Bio-inspired wind frame state sensing and estimation for MAV applications

Kapton strain-based hair sensors were designed and fabricated to measure flow on a micro air vehicle. The fabrication process is carried out using a single mask and a combination of cleanroom and regular lab room processing. The processing resulted in successful realization of 6.4 mm long sensors with high yield. Associated signal conditioning circuitry was developed to extract small variations in resistance due to flow while suppressing noise. Three sensors were deployed on a fuselage shaped structure and characterized in a wind tunnel. Static linear and nonlinear estimation schemes were obtained based on the characterization data to determine the angle of attack, sideslip angle and airspeed values. For small angles of perturbation, the estimation scheme demonstrated good accuracy in determining the variables of interest. The sensors along with the signal conditioning circuitry are sufficiently lightweight that they can be used for estimating velocity states on micro air vehicles.