Force Transducer Through Total Internal Reflection and Frustrated Total Internal Reflection for a Three-Axis Anemometer

This paper introduces a method for measuring forces applied in a normal direction to the device using frustrated total internal reflection (FTIR) and infrared technology. Using FTIR for measuring force is not a new concept, but the past systems have used this principle by changing the material at the surface to change the refractive index at the point of contact. The design we propose causes a physical deformation to the waveguide, which causes changes in the output of the transducer. The transducer is designed to be implemented in a low cost three-axis anemometer for use in high-spatial resolution data gathering for wind generation stabilization. Our data supports the design of our transducer as it shows a correlation between the force and deformation of the upper surface of the waveguide and the output of the infrared phototransistor. The final section of the paper suggests a new design for a three-axis anemometer using the newly developed transducer.