Herren, BlakeWebster, VincentDavidson, EricSaha, Mrinal C.Altan, M. CengizLiu, Yingtao2022-03-212022-03-212021-07-01Herren B, Webster V, Davidson E, Saha MC, Altan MC, Liu Y. PDMS Sponges with Embedded Carbon Nanotubes as Piezoresistive Sensors for Human Motion Detection. Nanomaterials. 2021; 11(7):1740. https://doi.org/10.3390/nano11071740https://hdl.handle.net/11244/335052Porous piezoresistive sensors offer promising flexible sensing functionality, such as human joint motion detection and gesture identification. Herein, a facile fabrication method is developed using a microwave-based rapid porogen removal technique for the manufacturing of porous nanocomposite sponges consisting of polydimethylsiloxane (PDMS) and well-dispersed carbon nanotubes (CNTs). The porogen amounts and CNT loadings are varied to tailor the porosity and electrical properties of the porous sensors. The sponges are characterized by a scanning electron microscope (SEM) to compare their microstructures, validate the high-quality CNT dispersion, and confirm the successful nanofiller embedding within the elastomeric matrix. Sponges with a 3 wt% CNT loading demonstrate the highest piezoresistive sensitivity. Experimental characterization shows that the sponges with low porosity have long durability and minimal strain rate dependence. Additionally, the developed sponges with 3 wt% CNTs are employed for the human motion detection using piezoresistive method. One experiment includes fingertip compression measurements on a prosthetic hand. Moreover, the sensors are attached to the chest, elbow, and knee of a user to detect breathing, running, walking, joint bending, and throwing motions.Attribution 4.0 InternationalPiezoresistive sensorWearable electronicsNanocomposite spongeHuman motion monitoringSemiconductorsCarbon nanotubesElastomersFlexible sensorsArticle10.3390/nano11071740