Research On Manufacturing Technology Of Flexible Optical Fiber Pressure Sensor For Contact Force Detection

Since the society entered the information age,the Internet of Things and smart terminals have developed rapidly,and people's collection of information about the surrounding environment has been increasing in depth and breadth.As an important device for information collection,flexible pressure sensor is light and portable,and can obtain pressure information on irregular surfaces.It is widely used in the fields of robots,wearable electronic devices,human-computer interaction and smart skins,and has brought revolutionary changes to all walks of life.Flexible pressure sensors have become a research hotspot in recent years.Although relevant research continues to deepen,it is still a big challenge to realize a flexible pressure sensor with a large area,low cost,and simple process.Therefore,it is of great significance to prepare flexible strain sensors with high sensitivity,high flexibility,good repeatability,low cost and simple structure.As a new sensing and monitoring technology,optical fiber sensing technology has the advantages of long transmission distance,antiinterference and relatively strong corrosion resistance,etc.Compared with flexible pressure sensors such as capacitive and resistive sensors,it is easier to use optical fiber as the sensing element to achieve large-area distribution measurement,and the optical fiber has light weight and good flexibility,which can bring new breakthroughs to the research of flexible pressure sensors.Based on the optical fiber sensing principle of back-to-Rayleigh scattering,a flexible optical fiber pressure sensor for contact force detection is designed in the paper.It is proposed that single-mode fiber is used as the sensing element and polymer PDMS is used as the packaging material.In order to improve the sensitivity of the sensor,four different sensor structures are designed.The structure of the flexible pressure sensor is analyzed theoretically,and the relationship between pressure and fiber strain is clarified.The simulation analysis of the different packaging structures is carried out by using ABAQUS simulation software,and the rationality of the theoretical analysis is verified.The self-built test platform was used to carry out corresponding static performance tests on PDMS packaged sensors of different structures,sizes and ratios,and it was concluded that in the pressure range of 0?160k Pa,the fiber pressure sensitivity is preferably sponge structure,which can reach 4.06336??/k Pa.And the structure has good linearity and repeatability,small hysteresis,and has the ability to resist electromagnetic interference.Finally,explore the application of the sensor,attach the prepared flexible optical fiber pressure sensor to the mouse and the sole to detect the force of clicking the mouse and monitor the pressure distribution of the sole.In a self-made underwater simulation environment,use a flexible optical fiber pressure sensor to detect underwater pressure.The test results show that the flexible optical fiber pressure sensor can monitor the size and distribution of contact force in real time.The flexible piezoelectric sensor prepared in this paper has the advantages of simple preparation process,low cost and high sensitivity,it has great potential in smart wear,medical detection,monitoring of the surface pressure of underwater arc-shaped objects and so on.