Towards a 3D printed acoustic sensor inspired by hair-like structures of insects: a study of hair shape and size

Over ages insects evolved to be smaller and more efficient with several miniature
sensing mechanisms reacting to the environment around them. The hair-like structures, called trichobothria or trichoid sensilla, are fascinating mechanisms that allow insects to react to airflow and low frequency, near field, sound. Nevertheless, it is thought that from this sensing structure, other sensing mechanisms are derived by a change on the hair structure. This includes sensing of odours, acceleration, touch, temperature, as well as a gyroscope-like mechanism. This project proposes the use of advanced 3D printing techniques to create a sensor inspired by the trichoid sensilla of insects. Inspiration comes, in particular, from the sensilla structure of the caterpillar Barathra brassicae, and one from the crickets previously studied in the EU CILIA project. The focus is on developing a mechanical structure that responds to sound. Arrays of sensors that react at different sound frequencies allow frequency content measurement of a sound without the need for computationally expensive digital processing techniques (DSP).