Research On MXene-based Sensor For Human Motion Detection

Human body movement signals include small range of movement signals such as eye movements and pulses,and large range of movement signals such as body flexion and arm extension.The detection and analysis of human motion signals is very meaningful.For example,the detection and analysis of human pulse motion signals can help doctors understand the health status of patients.The detection method of motion signal of human body by fitting sensor is widely used because of its low cost and good detection stability.but the existing sensor devices are large in size,not flexible,and unable to meet the motion signal detection of complex curved surfaces.In recent years,the technology of two-dimensional materials have made tremendous progress.Flexible sensors based on two-dimensional materials provide solutions for the detection of human motion signals.As a new member of the two-dimensional material family,MXene has a large specific surface area,high conductivity and strong mechanical properties,so that the flexible sensor based on MXene can also be used in the field of human motion signal detection.However,in terms of material preparation,the preparation method of MXene material needs to be improved due to its danger.In terms of device performance,whether the detected signals can provide sufficiently effective information still needs further verification.The main research work of this paper is as follows:(1)Material preparation: The preparation process of MXene prepared by hydrofluoric acid(HF)etching MAX phase materials was optimized.By adjusting the experimental parameters of material preparation,the most suitable synthesis method of MXene materials was obtained,that is,the chemical reaction is carried out for 24 hours under the condition of40?.On the other hand,a material preparation method with multiple etchings is proposed to reduce the risk of the experiment.(2)Fabrication of Sensor and performance testing: By using the vacuum filtration method to prepare the sensor network and the spin coating method to prepare the PDMS substrate,a flexible and stretchable piezoresistive flexible pressure sensor based on MXenewas constructed.The sensor has a high sensitivity(GF: 82.1),a faster response speed(124 ms)and good cycle working stability(4000 times).(3)Application test: We explored the application of MXene-based flexible sensors in human motion signal detection.In the detection of small-range motion signals,the sensor is tested for the detection of neck motion signals caused by human throat pronunciation.In the detection of large-range motion signals,the sensor is tested for motion signals of the finger joints and elbow joints.In addition,this part explores whether the detection data of the neck motion signal can provide enough effective information,and a large amount of data is combined with the deep learning network to realize the classification and recognition of human speech content,and the recognition accuracy of long vowels and short vowels are70.0% and 76.7%,respectively.