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Conventional bulky and rigid electronics prevents compliant interfacing with soft human skin for health monitoring and human-machine interaction, due to the incompatible mechanical characteristics. To overcome the limitations, soft skin-mountable electronics with superior mechanical softness, flexibility, and stretchability provides an effective platform for intimate interaction with humans. In addition, soft electronics offers comfortability when worn on the soft, curvilinear, and dynamic human skin. In this review, recent advances in soft electronics as health monitors and human-machine interfaces (HMIs) are briefly discussed. Strategies to achieve softness in soft electronics including structural designs, material innovations, and approaches to optimize the interface between human skin and soft electronics are briefly reviewed. Characteristics and performances of soft electronic devices for health monitoring, including temperature sensors, pressure sensors for pulse monitoring, pulse oximeters, electrophysiological sensors, and sweat sensors, exemplify their wide range of utility. Furthermore, we review the soft devices for prosthetic limb, household object, mobile machine, and virtual object control to highlight the current and potential implementations of soft electronics for a broad range of HMI applications. This review concludes with a discussion on the current limitations and future opportunities of soft skin-mountable electronics.
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Wireless sensors for continuous, multimodal measurements at the skin interface with lower limb prostheses
Precise form-fitting of prosthetic sockets is important for the comfort and well-being of persons with limb amputations. Capabilities for continuous monitoring of pressure and temperature at the skin-prosthesis interface can be valuable in the fitting process and in monitoring for the development of dangerous regions of increased pressure and temperature as limb volume changes during daily activities. Conventional pressure transducers and temperature sensors cannot provide comfortable, irritation-free measurements because of their relatively rigid construction and requirements for wired interfaces to external data acquisition hardware. Here, we introduce a millimeter-scale pressure sensor that adopts a soft, three-dimensional design that integrates into a thin, flexible battery-free, wireless platform with a built-in temperature sensor to allow operation in a noninvasive, imperceptible fashion directly at the skin-prosthesis interface. The sensor system mounts on the surface of the skin of the residual limb, in single or multiple locations of interest. A wireless reader module attached to the outside of the prosthetic socket wirelessly provides power to the sensor and wirelessly receives data from it, for continuous long-range transmission to a standard consumer electronic device such as a smartphone or tablet computer. Characterization of both the sensor and the system, together with theoretical analysis of the key responses, illustrates linear, accurate responses and the ability to address the entire range of relevant pressures and to capture skin temperature accurately, both in a continuous mode. Clinical application in two prosthesis users demonstrates the functionality and feasibility of this soft, wireless system.
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- Award ID(s):
- 1635443
- PAR ID:
- 10206074
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science Translational Medicine
- Volume:
- 12
- Issue:
- 574
- ISSN:
- 1946-6234
- Page Range / eLocation ID:
- Article No. eabc4327
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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