciting, but David Kisailus, an assistant professor at the Bourns College of Engineering, and his collaborators, were interested in what enabled the club to withstand 50,000 high-velocity strikes on prey during its lifespan. Essentially, how does something withstand 50,000 bullet impacts?
They found that the club is a highly complex structure, comprised of three specialized regions that work together to create a structure tougher than many engineered ceramics.
The first region, located at the impacting surface of the club, contains a high concentration of mineral, similar to that found in human bone, which supports the impact when the mantis shrimp strikes prey. Further inside, highly organized and rotated layers of chitin (a complex sugar) fibers dispersed in mineral act as a shock absorber, absorbing energy as stress waves pass through the club. Finally, the club is encapsulated on its sides by oriented chitin fibers, which wrap around the club, keeping it intact during these high velocity impacts.
"This club is stiff, yet it's light-weight and tough, making it incredibly impact tolerant and interesting
|Contact: Sean Nealon|
University of California - Riverside