Object Action Complex

Object-Action Complexes (OACs) are proposed as a universal representation enabling efficient planning and execution of purposeful action at all levels of a cognitive architecture. OACs combine the representational and computational efficiency for purposes of search (the frame problem) of STRIPS rules (Fikes 1971) and the object- and situation-oriented concept of affordance (Gibson 1950, Sahin et al. 2007) with the logical clarity of the event calculus (Kowalski et al. 1986, Steedman 2002). Affordance is the relation between a situation, usually including an object of a defined type, and the actions that it allows. While affordances have mostly been analyzed in their purely perceptual aspect, the OAC concept defines them more generally as state-transition functions suited to prediction. Such functions can be used for efficient forward-chaining planning, learning, and execution of actions represented simultaneously at multiple levels in an embodied agent architecture.

The PACO+ project link title, an Integrated Project funded by the European Commission through its Cognition Unit under the Information Society Technologies of the sixth Framework Programme (FP6), and launched on 1st of February 2006, brings together an interdisciplinary research team to design and build cognitive robots capable of developing perceptual, behavioural and cognitive categories that can be used, communicated and shared with other humans and artificial agents. In the project they hypothesize that such understanding can only be attained by embodied agents and requires the simultaneous consideration of perception and action resting on three foundational assumptions

   * Objects and Actions are inseparably intertwined in cognitive processing; that is “Object-Action Complexes” (OACs) are the building blocks of cognition.
   * Cognition is based on reflective learning, contextualizing and then reinterpreting OACs to learn more abstract OACs, through a grounded sensing and action cycle.
   * The core measure of effectiveness for all learned cognitive structures is: Do they increase situation reproducibility and/or reduce situational uncertainty in ways that allow the agent to achieve its goals?