  In this paper, we present a framework for self-localization of parking robots
in a parking lot innovatively using square-like landmarks, aiming to provide a
positioning solution with low cost but high accuracy. It utilizes square
structures common in parking lots such as pillars, corners or charging piles as
robust landmarks and deduces the global pose of the robot in conjunction with
an off-line map. The localization is performed in real-time via Particle Filter
using a single line scanning LiDAR as main sensor, an odometry as secondary
information sources. The system has been tested in a simulation environment
built in V-REP, the result of which demonstrates its positioning accuracy below
0.20 m and a corresponding heading error below 1{\deg}.
