Lighthouse positioning, drone positioning system

The drone positioning system uses vivo Lighthouse v1 base stations for location positioning with millimeter-level accuracy and a refresh rate of over 30Hz.
Bootloader
: https://github.com/bitcraze/lighthouse-bootloader
Firemare:
https://github.com/bitcraze/lighthouse-fpga
Data analysis: Synchronization frame
clock frequency: 24MHz
, with 60 frames per second for X and Y axis scanning. With two base stations synchronized, any base station will leave a blank frame. After the other base station flashes, it rotates and scans along the X-axis, then flashes again, and rotates and scans along the Y-axis.
Time difference: Scan time - flash time, allowing the calculation of the base station's X and Y axis angles.
Sensor time difference: Given the rotation speed (60Hz) and sensor distance, the rotation radius can be calculated, allowing conversion to a positional coordinate system
. Lighthouse v2 can be used to achieve positioning with more than two base stations (see documentation)
 
 
. Two Lighthouse v1 base stations were used for positioning, and calibration results were obtained
 
. The sensor spacing is between 7.5-15mm, and the calibration results show that the spacing error of each sensor is less than 1mm. The actual positioning error is within the range of mm, so the spatial position can be calculated.
 
The video shows that the positioning effect is quite good; the positions of all four sensors are calibrated and displayed accurately.
 
(Bilibili)