Wearable flexible ultrasonic transducers: materials, applications, and challenges

Area of Science:

• Biomedical Engineering
• Materials Science
• Medical Devices

Background:

• Flexible Ultrasonic Transducers (FUTs) are emerging for wearable medical devices.
• They enable noninvasive, continuous monitoring on curved body surfaces.
• FUTs overcome rigid transducer limitations like poor conformability and wearability.

Purpose of the Study:

• To review the working principles and architectures of FUTs.
• To summarize key material systems used in FUTs.
• To highlight FUT applications and future challenges.

Main Methods:

• Review of existing literature on FUTs.
• Analysis of material systems including piezoelectric elements, substrates, electrodes, and encapsulation.
• Categorization of applications in diagnostics, treatment, and human-machine interaction.

Main Results:

• FUTs utilize advanced piezoelectric materials, stretchable electrodes, and soft layers.
• Key components include flexible substrates, piezoelectric elements, backing/matching layers, and electronics.
• Applications span diagnostics, therapy, healthcare accessibility, and human-machine interfaces.

Conclusions:

• FUTs offer significant potential for advanced wearable healthcare.
• Further research is needed for long-term performance, miniaturization, and wireless integration.
• Addressing array element localization is crucial for future development.