This paper proposes small beacon devices named pebbles for a user to configure routing environment for autonomous robot navigation. Each pebble has infrared-based communication functionality to detect adjacent pebbles and share such adjacent information to construct a topological map for the environment. The robot can calculate the path to any location using the topological map and navigate by following pebbles' beacon signals. We discuss our proposed system from user interface aspect and show that it can be usable for non-expert home or office users. We also show the current implementation of the pebbles and the robot, and envision application services enabled by our proposed system.