Our imagination of robots has been stuck in the iron age. Science fiction seems only to invent bigger, sleeker versions of wind-up toys, or the Tin Man from Wizard of Oz. Recent innovations may (literally) soften that view, opening up new horizons in rescue operations, elderly care, and environmental crises.
The field of soft robotics made bold strides this summer, starting with breakthrough research lead by engineers at Harvard University. That paper, published in Nature, described the world’s first completely soft and flexible robot.
The end of hardware?
Gone was the aptly named “hardware,” replaced by a complex system of soft chambers. As the chambers pump hydrogen peroxide in and out of hollow pockets in the materials, it sparks small-scale combustions with platinum that inflates (and deflates) specific chambers. The result: a flexible, autonomous robot, dubbed “the Octobot” because of its resemblance to the eight-legged octopus. The organic parallels are so strong, it might even feel awkward to call it a “machine.”
Elsewhere in the world of robotics, researchers are turning to the human body for inspiration – and impact.
Some recent examples come from the École polytechnique fédérale de Lausanne (EPFL). There, breakthroughs are taking place in the exploration of novel materials and textures that we may not yet associate with robotics. They seem almost food-like, more easily mistaken for sushi or sausages than Wall-E or R2-D2.
These machines are formed from silicon and rubber, intended to be fully safe and secure not just near, but potentially inside, the human body. Much like the octopus, these machines are all about air pressure, relying on the inflation and deflation of small balloons to shift their form and shape, some reaching six or seven times their original length. Importantly, the researchers were also able to predict how these machines would bend.
They’ve also shared kits for students and roboticists to build their own versions. The hope is that more models out in the world creates more data, and a deeper understanding of how they move.
The future is squishy
The principles are straightforward: researchers want a soft machine to interact with soft surfaces. The limits on robotic utility have been tied to those anxieties; nobody wants hard steel dealing with fragile objects, particularly if those objects are internal organs. Adding soft materials to the robotic toolkit expands the field into medical fields and environmental uses that may not have been possible.
That’s one test case for the EPFL’s robots. The researchers have paired up with patients at the University Hospital of Lausanne, where the devices are worn as belts, supporting the patient by restoring motor control and awareness. This application, dubbed co-robotics, opens up medical options through wearable skins or embedded machinery that could help patients walk, grasp, or accomplish other tasks.
“Using soft actuators, we can come up with robots of various shapes that can move around in diverse environments,” writes Jamie Paik, director of the Reconfigurable Robots Lab at EPFL, who noted that the combination of low-cost materials and flexibility helps the machines enter into hostile or dangerous situations.
That means soft robotics could transform emergency rescue operations and elderly care. Machines could lift and carry patients or the wounded. In disaster recovery, “soft” arm or lift mechanisms could be attached to heavy machinery that doesn’t come into contact with injured people.
The next breakthroughs in soft robotics will likely directed at autonomy. Most soft robots continue to struggle with an untethered life. Notably, the “life span” of the Octobot is somewhat limited. The researchers aimed for 12 minutes of autonomy, but yielded only eight (that said, the Wright Brothers only flew for 59 seconds – and just 66 years later, man reached the moon).
Another setback: the robot, much like a real octopus, isn’t particularly responsive to commands. While the flow of combustible liquids yields movement, it doesn’t always yield the movement you’d want. Nonetheless, as proof of concept, this opens the gate to a wide range of new technologies.
Likewise, the next step for soft co-robotics will be the reduction of size for the bulkier machinery, such as energy source and control mechanisms. That would move these machines closer to full functionality in practical applications.