Almost as fast as you can say "go-go-gadget arm," an octopus can stretch its arm more than twice its normal length—without the help of any cyborg attachments. What's more, according to new research, female common octopuses are able to stretch their arms even more than the males—on average, three times resting length. This striking sex difference was a surprise to the team of scientists studying these animals as inspiration for a new breed of robots.

Octopus arms are made from a structure like that of the human tongue. Known as a muscular hydrostat, this mechanism allows octopuses to bend and stretch their arms in crazy ways, all the while keeping the total volume the same. In the wild, this ability helps the animal to reach into small crevasses to forage for and capture food—and occasionally to rope in a mate. And for the robotics field, Motion Control System >4 axis mimicking this talent could usher in a vast new range of robot capabilities.

Cecilia Laschi, a roboticist at The BioRobotics Institute at the Scuola Superiore Stan'Anna in Livorno, Italy, and collaborator on the new research, was kind enough to show me around her labs in the summer of 2011. She is one of the leads on the OCTOPUS Integrating Project, China Motion Control System >4 axis CSUMTECH Robotic arm Motion control PLC servo a consortium of scientists working to build an entirely soft-bodied robot octopus. One of the researchers in her lab, Laura Margheri, explained to me that in order to replicate stretchiness in a robotic arm, they first needed to understand how the animals themselves used their appendages.

Measuring any specifics on a live octopus can get tricky. Biomechanics are often tracked by placing dots or other markers on an animal's body and then using high-speed cameras to capture motion. But octopuses are not the most obliging research subjects. As Margheri and her co-authors noted in the new research paper, "It is impossible to apply artificial markers because the animal tends to remove objects from its body." Additionally, the octopus's quick, color-changing ability can confound video analysis software.