Capacitance-based sensor design and application in automatic system

A capacitance-based sensor is presented to be a detector for particular automatic system in this paper. Firstly, sensing principle of the designed sensor is introduced. Then, three types of capacitance sensor in different shapes are designed and compared. the parameters affecting the sensor performance and sensitivities are discussed. Thirdly, the electric distribution and the fringe capacitance of sensors are simulated by software, and then the optimum excitation frequency of designed sensor is determined by analysis of practical measurements. At the last, the error of system is considered and analyzed. The experimental results show the feasibility of the designed capacitance sensors used for particular automatic systems.