Temperature And Pressure Sensor Based On PEDOT:PSS-CNT And Plate Capacitor

As a sensor integrated array or system that simulates human skin functions,electronic skin can mimic human skin to achieve functions such as touch,pressure,slid and thermal sensation.It has the advantages of high sensitivity,good accuracy and flexibility.Health monitoring system and human-computer interaction interface have important application prospects.Flexible sensors that can be used in electronic skin to achieve functions such as touch,pressure,sleek,and thermal sensation have attracted great attention in recent years.These studies have focused on sensors with a single function,such as flexible tactile sensors,flexible thermal sensations.Sensors and flexible sliding sensors,etc.,there have less research on sensors with multiple functions.However,human skin can detect changes in temperature and pressure at the same time.Therefore,researching a sensor capable of simultaneously measuring temperature and pressure has extremely important practical significance and application value for advancing the development of electronic skin.To solve this problem,this paper proposes a temperature and pressure sensor based on PEDOT:PSS-CNT and plate capacitor,which can simulate human skin and simultaneously measure temperature and pressure.Aiming at the problem of multi-input and multi-output of the flexible temperature and pressure sensor,this paper studies and establishes the decoupling model of the temperature/pressure sensor,which will be very helpful to realize the practical application of the sensor.The sensor not only improves the shortcomings of the traditional sensor's flexibility,but also enables simultaneous measurement of temperature and pressure.Then,according to the material and size requirements of the electronic skin,combined with the measurement principle of the temperature and pressure sensor,research and select the manufacturing process suitable for temperature sensors and pressure sensors,the electrodes and substrate of the temperature sensor,the upper and lower plates?the upper and lower plate electrodes and the dielectric layer material of the pressure sensor are selected and prepared.The flexible temperature/pressure sensor has an overall size of 15×15(mm),the temperature sensor electrode has a size of 10×10(mm),and the pressure sensor upper and lower plate electrodes and the intermediate dielectric layer have a size of 10×10(mm).Finally,according to the structure of the designed temperature and pressure sensor,a complete flexible temperature and pressure sensor was prepared,and various characteristics of the sensor device were measured and analyzed through experiments.The experimental results show that the temperature of the flexible temperature sensor is negatively linearly related to the output resistance.The ratio of electrode material PEDOT:PSS to CNT has a great influence on the performance of the temperature sensor,while the pressure sensor has a good temperature stability.The output capacitance is positively linearly correlated to pressure across different ranges.Among them,the temperature sensor has a linearity of 3.91% in the range of 23? to 45?,a hysteresis of 1.84%,a repeatability of 5.08%,and a sensitivity of 0.41 ? /?.The input and output of the pressure sensor are linearly correlated in two ranges.The linearity is 2.39% at 0-180 mN,the sensitivity is 0.20%/mN,the linearity is 3.83% at 180-600 mN,the sensitivity is 0.0071%/mN,the repeatability of the pressure sensor is 0.03%,and the hysteresis is 10.69%.Finally,the experimental results verify the performance of the sensor when the temperature and pressure change simultaneously,and the relationship between temperature,pressure and output resistance is obtained.The results show that the temperature and pressure sensor can decouple the effect of pressure on temperature,and the presence of pressure does not affect the sensitivity of the temperature sensor to temperature.The above results show that the temperature and pressure sensor designed in this paper has the advantages of high sensitivity and good linearity,and the sensor has the function of accurately measuring temperature and pressure at the same time,and can well simulate the functions of human skin's touch pressure and temperature system.The sensor unit and the subsequent array of biomimetic electronic skin have important application prospects in the fields of robots,biological research,health monitoring systems and so on.