The Examples of Applications of the Agent Systems - A Perspective on Agent Systems - page 95

task distribution among robots so that the realization of tasks would be performed in
the shortest possible time. The mobile robots system realizes its tasks as follows:

￿ The environment in which mobile robots operate is considered. Apart from the

robots there are also resources in the environment [166, 191].

￿ There is a specified number ( N ) of mobile robots operating in the system. All robots

are identical and may relocate in the environment. The environment in which the
robots exist allows for the relocation of robots and the specification of the distance
between two robots at a given moment. A certain limiting value of the distance
between the robots is established. For a given robot, the robots which are less than
the limiting value of distance away from each other are referred to as the neigh-
bouring robots. Among these robots certain relationships may take place, which
are unavailable the those non-neighbouring. It may be accepted that the neigh-
bouring robots may communicate directly. Due to the limiting value of distance
we may specify the range of the wireless communication between the robots.

￿ There are M tasks in the system. The robots have to realize these tasks. Each task

may be realized by one robot (which is given a task) and each robot is capable of
performing a task, but may realize only one task at a time.

￿ At the initial moment, only a certain initial number of tasks M i is revealed in the

system. On completion of the task, new tasks or revealed (generated) whose num-
ber is established randomly (within a certain range). The moment the number of
generated tasks reaches M no more tasks appear in the system.

￿

Tasks that appear after finishing the realization of a given task by a robot are
initially assigned to this robot. However, later they may be given to other robots.

One of the basic properties of this system is that when a given robot relocates
in space, a group of neighbouring robots, with which it has the direct connection,
changes. However, this robot has always connection with its agent A g 0 . The agents
of type A g 0 , inter alia, pay attention to the communicative integrity of the whole
group of robots.
The task of the agent system, which will be used for the management of a group
of mobile robots, is to distribute tasks in such a way so as to allow a group of mobile
robots to perform them in the shortest time. This task is in some sense similar to the
task of balancing the resources described in Chap. 4 .
Resource are tasks intended for robots to realize, however, their uniform distrib-
ution corresponds to the equal assignment of tasks to the robots. The agent system
consists of the following agents:

￿ The agents of type A g 0 are generated at the moment of activation of a given robot in

the system. There is only one instance of this agent for each robot, and every agent
is related to one particular robot it represents in the system. The agent A g 0 has
information about the agents of type A g 0 which correspond to the neighbouring
robots for a given robot, and may communicate with them. This agent has informa-
tion about the tasks assigned to a given robot and these tasks may be sent between
the neighbouring agents of type A g 0 (i.e., between the neighbouring robots).