Pushing Sensor Technology to New Limits through Non-Electric Touchpad

Researchers at Tampere University developed a soft, non-electric touchpad using pneumatic channels, which is ideal for environments like MRI machines, prosthetics, and soft robotics.

FREMONT, CA: Without electricity, researchers at Tampere University created the first soft touchpad in history to detect the location, force, and area of contact. Because it uses pneumatic channels, this device can be used in settings such as MRI machines and other inappropriate conditions for electrical equipment. This new technology may also help soft gadgets like rehabilitation aids and soft robots.

Entirely made of soft silicone, this soft touchpad device has 32 touch-adaptive channels that are only a few hundred micrometres broad. It can detect many simultaneous touches and is accurate enough to identify handwritten letters on its surface and determine the location, force and area of a touch.

According to doctoral researcher Vilma Lampinen, extreme environments, like a high magnetic field, can cause electronic sensors to malfunction. The touchpad is perfect for use in devices like MRI machines since it is not electric or affected by high magnetic fields.

For instance, a pneumatic robot can perform a biopsy while the patient is undergoing an MRI scan if cancerous tumors are discovered, thanks to the touchpad's sensor technology. Sensor technologies guide this robot, and the information is generated by MRI imaging.

The pneumatic device can also be employed in environments with high radiation levels or where even a tiny electrical spark could pose a significant risk.

Silicone's material flexibility allows sensors to be incorporated into applications unsuitable for conventional rigid electronics. These include soft robots, usually powered by pneumatics and composed of materials resembling soft rubber.

In the future, it would be feasible to map the location, force and area of contact throughout the entire surface of such soft, non-electric devices by incorporating sensor data. Adding a sense of touch to sophisticated prosthetic hands would be beneficial in addition to soft robotics. Prosthetic hands-on production lines, for example, could be replaced by soft robotic hands. They are safer, lighter and less expensive to produce because they are smooth. According to Lampinen, a more sensitive grip would also be made possible by touch sensors around the hand.

Shrinking the channels might increase touchpad resolution, but the wet bonding method, which clogs channels with thin adhesive films, is the bottleneck. In addition, the researchers would investigate sophisticated multitouch features with the goal of expanding the number of touches the sensor can recognise by pneumatic methods and detecting multiple touches without ambiguity.

Soft-material wearable technology may potentially be used as movement aids in rehabilitation. When compared to comparable complex equipment, softness enhances comfort.