Developmental psychology presents us with a puzzle: though children are remarkably apt at planning their actions, theysuffer from surprising yet consistent shortcomings. We argue that these patterns of triumph and failure can be broadlycaptured by the framework of task and motion planning, where plans are hybrid entities consisting of both a structured,symbolic skeleton and a continuous, low-level trajectory. As a proof of concept, we model two case studies from the tooluse literature and show how their results can be understood by the interaction of symbolic and continuous plans.

Humans make plans with remarkable flexibility by leveraging symbolic representations. How are these representationslearned? We present a model that starts out with a language of low-level physical constraints and, by observing expertdemonstrations, builds up a library of high-level concepts that afford planning and action understanding. We demonstrateits versatility through experiments inspired by developmental psychology literature.