A Flexible Three-axial Capacitive Tactile Sensor With Dielectric Multilayer

To solve the flexibility of three-axial tactile sensor, three-axial force detection and the compatibility of sensor array, a flexible three-axial capacitive tactile sensor with dielectric multilayer was researched in this thesis.Start from the one dimensional flexible tactile sensor with dielectric multilayer (PDMS layer and air layer), the working principle of this type of sensor was analyzed in detail. Combining with theory analysis, experiment and simulation, the relatedness between the sensor’s output characteristic and the type of the conductive particles filled in dielectric multilayer and the height ratio of the different dielectric layer was studied, and the effect of these sensitive parameters on the sensor’s output characteristic was found.The electrodes for the flexible three-axial capacitive tactile sensor were designed based on the uniplanar multi-electrodes. The simulation results are integrated with the evidence theory to make clear of the electric field sensors work area, which is helpful in designing the reasonable structure of electrodes and shielding electrodes. The relationship between the change of dielectric coefficient and the applied force is studied, when the dielectric multilayer is deformed under applied force. The influence rules and characteristic relation between the applied force and each direction of capacitances in the unit are explored to build the analytical model. The output characteristic of sensor is optimized by the PDMS layer filled with MWCNTs and adjusting the height ratio between PDMS layer and air layer. The calibration experiment of three-axial tactile sensor has been done to get the mathematical model of the sensor. The experiment results show that the three-axial tactile sensor has the characteristics of simple preparation technology and strong practicability, which can be widely used in sports training, medical rehabilitation, etc.