Artificial “Skin” Printed with Heat Sensors Could Increase Safety in Industrial Settings

In industrial settings, people and robots work side by side. This can increase efficiency, automate tasks, and enable processes that require such cooperation, but it does come with health and safety risks. However, if robots could be equipped with sensors that reliably detect humans in all directions, then these issues could be solved, and people could work alongside machinery that was previously too dangerous to be near. Though current sensors rely on electronics that are often too impractical, rigid, and thick, researchers at the Eindhoven University of Technology, or TU/e, have designed a new printing method to make flexible, thin, and accurate sensor electronics. Their research is published in Nature Electronics.

The newly designed sensors have been shown to outperform current sensors in many ways. Many sensors are based on silicon components and are rigid and thick, making placing them on the surface of a robot both difficult and costly. The alternative is flexible printed electronics, which can be placed over large surface areas and are cheap and easily produced. But current printed designs have lower capabilities than silicon chips — they’re slow and noisy, which negatively affects accuracy.

To solve both issues and make accurate, flexible electronics, TU/e researchers developed a new fabrication method, printing organic materials based on polymers. This approach allows for the placement of front-end electronics in each pixel of the device. In essence, the team printed electronics on two sheets of plastic or foil, then laminated the two sheets together. This combination produces an ultra-flexible and thin sensor with the improved signal quality compared to previous sensors.

When wrapped around a robotic arm, the sheets serve as an artificial skin where heat sensors pick up any moveable heat source — such as a person — up to 0.4 meters away. The sheets can also detect a human hand approaching from any direction, not just directly in front of it.

This new sensor fabrication method certainly has great potential in industrial applications, but the researchers also note that it could be useful in a number of other fields, including healthcare. Sensors could be used to map pressure distribution on mattresses and help avoid bedsores or be embedded in floors in homes with residents at risk of falling to detect falls. With some tweaks, it may even be possible to use this type of sensor to monitor the integrity of airplane wings. With this newfound promise in low-cost printed sensing surfaces, TU/e researchers are excited to carry their results into many new research endeavors.