Yang Haitao, Xiao Xiao, Li Zhipeng, Li Kerui, Cheng Nicholas, Li Shuo, Low Jin Huat, Jing Lin, Fu Xuemei, Achavananthadith Sippanat, Low Fanzhe, Wang Qian, Yeh Po-Len, Ren Hongliang, Ho John S, Yeow Chen-Hua, Chen Po-Yen
Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117585.
Department of Biomedical Engineering, National University of Singapore, Singapore 117583.
ACS Nano. 2020 Sep 22;14(9):11860-11875. doi: 10.1021/acsnano.0c04730. Epub 2020 Aug 19.
Emerging soft exoskeletons pose urgent needs for high-performance strain sensors with tunable linear working windows to achieve a high-precision control loop. Still, the state-of-the-art strain sensors require further advances to simultaneously satisfy multiple sensing parameters, including high sensitivity, reliable linearity, and tunable strain ranges. Besides, a wireless sensing system is highly desired to enable facile monitoring of soft exoskeleton in real time, but is rarely investigated. Herein, wireless TiCT MXene strain sensing systems were fabricated by developing hierarchical morphologies on piezoresistive layers and incorporating regulatory resistors into circuit designs as well as integrating the sensing circuit with near-field communication (NFC) technology. The wireless MXene sensor system can simultaneously achieve an ultrahigh sensitivity (gauge factor ≥ 14,000) and reliable linearity ( ≈ 0.99) within multiple user-designated high-strain working windows (130% to ≥900%). Additionally, the wireless sensing system can collectively monitor the multisegment exoskeleton actuations through a single database channel, largely reducing the data processing loading. We finally integrate the wireless, battery-free MXene e-skin with various soft exoskeletons to monitor the complex actuations that assist hand/leg rehabilitation.
新兴的柔性外骨骼对具有可调线性工作窗口的高性能应变传感器提出了迫切需求，以实现高精度控制回路。然而，目前的应变传感器仍需进一步改进，以同时满足多个传感参数，包括高灵敏度、可靠的线性度和可调应变范围。此外，人们非常希望有一个无线传感系统，以便能够方便地实时监测柔性外骨骼，但这方面的研究很少。在此，通过在压阻层上开发分级形态、在电路设计中加入调节电阻以及将传感电路与近场通信（NFC）技术集成，制造了无线TiCT MXene应变传感系统。该无线MXene传感器系统能够在多个用户指定的高应变工作窗口（130%至≥900%）内同时实现超高灵敏度（应变系数≥14,000）和可靠的线性度（≈0.99）。此外，该无线传感系统可以通过单个数据库通道集体监测多段外骨骼的驱动，大大减少了数据处理负担。我们最终将无线、无电池的MXene电子皮肤与各种柔性外骨骼集成，以监测辅助手部/腿部康复的复杂驱动。
