Force Sensitive And Photosensitive Electronic Skin Research Based On Graphene Materials

Intelligentization is an important direction for the development of Internet of Things technology,and the sensing of robot is a very important part of this technology.Pressure sensor,a key part to realize the intelligent robot sensing,is an important factor in electronic skin.The detection of haptic signals must meet the requirements of high sensitivity and adapt to complex application scenarios.Flexible tactile sensors have received extensive attention in the fields of intelligent manufacturing,medical health,and human-computer interaction,but due to the problems such as low sensitivity,high cost,complicated manufacturing process,and poor stability in the current research,flexible tactile sensors still face enormous challenges in market applications.Focusing on the challenges in recent years,this paper studied the periormanee improvement by micro-nano structure design and material optimization on the sensitivity and stability of flexible electronic skin.This paper first discussed the achievements and challenges of flexible electronic skin research,expounded the background and research significance of flexible tactile sensing,and proposed a pressure sensor with pyramidal graphene nanowalls electrode encased in composite dielectric film.Subsequently,the graphene electrode was characterized by micromorphology,and the influence of micro-nano structure on the surface of the electrode on the sensitivity of the sensor was studied.Then,according to the structural characteristies of the capacitive tactile sensor and combined with the multi-functional detection requirements of the tactile sensor,the composite zinc oxide flexible dielectric layer on the graphene electrode surface was designed and prepared,and finally the capacitive flexible sensor sample was fabricated.Subsequently,the finite element analysis and experimental results verify the improvement of the sensitivity of the composite dielectric layer to the capacitive touch sensor.Through static and dynamic measurements of the sensor,it is verified that the micro-nano structure design and material selection improve the sensitivity and stability of the device.The test results show that the flexible capacitive pressure sensor designed in this paper can realize high sensitivity pressure detection due to its micro-nano pyramid structure electrode and conformal composite dielectric layer.Our sensors have shown superior performance owing to the zinc oxide conformal composite dielectric layer with piezoelectric properties in a broad sensing range from a few pascals up to 22 kPa.Our sensors have a fast response time witihin 25 ms and a low operating voltage of 0.03 V.A super high sensitivity of 13.45 kPa-1 is observed under 440 Pa.The sensor can keep its original performance after more than 2000 compressions and 1000 bending deformations,and has good mechanical and electrical stability.In addition,the tactile sensor designed in this paper can respond to ultraviolet light,further expanding the functional diversity of the tactile sensor.Based on the highly sensitive tactile sensor,the application of flexible electronic skin will experience further development.The flexible electronic skin made in this paper can be combined with the robot to image the rough plane.This pressure sensor gives the robot the ability to detect braille and the ability to detect weak mechanics signals such as human pulse.The capacitive flexible electronie skin designed in this paper has a broad application prospect in biological medicine,industrial manufacturing,artificial intelligence and other fields due to its characteristics of ultra.high sensitivity,large measurement range,short response time,good mechanical and electrical stability.