When [Fab] needed anemometer in his latest project, he was troubled by the limited scope and relatively high price of commercial options. His solution is an impressive DIY anemometer that can be comparable to ready-made alternatives.
Anemosens is as ambitious as windiy_ A component of the 2 horizontal axis wind turbine is designed from the ground, but it is also suitable as part of a standard home weather station. The microcontroller unit uses RS485 / MODBUS connection to ensure that the data from the wind sensor can be accessed through various platforms. Serial streams through USB and SD cart slots can also be used to record data, which is particularly useful for long-term unsupervised monitoring. [Fab] also integrates an esp32 for recording data in the air.
MCU is also equipped with a location for the prestigious bme280, which is a relatively accurate temperature, pressure and humidity sensor, which is usually deployed in DIY weather station. This feels like a good touch, because it means that the anemometer package itself can be used as a basic weather sensing station or as a backup for more detailed environmental monitoring.
At present, the prototype uses Hall effect sensor to measure wind speed, and as5048b magnetic rotary encoder does quite well in measuring rotation (wind direction). Some calibration may be required to improve the accuracy of this setting, but this is a promising start.
[Fab] has identified some shortcomings of the bearing, but has a plan for future iterations. He might want to see this spare part anemometer, which uses an old hard drive bearing.