A Flexible Microfluidic Sensor For Aerodynamic Pressure Measurement

A flexible microfluidic sensor for aircraft aerodynamic pressure measurement is developed in this paper.The sensor,consisting of three parts:a flexible material with a cavity,a conductive liquid,and an electrode,can measure the surface aerodynamic pressure of the aircraft structure during the wind tunnel experiment and the flight process.Because of its small size,large deformation survivability,simple measurement system,and high sensitivity,the developed sensor will provide a basis for the sensor network integrated on the surface of the deformable aircraft,and reduce the influence of the sensor network on the measurement,and ultimately achieve the improvement of flight performance.In this paper,in the design process of existing microfluidic sensors,the combine of the utilizing of the capillary force between the conductive liquid and the flexible substrate and the design of "main channel-branch channel" design inside the sensor flexible material is innovative.Besides the amount of change of the percentage of the sensor resistance output is amplify.Through soft lithography technology and structural design and selection of different materials,this paper finally realized the manufacture of sensors and tested them under different gas pressures.The flexible microfluidic pressure sensor in this paper can change its initial resistance percentage up to 25%under the gas pressure of about 270kPa.The thickness of the sensor is 0.75mm and it is easy to realize the fitting with the curved surface and withstand large deformation.Although the sensor performs weakly at low pressure,and has a large hysteresis.In the process of implementation provides a certain reference to the problems that may be encountered in constraining microfluidic,deformation of the microfluidic in the substrate under external pressure,or the miniaturization and networking of the sensors.