Environmental Engineering Reference
In-Depth Information
communicate the plan to the subordinates. The subordinate agent receives
the plan as a series of goals. These goals are interpreted from the agent's
perspective and a plan is generated and executed. The subordinate agent
then senses its local environment to determine how to continue the pursuit of
its goals.
Hierarchical cooperation is not peer to peer. While a subordinate can nego-
tiate with its superior by communicating its goals, resources, and constraints,
it does not make the choice on what will be done. Once the superior has made
these choices, the subordinate must attempt to achieve the goals to the best
of its ability.
Hierarchical cooperation can be found in many business organizations. The
superior agent in Fig.
7.4
could represent a senior management group and the
subordinate agent a department within the company. The senior management
group sets goals and priorities for the department. The department manager,
usually at department status meetings, distributes these goals in the depart-
ment. The department manager also brings back the results of the department
to the senior management group. In this way, the perceptions of the depart-
ment become part of the perceptions of the senior management.
Computerized systems allow the connection between hierarchical layers to
be much tighter than is possible in human cooperation. In these systems, the
two levels are directly connected together with the action of the superior agent
directly converted into plans for the subordinate agent. Figure
7.5
depicts
this scenario. An excellent example of this type of hierarchical cooperation
can be found in many robotic control systems. An upper level agent is a
slow and deliberative planner that determines the overall strategic goals. The
subordinate agent is a high-speed reactive planner. This planner converts the
high level goals into direct robotic actions and responds rapidly to changes in
the environment.
Fig. 7.5.
Tightly coupled hierarchical cooperation
