Conventional robots made with rigid components play an essential role in modern times. But these robots have limited adaptability. With the future increasingly dependent on the ability to integrate robots into complex operating environments, there is a need for robots that are soft and compliant. Soft-bodied animals are an important source of inspiration for designing soft robots that can change form and are resilient and safe for humans. It’s challenging to design and fabricate soft robots given the difficulties in controlling high-performance soft actuators, especially when it comes to device integration. Tiefeng Li, professor at the Department of Engineering Mechanics at Zhejiang University, is a pioneer in the field of soft robots.
He has designed a soft electronic fish, drawing inspiration from nature. It’s mainly made of rubber and water, giving it a soft and transparent body. Actuators made of dielectric elastomer (DE) are embedded in the robot to form artificial muscles, giving the electronic fish high mobility. Contrary to the common belief that the entire DE assembly should be fully insulated, the design uses the water surrounding the fish as the electrode, taking full advantage of its ability to be a weak yet sufficient electric conductor. The overall design of the soft robot is compact and robust, and it can achieve a swimming speed of 0.69 body length per second, about twice the speed of previously reported untethered aqueous soft robots.
Inspired by living organisms, Li's soft electronic fish robot may pave the way for creating wearable devices that are soft and compliant, and can be used as a light and easy-to-use exercise aid for the elderly. It can also be used as a medical rehabilitation tool. Another possible application is the monitoring and exploration of complex environments. For example, the soft design of a robotic fish allows it to adapt to complex environments, which can be used for marine environmental monitoring and exploration.
Li said that after several years of development, China has made considerable progress in the field of soft robot research. An important goal for Li is to advance soft, smart material technologies by developing quick and precise mechanical modeling methods and design principles that scientists and engineers can easily use to develop innovations in their own areas.