Multimodal Sensors with Decoupled Sensing Mechanisms

Abstract

Highly sensitive and multimodal sensors have recently emerged for a wide range of applications, including epidermal electronics, robotics, health‐monitoring devices and human–machine interfaces. However, cross‐sensitivity prevents accurate measurements of the target input signals when a multiple of them are simultaneously present. Therefore, the selection of the multifunctional materials and the design of the sensor structures play a significant role in multimodal sensors with decoupled sensing mechanisms. Hence, this review article introduces varying methods to decouple different input signals for realizing truly multimodal sensors. Early efforts explore different outputs to distinguish the corresponding input signals applied to the sensor in sequence. Next, this study discusses the methods for the suppression of the interference, signal correction, and various decoupling strategies based on different outputs to simultaneously detect multiple inputs. The recent insights into the materials' properties, structure effects, and sensing mechanisms in recognition of different input signals are highlighted. The presence of the various decoupling methods also helps avoid the use of complicated signal processing steps and allows multimodal sensors with high accuracy for applications in bioelectronics, robotics, and human–machine interfaces. Finally, current challenges and potential opportunities are discussed in order to motivate future technological breakthroughs.

Wearable Pressure Sensor Array with Layer-by-Layer Assembled MXene Nanosheets/Ag Nanoflowers for Motion Monitoring and Human–Machine Interfaces

“…Cheng and co-workers proposed a method to directly fabricate electronic devices on freeform surfaces using intense pulsed light-induced mass transfer, and deploying functional circuits on 3D freeform surfaces has greatly promoted the development of flexible wearable devices . Moreover, the functions of flexible wearable sensors are increasingly rich, and many flexible sensors for multi-modal detection have been developed . For example, Yang and co-workers reported a flexible sensor for underwater motion monitoring that simultaneously detects strain and temperature .…”

“…5 Moreover, the functions of flexible wearable sensors are increasingly rich, and many flexible sensors for multi-modal detection have been developed. 6 For example, Yang and coworkers reported a flexible sensor for underwater motion monitoring that simultaneously detects strain and temperature. 7 Therefore, the development of high-performance and multifunctional flexible pressure sensors is imminent.…”

Dielectrostriction Effect in Flexible Dielectric Realized by Ordered Doping of Iron Nanoparticles for Wide-Range Pressure Detection

“…They have been extensively investigated in recent years, and tremendous amounts of research results have been reported all over the world. 17 For example, low-cost pressure sensors based on MXene nanosheets and papers are reported by Fu et al 18 and Gao et al 19 Multimodal sensors with decoupled sensing mechanisms are reported by Shin et al 20 and Yang et al 21 According to the sensing mechanism, they could be primarily classified into the resistive type and the capacitive type. 22 Resistive pressure sensors have the advantages of high sensitivity, large linear working range, and good response stability synchronously.…”

A multimodal sensing CMOS imager based on dual-focus imaging

“…[6] Despite some progress, existing multimodal sensing technologies assemble various sensors based on different sensing principles, resulting in bulky system designs, cumbersome signal interfaces, and complex data processing procedures. [7] These technologies cannot meet the growing complex environment perception demands of miniaturized devices, such as microrobots [8] and in vivo medical devices. [9] Thus, a miniature multimodal sensing platform is urgently needed.…”