Distributed Robot Agent Brent Dingle Marco A. Morales

Outline Definition of the problem A robot agent

Problem A robot is an Intelligent Connection of Perception to Action (Jones, Flynn 1993) Multiple sensors and actuators Two main approaches: –Sequential based –Behavior based

Sequential Based Approach Sensors gather data Data are translated into a intermediate language A model of the world is built Motion planning is performed Motion commands are translated into low level orders for actuators

Behavior based approach Modules generate behaviors Each has perception and planning Each receives input and give commands A mediator scheme assigns control to modules Basic behaviors lead to complex behaviors No central model of the world No central control

Robot Architecture

Components of the Robot Agent Planner –Finds a path between two points or reports no such a path Navigator –Creates a list of high level commands for the robot Pilot –Gives low level commands to the controller and it’s aware of the sensors Controller –Controls actuators in closed chains

Problems: Environment modeling –To model the environment the robot either is able to: Identify main features by itself, or Uses a set of preloaded features. –It seems reasonable to make the robot use both.

More Problems Distribution of tasks –Environments are far too complex for a robot to handle efficiently in detail –A robot shouldn’t care for parts of the environment that are far away, unless it really needs them. Nearby robots can help by providing info on the environment. Rooms, buildings, sites can help by having planning abilities.

Solution Build a distributed Motion Planning Agent Use nearby robots as sources of info for the environment Use precompiled info about the environment The local planner gathers info from all the robots in it and makes plans for them while they are nearby The robots can ask a local planner for a plan to follow The robots have the navigator, pilot and controller. A global planner coordinates the missions of the robots.

Distributed Planner Global planner Defines general goals based on main tasks –Go to room 124, go to room 302 Local planner Activated when the robot arrives to the area known to a given local planner Coordinates robot information with room information Stores a local map of the room and info gathered by all robots in the room Gives a plan to each robot in its “influence” area.

Robot agent Basic planner –Takes control when no info is given by a room planner Navigator Pilot Controller