Harvard’s Next-Gen Robotic Cockroach Set to Explore Underwater Environments

Everybody knows cockroaches will end up outliving the human race, considering they can survive a nuclear explosion, brutally cold weather, being submerged underwater for 30-minute, and live without a head for about a week. Harvard engineers were so impressed with their survivability; they decided to mechanize the insects and turn them into Ambulatory Microrobots (not literally) that are both quick and resilient. Those same engineers have since created a next-gen model, capable of walking on, and underneath the water.

The original Harvard Ambulatory Microrobot (HAMR) was powered by eight piezoelectric actuators, giving each leg two independent DOF. This allowed the robot to run, jump, turn on a dime and carry heavy payloads across long distances, all without injuring itself due to its low mass/density and high surface area.

The updated version of the HAMR still uses the same hardware as the original version for locomotion but has been outfitted with electrowetting pads and passive flaps. Those flaps are connected to central rigid support on each leg and retract under drag forces, enabling it to maneuver on water. Since the robot only weighs 1.6 grams, it can’t break the surface tension of water, which is where the electrowetting pads come in, as they can break that tension with a little-applied voltage.

Once underwater, the flaps help it swim and move in any direction, with gaits similar to a diving beetle. To transition back to land, the engineers provided a more robust transmission drive and soft pads on the robots front legs to re-break the surface tension and to walk up inclines to reach land. Unfortunately, the only way for the tiny robot to exit water is to use an incline, but the engineers hope to overcome this obstacle by using gecko-inspired adhesives or using robust jumping mechanisms.