posed into three functional elements: sensing, plan-
ning, and executing (Nilsson, 1980). The sensing sys-
tem translates the camera image into an internal world
model. The planner takes the internal world model
and a goal and generates a plan (i.e., a series of ac-
tions) that would achieve the goal. The executor takes
the plan and sends the actions to the robot. This ap-
proach is called the sense-plan-act (SPA) paradigm.
But the SPA paradigm has problems. First, plan-
ning in any realworld domain takes a long time, and
the robot would be blocked waiting for planning to
complete. Second, and more importantly, execution
of a plan without involving sensing is dangerous in a
dynamic world.
The second kind of architecture is Reactive plan-
ning in which plans are generated quickly and relied
more directly on sensed information (Fir, ). The most
influential work, however, is the Subsumption archi-
tecture of Rodney Brooks of MIT (Brooks, 1986a). A
Subsumption architecture is built from layers of in-
teracting finite state machines each connecting sen-
sors to actuators directly. These finite state machines
were called behaviors (leading some to call Sub-
sumption ”behavior-based” or ”behavioral” robotics
(Arkin, 1998)).
However, it is very difficult to compose behaviors
to achieve long-range goals and it is almost impossi-
ble to optimize robot behavior.
The last kind of architecture is Layered Robot
Control Architectures. Among the many instances
of layered architectures, we can distinguish between
two fundamental classes: horizontally layered archi-
tectures (such as the ones developed by (Brooks,
1986b), (Kaelbling, 1990), and (Ferguson, 1992))
and vertically layered architectures (such as MECCA
(D. D. Steiner and Lerin, 1993) and (Muller and Pis-
chel, 1994)). Whereas all the layers of an agent have
access both to the perception and action components
in horizontal architectures, only one (and normally:
the lowest) layer has a direct interface to these facili-
ties in the vertical approach.
Currently two kinds of contributions in the multi-
robot systems are considered related to this paper,
namely reactivity and social cooperation.
The difference of the architecture proposed in this pa-
per lies in emphasis on reactivity and social cooper-
ation between multiple robots, while most of other
architectures analysed by Goodwin (Goodwin, 2008)
are concentrating on controlling multiple parts of a
single robot.
The main difference of the proposed architecture
from STEAM (Tambe, 1997) is in the task allocation
mechanism. While STEAM uses the main task coor-
dinator (team leader) that issues orders to team mem-
bers, the proposed architecture focuses on individual
agents being able to apply for tasks, therefore increas-
ing their autonomy.
In ALLIANCE (Simmons, 1994), it is harder to
replace actual robots with a software simulator, be-
cause single point of interface between deliberative
and reactive layers makes it easier to test application.
The main difference from CENTIBOTS is in com-
plexity of each robot CENTIBOT system uses robots
with complex sensors and processing units while
the proposed architecture focuses on use of low-cost
hardware and in order to achieve sufficient environ-
mental data quality, supplements deliberative level
with appropriate algorithms and intelligence.
9 CONCLUSION
The main aim of this paper is how to ensure a dis-
tributed planning in Multi-Robot System composed
of several intelligent autonomous robotic agents able
to take the initiative instead of simply reacting in
response to its environment. Our solution to this
problem is the use of the 5 Capabilities Model (as
it was presented, 5 levels: Environment, Self, Plan-
ner, Competence and Communication). The 5 Ca-
pabilities Model can be easily implemented where
each model is represented with a process collaborat-
ing with the other processes. The 5C Model, based
on the principle of separation of concerns, has the
following interests: (i) The design is general enough
to cope with various kinds of embedded-software ap-
plication (therefore, the 5C Model is uncoupled from
the application); (ii) The robotic agent is represented
through five dimensions where each model is inde-
pendent from the other which permits to change one
without having to change the other.
Our future work is the design of an autonomous
robot integrating cognitive abilities with other capa-
bilities such as locomotion, prehension and manipu-
lation.
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