Optical flow and LIDAR-Lite
This page shows you how to set up the PX4Flow and a LIDAR-Lite for position estimation in the INAV position estimator. A short video demonstrating a position hold can be seen here:
The PX4Flow has to point towards the ground and can be connected using the I2C port on the pixhawk.
For the connection of the LIDAR-Lite please refer to this page.
For best performance make sure the PX4Flow is attached at a good position and is not exposed to vibration. (preferably on the down side of the quad-rotor).
All the parameters can be changed in QGroundControl
Set to 1 to enable lidar-lite distance measurements
Set to 1 to enable altitude estimation based on distance measurements
- INAV_FLOW_DIST_X and INAV_FLOW_DIST_Y
These two values (in meters) are used for yaw compensation.
The offset has to be measured according to the following figure:
In the above example the offset of the PX4Flow (red dot) would have a negative X offset and a negative Y offset.
Set a calibration offset for the lidar-lite in meters. The value will be added to the measured distance.
For advanced usage/development the following parameters can be changed as well. Do NOT change them if you do not know what you are doing!
Sets the weight for the flow estimation/update
Sets the threshold for altitude estimation/update in meters. If the correction term is bigger than this value, it will not be used for the update.