Optical Flow sensors are useful for maintaining drone position without GPS. Suitable for indoor and low altitudes where GPS signals are not reliable. This flow sensor also includes a lidar sensor for altitude detection.
This sensor works the same way as an optical mouse, helping your iNAV quad maintain position without GPS! It has a working range of up to 2m, and uses a VL53L0X Lidar rangefinder along with a PMW3901 optic flow module. The sensor is connected to your flight controller via a UART.