All About Soft Robotics
The Evolution of Robotics
What we define as robotics is changing. The use of robots in the past was usually limited to repetitive, difficult movement of parts in industries such as automotive. These were big, heavy, metal machines that were made to perform a task that was probably dangerous for a human to do themselves.
Nowadays, the term "robot" is evolving. While many still have those industrial jobs that they used to, robotics also includes applications for transportation, security, tracking, and even companionship. They have begun to look drastically different as well, no longer the large, clunky metal machines that took over industries years ago.
What Is Soft Robotics?
Soft robotics, to put it simply, are robots that are soft (haha). They are made out of cushioned, flexible materials that allow them to handle delicate objects without destroying them, and can often perform motions more similar to humans than their metal counterparts can. Additionally, soft robotics can adapt to external forces from their environment. The ability to bend and adjust its shape can prove vital for success in unpredictable and changing situations.
These compliant materials have to rely on systems other than a rigid one for movement. This has led to some pretty impressive technological feats throughout the past decade or two, as ways to move soft robots were developed. One of the more common methods is pneumatics, changing the pressure within the material to either expand or contract the device. This method proves effective in picking up delicate objects.
Another frequent method is the use of thermal properties of a material. Shape memory polymers are reconfigurable materials that, when above a certain temperature, can be shaped a specific way and then cooled down. When introduced to heat again, it will revert back to its original shape. Lastly, a less frequent method of control is through electric fields. In certain situations, with certain materials, electrostatic forces can be used to change the shape of the robot. This is used less often not only because of the specific conditions in which it can be applied, but also due to the requirement of a constant high voltage, and how it is prone to breakdowns.
Applications of Soft Robotics
As stated previously, there are many uses for soft robotics, and their applications in the field are vital to many companies' success. One of the most common uses for these soft systems are gripping objects, such as the function of a claw machine. The compliant material can be suppressed when pressing against something, and a light pressure from a pneumatics system on the inside of the claw is enough to provide support for anything delicate, no matter how small the size is. They can pick up eggs and fruit, and even things as flat as cookies without damaging them. A minor drawback for this system, however, is that usually an additional mechanical system is required to operate the pneumatics effectively and correctly.
Soft robotics also aims to fix certain problems in the biomedical industry as well. Many people around the world suffer from conditions that restrict motor functions in one of or both of their hands, and a soft robotics application could provide them with assistance opening, and closing said hand. It can also provide support while holding day-to-day items. The material aspect of the field allows for the revolutionizing of prosthetics and shows great promise for technology on the millimeter or micrometer scale.
I am fortunate enough to have been on a team that explored some of the basic uses of soft robotics, going as far as constructing our own claw to try and pick up random household objects that fit in its diameter. Our claw was made of a rubber alloy and consisted of two pieces in a 3-pronged design. The top part was molded with just the rubber, but the bottom was molded with a strip of paper in it. This strip of paper prevented that piece from expanding when our pneumatics system increased the pressure inside of the claw. While it remained the same size, the top piece, without the paper, would swell when the pump was active.
When restrained with a thin fiber filament, the resulting action was the claw would curl towards the non-swelling piece, creating the movement of a claw. Our pneumatics system consisted of a small hand pump that had to be squeezed several times to fully close. Overall, not the prettiest product but served the purpose of starting our research into applications of soft robotics.
© 2019 Ryan Clancy