Fabrication of smooth-surfaced flexible thermal sensor for detecting wall shear stress

We newly proposed a novel type of smooth-surfaced flexible thermal shear stress sensor and developed a fabrication process based on a micro-machined PDMS structure and film transfer technology. The proposed sensor has the advantages that it can be placed on a curved streamlined surface of a vehicle and can measure the shear stress with a high degree of accuracy because of its smooth surface. The developed sensor was inserted into a tube with a diameter of 10 mm and was successfully fitted to the inside curved surface because of its flexibility. A response time value of 20 ms was obtained.