Researchers in the Massachusetts Institute of Technology (MIT) Department of Mechanical Engineering are developing the biomimetic RoboClam smart anchor. The RoboClam is a lightweight anchor that can be clamped, unclamped, and moved easily even in reverse (which can be quite difficult for traditional anchors). The robotic anchor is also helping to shed light on the behavior of the razor clam, the clam they’re using as a basis for their design.
Professor Anette Hosoi and her graduate student Amos Winter are designing the robotic clam with the assistance of engineers at BlueFin Robotics Corporation in a project sponsored by BlueFin, Batelle, and Chevron. Hosoi has spent the past several years working on novel propulsion methods inspired by nature, and when asked to design a light, easily movable anchor, she looked for animals that move effectively through the sediment on ocean floors.
After looking at other possible animal models, Hosoi settled on the razor clam. Razor clams are about seven inches long and one inch wide and can dig at a rate of a centimeter per second up to around 70 centimeters deep in total. Unfortunately, initial models of the clam failed to replicate these results. Winter determined that the clams were not physically strong enough to dig so quickly or deeply and set out to discover how they overcame this problem.
It turns out the razor clams stir the sand repeatedly and quickly until it mixes the sand and water together to form a sort of quicksand-like substance with a much lower drag than the dry, granular sand present at the start. This allows the clam to penetrate sand that otherwise would be beyond its capabilities.
Winter was able to replicate this behavior and penetrate a glass bead and water mixture with a new robotic clam. The roboclam itself is about the size of a standard cigarette lighter, but at the current time it’s tethered to an extensive array of mechanical equipment. Presumably, the next step is an untethered model that can operate on its own in real world conditions. Some of the tasks an untethered RoboClam could perform include anchoring small robotic surveillance vehicles, anchoring equipment designed to monitor changing water currents or other similar variables, and detonating buried underwater mines.
TFOT has reported on other innovative biomimetic robots including the GhostSwimmer robot modeled on the tuna, a jumping robot inspired by grasshoppers, a six inch robotic spy plane inspired by bats, an amphibious robot that can both swim and crawl inspired by sea snakes, and military surveillance robots inspired by spiders.
You can read the MIT press release about the RoboClam here. View an MIT TechTV video of a real razor clam digging through the sand here. You can also find more about the head researcher Dr. Anette Hosoi here.