Position sensing for a bio-inspired flapping wing-actuation system

Abstract

Three sensors were investigated as possible position sensors for a 3 degree-of-freedom flapping wing-actuation system - infrared displacement sensor, infrared camera tracking system and resistive flex sensor. The performance of the sensors were weighed against such criteria as precision, sampling frequency, invasiveness and the scalability of the sensor to smaller Micro Air Vehicle systems. The IR displacement sensor and IR camera tracking system were ruled out as potential sensors. The IR displacement sensor had a precision of 1mm making it too imprecise. The IR camera tracking system had a limited sampling frequency of 22Hz. In addition, both these concepts were not scalable to MAV sizes due to their complexity. The flex sensor is suitable as a position sensor due to its high precision of 0.25mm. It is an analogue sensor and has a sampling frequency only limited by the data-logger and frequency response. Frequency and thermal characteristics were acceptable. Additionally, its solid state nature makes it highly scalable.