chore: fix central to center

Signed-off-by: vividf <yihsiang.fang@tier4.jp>

calibrators/marker_radar_lidar_calibrator/README.md

@@ -10,7 +10,7 @@ Currently, the calibrator only supports radars whose detection interface include
 
 ## Inner-workings / Algorithms
 
-The calibrator is designed to estimate the transformation between radar and lidar sensors. It starts by pinpointing the central points of reflectors within lidar pointclouds and radar objects, then aligns these points for precise matching. An SVD-based and a yaw-only rotation estimation algorithm are applied to these matched points to estimate the transformation.
+The calibrator is designed to estimate the transformation between radar and lidar sensors. It starts by pinpointing the center points of reflectors within lidar pointclouds and radar objects and then aligns these points for precise matching. An SVD-based and a yaw-only rotation estimation algorithm are applied to these matched points to estimate the transformation.
 
 Specifically, the calibration process consists of four primary steps: constructing a background model, extracting the foreground to detect reflectors, matching and filtering lidar and radar detections, and finally estimating rigid transformation.