Stanford engineers develop pressure sensor to advance prosthetics, medicine

Engineers at Stanford University have developed a tiny sensor used to measure the brain pressure in lab mice that they believe has the potential to create the electronic equivalent of touch for advanced prosthetics as well as other applications in medicine.

The wireless device, which is small enough to fit inside the ear of President Franklin Roosevelt's portrait as it appears on a dime, was also used by the Stanford research team to read the pulse of one of its members without touching him. A more complex experiment involved placing the sensor inside the skull of a lab mouse to measure the pressure on its brain, which the team also said could lead to improvements in how brain injuries are treated.

Zhenan Bao

"The device we invented here is extremely easy to manufacture and consumes no energy until readings are being made," Zhenan Bao, the team leader, said in a statement. "In the short term we hope to use devices like this to track packages and monitor health conditions. In the longer run we dream of using this technology to create touch-sensitive lining for prosthetic devices."

The team developed the wireless sensor by placing a thin layer of specially designed rubber between two strips of copper, which act like radio antennas. The rubber serves as an insulator. Radio waves are then beamed at the device. When the device comes under pressure, the copper antennas squeeze the insulator and move closer together.

That action changes the electrical characteristics of the device, and the frequency of the radio waves reflected from it slow down. When the pressure is relaxed, the copper antennas move apart and the frequency of the radio waves increases.

Physicians working with the team are also looking into additional uses for the device such as measuring the pressure in the eye socket as well as monitoring blood pressure.

- check out the Stanford release
- read the abstract