Wirelessly controlled harvester/sensor of air speed

A wirelessly controlled self-powered multi-functional system that uses a relay to change from harvesting air flow energy to sensing its speed and vice versa is developed. Both functions are achieved through the use of the same micro-wind turbine. When the relay is in the on position, the turbine harvests the air’s kinetic energy to charge a battery. When a measurement is needed, the relay is turned off wirelessly and energy harvesting is shut down. The charged battery is then used to turn on a wirelessly controlled single board computer that controls a data acquisition system to sense the rotational speed of the turbine, which is proportional to the air speed. The system is tested and results from a broad range of wind speeds are presented and analyzed. The system presented here can be used for autonomous sensing of air speed without a need for wired connections to an external power source or batteries that need to be regularly replaced, which makes it ideal for integration within the Internet of things as a platform for a smart building system.