Scientists at the Ecole polytechnique fédérale de Lausanne (EPFL) in Switzerland have created a soft artificial skin that can sense touch while providing real-time haptic feedback. Because of its sophisticated self-sensing mechanism, the new skin has the potential to instantaneously adapt to a wearer’s movements. Scientists believe the new technology can be applied to numerous fields such as from medical rehabilitation to virtual reality (VR).
Our sense of touch, similar to our senses of hearing and vision, plays a crucial role in how we perceive and interact with the world around us. Haptic feedback – a technology capable of replicating our sense of touch – can greatly improve human-computer and human-robot interfaces for applications such as medical rehabilitation and virtual reality, reports EPFL.
A range of soft sensors and actuators in the artificial skin enable it to conform to the exact shape of a wearer’s wrist, for example, and provide haptic feedback in the form of pressure and vibration. Strain sensors continuously measure the skin’s deformation so that the haptic feedback can be adjusted in real time to produce a sense of touch that’s as realistic as possible.
“This is the first time we have developed an entirely soft artificial skin where both sensors and actuators are integrated,” says Harshal Sonar, the study’s lead author. “This gives us closed-loop control, which means we can accurately and reliably modulate the vibratory stimulation felt by the user. This is ideal for wearable applications, such as for testing a patient’s proprioception in medical applications.”
Soft pneumatic actuators in the artificial skin form a membrane that can be inflated by pumping air into it. A chamber, created by the membrane, can be inflated and deflated using a tiny pump up to 100 times per second, generating vibrations that will feel different to the user.
The artificial skin can be stretched up to four times its original length for up to a million cycles. That makes it particularly attractive for a number of real-world applications. For now the scientists have tested it on users’ fingers and are still making improvements to the technology.
“The next step will be to develop a fully wearable prototype for applications in rehabilitation and virtual and augmented reality,” says Sonar. “The prototype will also be tested in neuroscientific studies, where it can be used to stimulate the human body while researchers study dynamic brain activity in magnetic resonance experiments.”
This work was published in Soft Robotics.