Aerotenna US-D1 Radar Altimeter¶
The Aerotenna US-D1 Radar Altimeter has a range of 50m, an update rate of 82hz and weighs only 110g.
Warning
currently the manufacturer warns that operation indoors can be problematic due to multi-path reflections…caution is advised
The user manual for this radar unit can be found here

Note
Support for this sensor is available in Ardupilot firmware versions 4.0 and later
Connecting to the Autopilot¶
For a serial connection you can use any spare Serial/UART port. The example below shows how to connect to SERIAL4 as the first rangefinder.
- SERIAL4_PROTOCOL = 9 (Lidar)
- SERIAL4_BAUD = 38 (38400 baud)
- RNGFND1_TYPE = 11 (uLanding…this device’s name as a prototype)
- RNGFND1_MIN_CM = 50
- RNGFND1_MAX_CM = 4500
- RNGFND1_GNDCLEAR = 10 or more accurately the distance in centimetres from the range finder to the ground when the vehicle is landed. This value depends on how you have mounted the rangefinder.
Testing the sensor¶
Distances read by the sensor can be seen in the Mission Planner’s Flight Data screen’s Status tab. Look closely for “sonarrange”.
