Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea

Soft pressure sensors have received significant research attention in a variety of fields including soft robotics, electronic skin, and wearable electronics. Researchers have developed a highly sensitive wearable pressure sensor capable of sensitive, precise, and continuous measurement of physiological and physical signals and shows great potential for health monitoring applications and the early diagnosis of diseases.

A soft pressure sensor is required to have high compliance, high sensitivity, low cost, long-term performance stability, and environmental stability in order to be employed for continuous health monitoring. Conventional solid-state soft pressure sensors using functional materials, including carbon nanotubes and graphene, have showed great sensing performance; however, these sensors suffer from limited stretchability, signal drifting, and long-term instability due to the distance between the stretchable substrate and the functional materials.

To overcome these issues, liquid-state electronics using liquid metal have been introduced for various wearable applications. Of these materials, Galinstan — a eutectic metal alloy of gallium, indium, and tin — has great mechanical and electrical properties that can be employed in wearable applications. But today's liquid metal-based pressure sensors have low pressure sensitivity, limiting their applicability for health monitoring devices.

The researchers developed a 3D-print-ed, rigid microbump array-integrated, liquid metal-based soft pressure sensor. With the help of 3D printing, the integration of a rigid microbump array and the master mold for a liquid metal microchannel could be achieved simultaneously, reducing the complexity of the manufacturing process. Through the integration of the rigid microbump and the microchannel, the new pressure sensor has an extremely low detection limit and enhanced pressure sensitivity compared to previously reported liquid metal-based pressure sensors. The proposed sensor also has a negligible signal drift over 10,000 cycles of pressure, bending, and stretching and exhibited excellent stability when subjected to various environmental conditions.

These performance outcomes make it an excellent sensor for various health monitoring devices. First, the research team demonstrated a wearable wristband device that can continuously monitor one's pulse during exercise and be employed in a noninvasive, cuffless blood pressure monitoring system based on PTT calculations. Then, they introduced a wireless, wearable heel pressure monitoring system that integrates three 3D-BLiPS with a wireless communication module.

For more information, contact Professor Inkyu Park, KAlSTMicro/Nano Transducers Laboratory, at This email address is being protected from spambots. You need JavaScript enabled to view it. or visit here .

This article first appeared in the May, 2022 issue of Tech Briefs Magazine.

Read more articles from this issue here.

Read more articles from the archives here.

Jumping Robot Leaps to Record Heights

Predict Battery Lifetimes with Machine Learning

Using Silver Sintering in Traction Inverter Assembly

Novel Ink 3D Prints Bone with Living Cells

Lessons from How Dragonflies Right Themselves While They're Falling

EV vs. ICE: How Does Wire Harness Design Differ?

Get Even More Out of Your EVs with Thermoplastics

Advances in Unmanned Aircraft Technology

EV Battery & Electrification Testing – From the Grid to the Road

Simplify & Streamline Development of ISO 26262 Compliant Automotive SoCs

Automated Driving for Short- and Long-Haul Trucking: Are Drivers Really Yesterday’s News?

Preparing for the Cabin Cooling Transition: R-134a to R-1234yf

Direct Metal Laser-Sintering of Titanium

Test Strategies to Track Hypersonic Threats

Choosing the Right Brake for Robotic Applications

How to Make an RFID Chip Even Smaller

3 Challenges with Hydrogen Powered Engine Adoption

By submitting your personal information, you agree that SAE Media Group and carefully selected industry sponsors of this content may contact you and that you have read and agree to the Privacy Policy.

You may reach us at privacy@saemediagroup.com.

You may unsubscribe at any time.

© 2009-2022 Tech Briefs Media Group