Olivier Georgeon's research blog—also known as the story of little Ernest, the developmental agent.

Keywords: situated cognition, constructivist learning, intrinsic motivation, bottom-up self-programming, individuation, theory of enaction, developmental learning, artificial sense-making, biologically inspired cognitive architectures, agnostic agents (without ontological assumptions about the environment).

Friday, April 1, 2011

Ernest 9.3

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The colliculus activation algorithm has been improved. This gives Ernest 9.3 a smoother behavior than Ernest 9.2 (e.g., see the elegant curve taken on the way back to the hive on steps 356-388).

In addition, Ernest's thorax now takes the color of the most motivating landmark in the visual field—the landmark that raises the most activation in the colliculus. This landmark is the object of Ernest's current attention and drives Ernest's homing tendency.

At the beginning, Ernest is seeking to gather pollen but he does not know how to distinguish flowers from other landmarks. The highest activation is only given by the largest landmark in the visual field (i.e., the closest landmark). This causes Ernest to visit all landmarks randomly. When a landmark is visited, this landmark's activation is lowered for some time, meaning that Ernest temporarily looses interest in this landmark. This causes Ernest to move on to another landmark.

On step 38, Ernest finds a landmark from which he can gather the pollen (the blue flower). This switches his motivation to make him seek for the hive. In the hive-seeking motivational mode, landmarks raise an additional activation that is proportional to their proximity to the hive (or to Ernest's place of birth) as much as Ernest remembers from his way out. This activation mechanism causes Ernest to go back to the yellow square by traveling from known landmarks to known landmarks. After reaching the yellow square (step 83) he finds no more motivating landmarks and starts a random exploration again until he finds the hive for the first time on step 94.

When on the hive, Ernest drops the pollen and switches back to the pollen-seeking motivational mode. Now, the highest activation is generated by landmarks that Ernest remembers as being the closest to the pollen. This leads Ernest back to the northeast flower field. On the second way back, Ernest is now able to recognize the hive, which causes him to turn directly towards the hive on step 159 (by-passing the yellow square).

When the northeast flower field is empty, Ernest fumbles again until he sees new landmarks to explore (green landmarks in the southeast field on step 311). From then on, he starts exploiting the southeast field the same way he exploited the northeast field.

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