Relation between skill acquisition and task specific human speech in collaborative work

To accomplish the objective to make human-collaborative robots, we need to clarify how humans actually interact each other when they do collaborative work. In this study, we transcribed all utterances produced while participants' completing human-human collaborative conveyer task, and computed and categorized all morphemes (minimal unit of language meaning) using 4 categories based on the morpheme's role in the task. The role categories were Robot Action, User Action, Modifier, Object. We analyzed the utterances produced by 4 groups, 3 participants in each group. Results were that frequency of each category per minute decreased over ten trials. However, the variety of words in each category tended to show an inverted U-shaped pattern. Based on these results, we proposed three stages of language skill acquisition in a collaborative work.