Environmental Engineering Reference
In-Depth Information
a plan modification (in which case it might send it back requesting that
the submitter determine whether the request could be re-submitted at a
later time). The personal assistant might also determine that other agents
need to be consulted and could set up a “meeting” between the various
relevant agents to try to resolve the question.
Buying/negotiating agents
:
Buying/negotiating agents are asked to acquire
some product or service. The agent interacts with potential suppliers, ne-
gotiates the best overall deal, and sometimes completes the transaction.
One could imagine this type of agent adapted for use in the spacecraft op-
erations domain, acting as an electrical power agent tasked with managing
onboard power resources, in the following scenario.
Suppose that the power agent monitors overall power resources and
has allocated power so as to satisfy all customers' needs (for example,
attitude control subsystem (ACS), propulsion, communication, thermal,
science instruments 1, 2, and 3, etc.). Suddenly the power agent realizes
that a large portion of one of the solar arrays is not producing electrical
power, leading to what will soon be an insucient amount of power to
satisfy all the customers' needs.
The power agent knows what the spacecraft critical functions are and
immediately allocates whatever power those functions need. There re-
mains enough power to continue to perform some science, but not all the
science currently scheduled. At this point, the negotiating agent (possibly
the power agent itself) “talks” with each of the three science instruments
and the science scheduler to decide how best to allocate the remaining
power. The scheduler points out which science (done by which instru-
ments) are the highest priority from a mission standpoint.
The science instruments (which have already been guaranteed the
power they will need to enter and maintain safemode) report what their
special needs are when they transition from safemode to do their science
(for example, warm-up times, re-calibrations, etc.). The scheduler then
produces a draft modified schedule, which the negotiating agent checks
for power validity, i.e., do they have enough power to “buy” the pro-
posed schedule. If they do, the negotiating agent contacts ground con-
trol (through the communications agent) to obtain ground control's bless-
ing to change the schedule, while ground control figures out how to re-
store (if possible) nominal power capabilities. If ground control cannot be
contacted, the negotiating agent will approve executing the draft schedule
until it hears from the ground or some new problem develops (or, less
likely, the original problem disappears on its own).
1.4.2 Robotics
Intelligent robots are self contained mechanical systems under the guidance of
computerized control systems. Intelligent robots have a long history that goes
back to the beginning of computer control. While they share many features
