In Chapter 1 we exposed the idea that intelligence might be perceived from the
adaptiveness of the behaviour in an individual. For example, if an animal avoids successfully
its predators, we will say that he behaved intelligently (at least, more intelligently than the eaten
ones...). If a robot is capable of successfully navigating through crowded corridors, we will say
that he also behaved intelligently.
In this chapter we expose first a brief review of action selection mechanisms and what
are they. Then, we present the Behavioural Columns Architecture15 (BeCA) (Gonzalez, 2000),
a behaviours production system (BPS) for AAAs inspired in ethology and implemented in a
double blackboard architecture. We do this by first defining and describing Behaviours
Production Systems and giving a brief description of the Blackboard Node Architecture. Next
we introduce the elements of BeCA, in order to model in an evolutionary bottom-up fashion
reflex, reactive, and motivated behaviours. Then we refine our BPS by implementing two
learning schemes: associative learning, and a simple reinforcement learning of the motivation
degree. Finally we describe the properties of BeCA.
BeCA was used to provide the control of the animats of our Behaviours Virtual
Laboratory, presented in Chapter 5.
3.1. Action Selection Mechanisms
“Look to nature, and let simulated nature take its course”
—Andy Clark
An action selection mechanism (ASM) computes which action should be executed by
a BBS in dependence of the internal state and the external perceptions of the agent controlled
by the BBS.
The building of ASMs has two benefits, which feedback each other: the better
understanding of adaptive behaviour (how animals are able to adapt to their environment), and
the development of adaptive artificial creatures.
Reviews of ASMs can be found in (Gonzalez, 2000) and (Tyrrell, 1993).
Here we present a brief review of works related to ASMs, taken from Gonzalez et. al.
(2000):
• Tinbergen's mechanism (Tinbergen, 1950; 1951), a hierarchic network of nodes or
centres, which approaches the complete action selection problem with a noticeable
emphasis in the reproductive stage.
• Lorenz's psycho-hydraulic mechanism (Lorenz, 1950; 1981), a model that tries to explain
some ethological phenomena, without completely approaching the action selection
problem.
• Baerends' model (Baerends, 1976), a hierarchic network of nodes, a model inspired by
ethologist studies made in particular species of insects and birds.
15BeCA has been developed by Pedro Pablo Gonzalez, Jose Negrete, Ariel Barreiro, and the author.
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