The modified airspeed tube is a digital differential pressure sensor, I2C communication, suitable for PIXHAWK PX4. Unlike the analog differential pressure sensor used by APM, APM is not universal. Please pay attention when purchasing.

Airspeed meter calibration introduction: http://plane.ardupilot.com/wiki/calibrating-an-airspeed-sensor/

Electronic equipment is a product with high technical content. When your equipment fails, please carefully check the power supply voltage of the line. The imported module burned in use after the sale is not covered by the warranty.

Check operation

You can use APM Planner or other ground stations to read the airspeed count value. Blow into the pitot tube and observe the response. Zero and small oscillations (2-3) are normal in still air. The airspeed changes with the square root of the pressure, so the change at close to zero pressure difference is very small, and a larger pressure change is required to produce the estimated speed change during flight. If you see mostly 0, 1, 2, and occasionally bounce to 3 or 4, consider it normal. You will not see such changes while flying.

Sensor: the upper port is dynamic pressure, the lower port is static pressure

ARSPD_BUS set as 0,use internal I2C

ARSPD_SKIP_CAL set as 0, each time restart the flight controller, need to calibrate the airspeed meter offset. Set to 1, automatically skip the airspeed gauge offset calibration, using the last calibrated offset

ARSPD_TUBE_ORDER set as 2,Automatic matching of the upper or lower tube is dynamic pressure

ARSPD_TYPE set as 1, use I2C-MS4525D0

In the ground station debugging interface, observe the change of the airspeed meter. The general value jump is 1-3 in the normal range. Blow air to the airspeed meter. If the airspeed value increases, the airspeed meter works normally.

Color (Airspeed) Pixhawk Red +5V in +SV out Green SCL SCL Yellow SDA SDA Black GND G