Directional Wind Meter Using Differential Pressure Sensor
Imagine you are model aircraft pilot and for a perfect start you need to know the actual weather conditions, especially the speed and direction of the wind. With this information, you can reduce the risk to crash at the start and you can decide for the ideal orientation into the wind for a take off. There are anemometers like in figure 1 which give an indication about the windspeed and by turning it manually, the direction can roughly estimated. But this gives just a snippet of the actual conditions. A more robust and reliable system would be preferable.
Other devices on the market like vane style anemometer, see figure 2, or ultrasonic anemometers can be used to determine the speed and direction more precisely. But those systems have some disadvantages. They are quite expensive compared to the handheld anemometer and they are bulkier. An alternative, which is comparable in size and prize to handheld wind meters is needed.
As already known from Pitot tube applications, a differential pressure sensor like the SDP3x can be used to measure wind speed. Compared to other measurement principles like membranes this has the advantage that the sensitivity is higher at lower speed and thus is very accurate at small wind speeds. The excellent sensitivity of the SDP3x results from its thermal measurement principle as opposed to the diaphragm of conventional differential pressure sensors. To convert the SDP3x differential pressure output to a wind speed value, a conversion factor needs to be added to the standard pitot tube formula.
On Sensirion’s developer website we published tutorials, implementation instructions as well as sample code allowing you to build your own pitot tube including a SDP3x differential pressure sensor. Get inspired by visiting developer.sensirion.com/windmeter.