Bend It Like a Bot: New Model Enables Biological Movement In Soft Robots

Robotic movement is generally thought to be abrupt and mechanical but researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and the Wyss Institute for Biologically Inspired Engineering have teamed up to develop a method to design a soft robot with the capability to move organically.

Publishing their research in Proceedings of the National Academy of Sciences, coauthor Katia Bertoldi, the John L. Loeb Associate Professor of the Natural Sciences, explained the main idea behind their study. "Rather than designing these actuators empirically, we wanted a tool where you could plug in a motion and it would tell you how to design the actuator to achieve that motion."

Even seemingly easy movements like bending a finger or twisting a wrist is complex for a soft robot. First author of the study Fionnuala Connolly, a graduate student from SEAS, elaborated: "The design is so complicated because one actuator type is not enough to produce complex motions. You need a sequence of actuator segments, each performing a different motion and you want to actuate them using a single input."

Utilizing a mathematical modeling of fluid-powered, fiber-reinforced actuators to optimize the design of an actuator to perform a certain motion, the research team was able to design a soft robot powered by a single pressure source that has the ability to bend like an index finger and twist like a thumb.

Another coauthor of the study, Conor Walsh from the Wyss Institute for Biologically Inspired Engineering, believes the research could lead to more progress in the field of robotics. "This research streamlines the process of designing soft robots that can perform complex movements. It can be used to design a robot arm that moves along a certain path or a wearable robot that assists with motion of a limb."