title: Humanoid infers Archimedes' principle: understanding physical relations and object affordances through cumulative learning experiences.
abstract: Emerging studies indicate that several species such as corvids, apes and children solve 'The Crow and the Pitcher' task (from Aesop's Fables) in diverse conditions. Hidden beneath this fascinating paradigm is a fundamental question: by cumulatively interacting with different objects, how can an agent abstract the underlying cause-effect relations to predict and creatively exploit potential affordances of novel objects in the context of sought goals? Re-enacting this Aesop's Fable task on a humanoid within an open-ended 'learning-prediction-abstraction' loop, we address this problem and (i) present a brain-guided neural framework that emulates rapid one-shot encoding of ongoing experiences into a long-term memory and (ii) propose four task-agnostic learning rules (elimination, growth, uncertainty and status quo) that correlate predictions from remembered past experiences with the unfolding present situation to gradually abstract the underlying causal relations. Driven by the proposed architecture, the ensuing robot behaviours illustrated causal learning and anticipation similar to natural agents. Results further demonstrate that by cumulatively interacting with few objects, the predictions of the robot in case of novel objects converge close to the physical law, i.e. the Archimedes principle: this being independent of both the objects explored during learning and the order of their cumulative exploration.
authors.affiliation: Robotics, Brain and Cognitive Science Department, Istituto Italiano di Tecnologia, Via Morego 30, Genova, Italy.
authors.forename: Ajaz Ahmad
authors.identifier: 0000-0002-6992-8224
authors.initials: AA
authors.lastname: Bhat
authors.affiliation: Robotics, Brain and Cognitive Science Department, Istituto Italiano di Tecnologia, Via Morego 30, Genova, Italy vishwanathan.mohan@iit.it.
authors.forename: Vishwanathan
authors.identifier: 0000-0001-5537-9503
authors.initials: V
authors.lastname: Mohan
authors.affiliation: Robotics, Brain and Cognitive Science Department, Istituto Italiano di Tecnologia, Via Morego 30, Genova, Italy.
authors.forename: Giulio
authors.identifier: 0000-0003-3324-985X
authors.initials: G
authors.lastname: Sandini
authors.affiliation: Robotics, Brain and Cognitive Science Department, Istituto Italiano di Tecnologia, Via Morego 30, Genova, Italy.
authors.forename: Pietro
authors.identifier: 0000-0002-3837-8004
authors.initials: P
authors.lastname: Morasso
mesh_terms: D000818:Animals; D015186:Hominidae / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D057567:Memory, Long-Term / Q000502:physiology*; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*
keywords: affordances; animal cognition; cause–effect relations; developmental robotics; episodic memory