By Veronica Rarick

A skin-like sensor, which allows users to feel their surroundings, could change the lives of amputees. The sensor, created by Stanford University engineers, can detect everyday forces like heat and pressure.

This new development may change the science of prosthesis. The sensor is made from a stretchy material that can adjust to the wearer. It is a printed circuit covered in carbon nanotubes, a nanotechnology used for its beneficial properties. These carbon structures are incredibly withstanding: in tensile strength, carbon nanotubes are the strongest making them perfect for the sensor.

The nanotubes can also conduct electricity, which can propel signals to the brain, much like synapses in the body already do.

“The innovation in our work is that we use pressure sensors coupled with a flexible circuit layer. The combination of the two things produces signals that are compatible with the human body, more specifically used for prosthetic type application,” said Alex Chortos, the first author of the Stanford study.

When the nanotubes are compressed, electricity is conducted. Once applied pressure, the nanotubes produce individual electrical pulses that can be transmitted to the brain, where the pulses are translated to the sensation of touch.

“The pressure sensors prior did not use electricity, we need the electricity for the circuit to function,” said Chortos. “It makes the circuit conductive and we need the electricity so the sensor can function.”

The research team would like to start testing on live animals rather than what they have been testing on, cells in a petri dish. After further research, the discovery could revolutionize the prosthetic field.

“The next step would be putting the receptor on the bottom of a mouse. In that case, we need to make the circuit more mechanically robust so it can withstand a freely moving animal. Another thing would be to improve the mechanical abilities, which we are working on currently,” said Chortos.  

The individual components of the sensor can be used for other fields like TV displays, robotics and automotive businesses.

“The sensor is an optimistic seven years, or more away until a possible commercial version is available.” said Chortos.