Object Finding

"The objective of the task is to build and program a Lego robot that navigates through a ``house'', looking for a particular object and retrieving it. The robot will start at the entrance to the main corridor, search through the different ``rooms'' for objects, and bring a particular object (a black golf ball) to the exit at the other end of the corridor. All operation has to be autonomous (i.e. once started there can be no more input to the robot). The figure below shows an example scenario."

"The different rooms and the hallway will be constructed on a rectangular 30.5 cm x 30.5 cm ( 1' x 1') grid. The maximum area will be 2.14 m x 2.14 m ( 7 x 7 cells) and all walls will be aligned with the cells of the grid. Therefore, all corners will be at 90° angles. The height of the walls will be between 11.5 cm and 12.75 cm (4.5" - 5").
The entrance will always be in the left upper corner and lead to a 30.5 cm (1 grid square) wide hallway that leads straight to the exit (which is always in the left bottom corner of the 7 x 7 grid). Rooms open up to the right of the hallway, can have arbitrary sizes, and can be connected to other rooms. Within the rooms will be two objects (one red and one black golf ball). Initially, these objects will be located in the center of one of the grid cells. In the beginning, each team can place their robot at an arbitrary position within the first grid square at the entrance (the contour of the robot can not fall within any other grid square of the ``house'').
House Materials:
The competition “house” will be constructed from plywood and will not be painted. The floor will be smooth, slightly textured, and without grid markings. It will be lightly colored."