Robotics and mechanization have improved leaps and bounds over the past decade. That said, gesturing naturally, grasping objects with suitable pressure, touching and feeling an objects shape and texture, and doing other similar actions are not yet a given. Those actions represent a complex sequence within the bodies of humans and other animals, and artificially reproducing natural gestures, pressure, and sensation presents a challenge—one that engineers are attempting to meet through lightweight and compact motors and precise and programmable actuators.
Once only the subject of Hollywood blockbusters, today’s robots are increasingly part of everyday life, interacting with humans in more natural, anthropomorphic ways. At one time, robots were only really used in situations too arduous or dangerous for humans or in situations requiring skill or strength beyond human capabilities. The classic examples of this are assembly-line robots, robotic manipulators in space applications, and battlefield robots that seek mines or improvised explosive devices.
More recently, though, robots are appearing in people’s homes as automated vacuum cleaners, lawn mowers, and toys. As they become ever more affordable and accessible, they are showing up in other environments, too, in a wide variety of applications, from medicine to farming to scientific exploration and textile assembly lines—some of which is very delicate work indeed.
While ye old robots were rigid—which made sense for fast, highly precise repeated motions, especially when manipulating heavy components—new use case scenarios are mandating the emergence of different kinds of robots, more matched to the various environments they are now having to operate in.
Soft robotics use soft, compliant mechanisms and actuators, built using fluids and flexible materials, enabling a wide range of motion, making them more useful for things like exoskeletons or wearables. Many are more lightweight than their more rigid counterparts, with muscle-like actuation; soft skin attachments; and electronically releasable spring elements.
Engineers are also researching the effects of electroactive polymers, electroadhesion gripping, and electrolaminates in soft robotics—all developments that can ultimately help humans blend comfortably with robots for super-human strength and/or ability.
Things like artificial muscle have the potential to fundamentally shift the way many types of industrial, medical, consumer, automotive, and aerospace products are powered and operated (for example), because they offer significant advantages over typical electromagnetic-based technologies, being lighter, smaller, quieter, and cheaper. They also offer more controllable and flexible configurations and enable robots to mimic the dexterity and mobility of humans.
Building machines that can replicate the delicate touch of a human hand is hugely complex. Scientists in the soft robotics field have tried all kinds of crazy things, from squishy blobs to boa constrictor-inspired claws to electroadhesion. Scientists have also made progress developing soft grippers that act like the thumb and index finger on a human hand, using layered flaps and pre-stretched elastomers with silicone skin coatings.
Creating robots from polymers—specifically, elastomers with moduli comparable with human skin—automatically eliminates many safety concerns with human robot interactions.
Next-generation wearable robots, therefore, will use soft materials like textiles and elastomers to provide a more comfortable, unobtrusive, and compliant means to interface with the human body. As well as offering super-human abilities and strength, wearable robots could—perhaps more practically—assist with patients who suffer from physical or neurological disorders.
There are approximately four million chronic stroke survivors with hemiparesis in the US today and another six million in developed countries globally. In addition, there are millions of other individuals suffering from similar conditions. Obviously, this can greatly inhibit ones daily activities and can considerably reduce one’s quality of life, but having robotic exoskeletons with abilities to turn an immobile human being into a mobile and capable one again is invaluable.
We’re already seeing the emergence of prosthetic skin that is warm and elastic like real skin and packed with various sensors. This could soon help people with prosthetic limbs regain their sense of touch.
In recent experiments, researchers laminated “electronic skin”—prosthetic skin embedded with electronics—onto a prosthetic hand. They found the skin could survive complex operations, such as shaking hands, tapping keyboards, grasping baseballs, holding hot or cold drinks, touching dry or wet diapers, along with touching other people.
The electronic skin proved to be as sensitive as expected to pressure, stretching, temperature and dampness, successfully relaying data rapidly and reliably.
The scientists also included heating devices throughout the prosthetic skin that could make it feel at least as warm as a person’s body temperature.
The research is inspiring the design of new materials and technologies able to sense certain cues, such as pressure, forces from different directions, vibrations, etc. It’s also thought that the ongoing development in soft robotics will help humans increasingly react or adapt to unexpected situations.