Research On Intelligent Integrated Sensing Technology Based On Flexible Compound Mechanism

Flexible wearable sensors have attracted much attention due to their flexible and deformable characteristics.Flexible devices can be widely used in many fields such as human health monitoring,robot intelligent sensing,human-computer interaction,medical rehabilitation,and so on,and have good development prospects.The manufacturing process of flexible devices based on traditional integrated circuits has been developed and mature,but due to its high manufacturing cost and strict requirements on materials,the application of this process in the field of manufacturing flexible devices is limited.At present,a variety of new flexible device preparation processes have been developed,such as screen printing,spray-coating,and electrostatic spinning.It has the advantages of simple preparation process,low cost and easy large-scale preparation,Moreover,the above-mentioned processes have relatively loose requirements for materials,which can stimulate the exploration of flexible devices in multiple sensing fields.However,most of the flexible sensors prepared based on the new micro-nano process have only one sensing function and are not suitable for the detection of abundant health signals and posture information of the human body.Therefore,the development of flexible sensor devices integrating sensors with different functions has gradually become an important research direction.In this study,we propose a flexible multi-functional sensor integrated with three working modules:strain-liquid water molecules-pressure sensing.It is mainly based on the working principles of interdigital capacitor and parallel plate capacitor,the interdigitated pattern thin electrode based on silver nanowires(Ag NWs)is fabricated on elastic polydimethylsiloxane(PDMS)substrate by spray-coating process that possess mass fabrication and low cost,and the silk fibroin serves as the dielectric that can sense liquid water molecules in the air.Strain sensing module(SSM)realizes the detection of tensile strain in two-dimensional X and Y axis through the change of the spacing of finger electrodes.Pressure sensing module(PSM)based on parallel plate capacitor structure can detect the maximum external pressure of 55 k Pa,and the maximum sensitivity reaches0.117 k Pa^-1.Furthermore,liquid water molecules sensing module(LWMSM)is mainly based on the previously reported unique selection of silk fibroin to absorb liquid water molecules in the air,and its capacitance can rise to 435.4%after 5 s of humidification.With the help of strain-liquid water molecules-pressure sensing,the multi-functional sensor can be used as human-computer interaction devices,and can also realize the perception of human breath monitoring and finger joint sensing.Therefore,this device has a wide range of applications in the field of flexible wearable sensing.