A Case studies of the GRAMS reference model - Modeling and Simulation of Complex Systems - page 188

bounded perception (e.g., only neighboring cells within a limited
distance) is not necessary. A single perceive-action takes 0.5 seconds,
or equivalently 5 time steps within the defined simulation time.
A Receive -sensor is used to receive incoming communication mes-
sages. The only incoming communication are the commands which
the warehouse manager may send to a worker-agent. An action of
this sensor includes the reception of the message itself as well as
storing the received message in the internal knowledge base, and is
therefore assumed to take 3 seconds (30 steps within the simulation
time).
Besides these sensor actions, each worker-agent is capable of the
following four effector actions:
A Move -effector allows a worker-agent to move to a neighboring cell
(diagonal moves are allowed). Each action of this effector represents
exactly one movement and takes 1 second (10 time steps).
Picking up articles (either from a platform or storage area) is
modeled by a Pick-Up -effector and takes 5 seconds (50 time steps).
Additional conditions, like maximum transportation capabilities
of worker-agents, may be defined and enforced via appropriate
constraints, but are omitted within this case study.
In the same way as picking up articles, putting down articles is
modeled by a Put-Down -effector and takes also 5 seconds.
While the previous three effectors directly alter the environment (or
at least, try to do so), the fourth effector is of a different kind. The
Plan -effector is an endogenous effector representing the internal
planning process of a worker-agent. As planning is assumed to be
an ongoing process, a single plan-action takes only 1 time step.
The sensors and effectors determine the general capabilities of a
worker-agent; the actual behavior is defined by the interplay of the
sensors and effectors. Figure A.3 illustrates the interplay in the form