Researchers create most human-like robot skin yet

Humanoid robots capable of walking upright, such as those developed by Boston Dynamics, seem to make rapid progress week by week. Yet, they still fall short of replicating the full range of human abilities, particularly the capacity to perceive sensations like touch, temperature, and pain. Despite ongoing efforts to equip robots with sensory systems, current technologies often suffer from high costs, limited accuracy, and the inability to detect multiple stimuli simultaneously.

However, recent advancements suggest this gap may soon narrow. Researchers from the University of Cambridge and University College London have engineered an innovative form of “artificial skin” that responds dynamically to various physical stimuli. Crafted from a single hydrogel material, this synthetic epidermis can sense touch, pressure, heat, cold, and even damage-mirroring the sensory functions of human skin more closely than ever before.

In their experiments, scientists molded this hydrogel into the shape of a human hand and fitted it onto a robotic limb, functioning like a flexible glove. This adaptation allows the robot to perceive its environment with heightened sensitivity. Although still in the developmental phase, experts believe that such synthetic skin could revolutionize how robots operate in complex, hazardous, or unpredictable settings-ranging from manufacturing plants to disaster zones. The research findings were recently published in the journal Science Robotics.

While the concept of synthetic skin isn’t entirely new, significant progress has been made over the past decade. Since around 2016, researchers have demonstrated that integrating small sensors into robotic fingertips and palms can help machines recognize object shapes and textures. However, combining multiple sensory capabilities into a single system has historically been complex and prone to issues like signal interference, known as “crosstalk,” which hampers accuracy and can even damage sensors.

“Creating separate sensors for each type of touch results in intricate and fragile designs,” explained Dr. David Hardman, a lead researcher from Cambridge. “Our goal was to develop a unified material that can simultaneously detect various stimuli, simplifying the design and improving reliability.”

To achieve this, the team employed a flexible, conductive hydrogel made from gelatin-like substances that can stretch and deform without losing functionality. This material translates physical inputs-such as heat, pressure, or damage-into electrical signals that are processed by a computer. Remarkably, the hydrogel contains over 860,000 embedded pathways, allowing it to detect multiple stimuli at once with high resolution. The team subjected the synthetic skin to various tests, adjusting its properties to optimize responsiveness.

Related: [Lab-grown, self-healing human skin designed to cover robot faces]

This synthetic skin isn’t just a static material; it can be reshaped and reconfigured. In experiments, researchers molded it into a form resembling a battered work glove-yellow and black in color-and fitted it onto a robotic hand. When pressed or lightly swabbed, the glove could distinguish different pressure levels. It even responded to a “heat blast,” melting partially under high temperatures, and was sliced open with a scalpel. Despite these rough treatments, the skin maintained its ability to sense various stimuli, demonstrating resilience and versatility. While it doesn’t yet match the sensitivity of human skin, it surpasses existing multi-sensor systems in simplicity and performance.

Thomas George Thuruthel, a researcher at University College London and co-author of the study, remarked, “Our synthetic skin isn’t quite as sensitive as human skin, but it’s currently the most capable and adaptable solution available. Its flexible design makes it easier to manufacture, and we can calibrate it using human touch data for different applications.”

Advancing Toward Sensory-Enabled Robots

The extensive testing-poking, heating, and slicing-serves a practical purpose: demonstrating that this synthetic skin can be molded onto various robotic parts and still retain its sensing abilities. Such robots could navigate complex environments, whether in automotive assembly lines or construction sites, with a level of tactile awareness approaching that of humans. This capability is especially crucial for humanoid robots designed to work alongside humans, such as those being developed by companies like Figure and Tesla. For instance, a robot handing over a hot cup of coffee or a fragile object needs to sense temperature and pressure accurately to prevent accidents or damage.

Currently, companies like Figure are testing humanoid robots in manufacturing settings, such as BMW’s plant in South Carolina. Meanwhile, Amazon is reportedly training robots to handle and deliver packages, hinting at a future where robots with human-like sensory perception could become commonplace in everyday life.

In essence, the development of this synthetic skin marks a significant step toward creating robots that can “feel” their way through the world, opening new possibilities for automation, safety, and human-robot collaboration.