Download DAC Distributed Adaptive Control: Tutorial on Foraging

DAC Tutorial on Foraging
the UR. In this way, the adaptive layer fulfills its twofold task of learning the sensory
motor associations and forming internal representations, i.e. the prototypes e for the
planning system of the contextual layer.
Contextual Layer
The contextual layer provides mechanisms for memorising and recalling behavioural
sequences. It comprises two memory structures: a short-term memory (STM), and a
long-term memory (LTM) for the permanent storage of information (see Fig. 2 below).
These allow the system to acquire, retain and express sequences of the sensorimotor
contingencies the adaptive layer generates. The acquisition of information into
memory is done in two steps:
1. Sensorimotor events generated by the adaptive layer are stored in the STM, forming a behavioural sequence.
2.
When a goal state is reached the sequence of sensorimotor events stored
in the STM are copied into the LTM and the STM is initialised.
The information stored in the LTM is then recalled to reach goal states, as follows:
1.
Whenever a new sensory event is generated it is compared with all the
ones stored in the LTM.
2.
The segments of the LTM that are similar enough (similarity defined by
a matching criteria) to the generated one are retrieved.
3.
Retrieved segments from memory contribute to compute the selected
action.
4.
The selection of segments from the LTM is biased by previous experience
to achieve sequential chaining
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