US Patent 9964559 Cross track error calculation from active light sensors

Disclosed is apparatus for determining cross track error between a stored planted location and the actual physical location of plants. An array of active light sensors is mounted on a vehicle for travel above the plants. The array of active light sensors generate an electrical signal from each sensor corresponding to the reflected light from the sensor. A computer system generates a reflectance curve from the array of sensors to determine the location of a plant below the array of sensors and also generates the cross track error.