A robotic cockroach – Harvard’s Ambulatory MicroRobot (HAMR) – can survive underwater. It is able to walk on land, swim on the surface of the water, and walk underwater for as long as required. This advanced robot works on foot pads which rely on surface tension for walking on land and induced buoyance for swimming and walking underwater. This reduces contact angle between water and material under voltage is applied, this process is known as electrowetting. This process makes easier to break the water surface.
While swimming, the pad assists to avoid submerged obstacles and reduces hindrance created by obstacles. Using asymmetric flaps and well-designed pads help the robot to swim. In case of misusing passive flaps, the robot generates gaits to swim forward and turn properly.
This robotic cockroach is highly leveraged by the small experiments based on Physics to work efficiently – surface tension and gaits. Application of small physics can improve performance significantly, said Kevin Chen, the author and one of postdoctoral fellow at Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS).
Size of the robot is key to perform well, the bigger size is a challenge to get proper support whereas small size might not generate required force to swim or walk, said Neel Doshi, a student at SEAS and co-author of the study. This HAMR is 1.65 grams that create a frequency of up to 10 Hz to paddle its legs. It has coated for water-proofing with perylene. These researchers expect that future experiments on it will improve its moving capacity, speed, and it will find its way to come back to the original position without a ramp.