A LiDAR sensor three-dimensionally scans laser light outward of the vehicle and receives reflected light. A LiDAR data analyzer groups three-dimensional points of the reflected light acquired by the LiDAR sensor into clusters. A precise docking control start determination unit compares shapes and reflectance distributions between at least one of the clusters obtained by the LiDAR data analyzer and a reference cluster representing a stop target to determine whether or not the at least one cluster includes the stop target.