NEW!! I've added LDraw files for the robot and the bridge - See my Brickshelf directory!
This Mindstorms robot uses a light sensor to detect a hole in the ground, and deploys its own bridge to cross the gap. Drive unit is based off of the differential drive shown at the end of the RIS 2.0 manual.
Description of program operation:
(1) The robot senses a gap in the ground using the light sensor. (2) Robot deploys the bridge. (3) User manually disconnets the bridge. (4) User pushes bumper sensor. (5) Robot lifts deployment arms. (6) Robot crosses bridge. (7) Robot turns around in place. (8) Robot lowers deployment arms. (9) User manually connects the bridge. (10) User pushes bumper sensor. (11) Robot lifts bridge into storage position. (12) User pushes bumper sensor. (13) Robot continues on its way.
The bridge builder uses only parts available in RIS 2.0, but it may be dressed up by using crew cage from Rock Raiders: Chrome Crusher (#4970). Otherwise, use the bumper design shown in the differential drive shown at the end of the RIS 2.0 manual.