Our TFSLOT sensor is an airspeed sensor designed to use on UAVs. Due to 3D printed case it is possible to optimize the characteristics according to the location of sensor on UAV and specific application. First use of this sensor is on ThunderFly autogyro TF-G2.
TFSLOT is commercially available from ThunderFly s.r.o., write an email to info@thunderfly.cz or shop at Tindie store.
In contrast to classical Pitot tube, the TFSLOT design is perfect choice for low airspeed measurement (generally bellow 10 m/s). The design has the following advantages compared to a pitot-probe:
- Better resolution on low airspeeds
- Less tendency to clogging
- Direct differential pressure sensor integration without any additional tubing.
TFSLOT is equipped with TFASPDIMU electronics, which contains the required differential pressure sensor and an IMU unit through which the pressure sensor is connected. To activate I2C access to it, it is necessary to set the pass-through mode in the IMU unit. PX4 is able to do it. All you have to do is add the following two lines to the startup configuration file on the SD card.
icm20948_i2c_passthrough start -X -b 2 -a 0x68
sdp3x_airspeed start -X -b 2
The script assumes a connection to port I2C-2. This can be changed with the -b parameter in both commands.
This approach requires firmware with modifications from the tf/aspdimu branch. In the future, we expect merging with upstream.