ROBART II is a battery powered autonomous sentry robot used by the Naval Ocean Systems Center in San Diego as a testbed in the research areas of environmental modeling and intelligent security assessment. An architecture of nine distributed microprocessors makes possible advanced control strategies and real-time data acquisition capability. Higher level functionality map generation, path planning, position estimation, obstacle avoidance and statistical security assessment is currently implemented by the Planner on an IBM-PCAT computer, using a radio link for communication with the Scheduler. Numerous sensors are incorporated into the system to yield appropriate information for use in collision avoidance, navigational planning, environmental awareness, assessing terrain traversability, and performing security related functions. Two separate drive motors provide for differential steering, allowing the robot to turn in place in order to maneuver in congested indoor environments. The entire unit is housed in a rugged plastic and fiberglass body, measuring 17 inches wide and 23 inches long at the base, and extending to a height of 50 inches. Special internal circuitry checkpoints are analyzed by self-diagnostic software, and operator assistance is requested if necessary through speech synthesis. Keywords Robotics Artificial intelligence.