Hsiao, K. "Embodied Object Schemas for Grounding Language Use"

Abstract

This thesis presents the Object Schema Model (OSM) for grounded language interaction. Dynamic representations of objects are used as the central point of coordination between actions, sensations, planning, and language use. Objects are modeled as object schemas" sets of multimodal, object-directed behavior processes"each of which can make predictions, take actions, and collate sensations, in the modalities of touch, vision, and motor control. This process-centered view allows the system to respond continuously to real-world activity, while still viewing objects as stabilized representations for planning and speech interaction. The model can be described from four perspectives, each organizing and manipulating behavior processes in a different way. The first perspective views behavior processes like thread objects, running concurrently to carry out their respective functions. The second perspective organizes the behavior processes into object schemas. The third perspective organizes the behavior processes into plan hierarchies to coordinate actions. The fourth perspective creates new behavior processes in response to language input. Results from interactions with objects are used to update the object schemas, which then influence subsequent plans and actions. A continuous planning algorithm examines the current object schemas to choose between candidate processes according to a set of primary motivations, such as responding to collisions, exploring objects, and interacting with the human. An instance of the model has been implemented using a physical robotic manipulator. The implemented system is able to interpret basic speech acts that relate to perception of, and actions upon, objects in the robot's physical environment.