Arduino based ultrasonic anemometer

Anemometer is a fancy name of a device which measures wind speed and direction. We are used to see mechanical spinning devices that rotate and thus indicate speed strength and direction. As we know, mechanical things aren’t always reliable especially in rough conditions. In other hand, ultrasonic anemometer can be more sensitive and precise. Lfaessler have written a series of build posts of ultrasonic wind meter. His design uses four pairs of ultrasonic transducers that are positioned perpendicularly. By knowing ultrasound speed in the air, it is possible to determine wind speed and direction from ultrasound speed change. All four transducers are controlled by Arduino which takes care of correct signal routing and measuring time between sent and received signals. Arduino also calculates wind direction in 2D plane and its speed. Since received ultrasonic signal is weak, he designed amplifier to make them acceptable for Arduino input. There are intense testing and tuning involved in this part, since it is important to sense received signals correctly in order to get precise readings. After initial testing and build, project ended in… Continue reading

Wind Indicator

Every other person has some fantasy towards weather. They really like to be updated about the weather very frequently. The author of the project was one of the same kind of person. The author of the project designed a LED based Wind indicator which displays the wind direction, its force and a prediction for the next day. Since the project is still in the developing mode, the data which the wind indicator has to be connected to the PC using a USB to serial interface. If your PC has a serial port unlike a laptop, you can directly hook up a serial cable instead of using the converter. For the project all you need are LED’s, resistors, buttons, screw terminals, Atmega, its ISP programmer and python v2.6. The project has been build using SMD based components, however if you wish to you can make it using through hole components. The code is ready to burn as it’s included with a hex file. The user used the weather data available on the internet and using python transferred it to the microcontroller. Continue reading