Adaptive Impedance Matching Network for Contactless Power and Data Transfer in E-Textiles

Area of Science:

• Materials Science
• Electrical Engineering
• Wearable Technology

Background:

• Connecting flexible e-textiles to rigid electronics presents a significant challenge.
• Conventional galvanic connections limit mechanical reliability and user experience in e-textile applications.

Purpose of the Study:

• To develop a novel connection method for e-textiles that improves mechanical reliability and user experience.
• To replace galvanic connections with inductively coupled coils for power and data transfer.

Main Methods:

• Utilized two pairs of inductively coupled coils to transmit power and bidirectional data across air gaps.
• Designed and analyzed a compensation network for the inductive link.
• Explored the system's sensitivity to varying environmental conditions.
• Developed a self-tuning mechanism based on current-voltage phase relationships.

Main Results:

• Demonstrated continuous power and bidirectional data transmission across millimeter-scale air gaps.
• Achieved a data transfer rate of 8.5 kbit/s with 62 mW DC power output in the proof-of-principle.
• Hardware demonstrated capability for data rates up to 240 kbit/s.
• The system exhibited self-tuning capabilities.

Conclusions:

• Inductively coupled coils offer a mechanically reliable and user-friendly alternative to galvanic connections in e-textiles.
• The proposed double inductive link system significantly improves upon previous e-textile connection designs.
• This approach enables robust integration of flexible electronics with rigid components.