22-12-2020 | By Robin Mitchell
Recently, researchers have created a small robotic system that can operate underwater, be controlled using light and external magnetic fields, all while using no electronics. What advantages do electronic-free robotics provide, what is this miniature robot capable of doing, and how could such designs be used in the future?
When the term “robotics” is used most would immediately think about an electromechanical creation commonly found on factory floors, and they would be right to do so. Almost all robotic systems currently used are built around ridged mechanical parts that are linked together using motors to provide movement.
One of the more common robotic systems is the robotic arm, and these provide industrial sites with a range of different capabilities including packing, welding, probing, and object manipulation. Other robotic systems also exist such as delta robots which utilise spider-like arms connected to a platform that is ideal for fast picking operations on conveyor belts.
However, an emerging field called “soft robotics” may change how people view robotics in general. Soft robotics is the field of robotics that utilises soft and compliant materials so that the resulting robots are malleable, flexible, and somewhat organic (in motion). Soft robotics can include specialised air-pumped grippers that allow a robotic arm to grab multiple types of objects without needing complex feedback systems to control the grip.
Soft robotics presents several advantages over traditional robotics, but their early stage of development means that these robots are yet to be deployed in any practical sense.
One of the first advantages that soft robotics have over their ridged counterparts is that they are organic in nature, and thus can flex and adapt to their environment better. For example, their soft nature allows them to handle objects without needing precise strength control (i.e. a soft gripper can easily pick up both an egg and a cup separately using roughly similar control systems).
Soft robotics also have the ability to mimic motion found in living organisms. For example, a soft robotic caterpillar could replicate the motion of a caterpillar that would allow it to navigate uneven surfaces with ease. Other organisms that soft robotics could be made to replicate include insects, fish, and birds.
When researchers make announcements, they are often underwhelming in nature, or the media blow the researchers announcement out of proportion. However, researchers from Northwestern University have created a four-legged soft robot that operates underwater, can perform different types of motion and tricks and can move around items.
Initially, I had thought that the researchers created four different robots all pre-configured to perform a specific action that would be incredibly underwhelming, or that the robot takes a very long time to change shape, but video footage of the single robot in action demonstrates its capabilities which are significant to say the least.
The soft robotic system does not utilise electronics, mechanics, or hydraulics to move, but instead utilises magnetic fields and light. The robot is made using a hydrogel that has ferromagnetic nanowires and changes shape when exposed to light. Furthermore, when exposed to an external rotating magnetic field, eddy currents in the nanowires cause the material to experience a force allowing for manipulation.
To demonstrate its capabilities, researchers were able to show the system walking, rolling, and transporting cargo at practical speeds. The system is also able to operate underwater, or in small cramped spaces which demonstrates its ability to work in tough environments. However, the practicality of a robotic system that requires light and magnetic influence is not entirely great, but the ability of the researchers to perform many different tricks shows that this is the most practical to date.