Study of Morphological Development as a Tool for Learning Robotic Controllers

Abstract

Humans and animals undergo morphological development from infancy to adulthood, which takes place in parallel with cognitive development. In fact, this process has been shown to facilitate learning in humans. However, most of the works on developmental robotics consider fixed morphologies, addressing only the development of the cognitive system of the robots and ignoring the interaction between cognitive development and morphological development. Moreover, the few cases found in the literature where cognitive and morphological development are jointly addressed in robotic systems present rather heterogeneous and inconclusive results regarding the causes and the mechanisms that explain the influence of morphological development on learning. This work addresses the problem of identifying those features of morphological development that influence learning, as well as how and why this influence comes about. To this end, a simple and controlled experimental framework based on legged robot morphologies has been designed and an extensive series of experiments have been run in order to try to answer these questions. The conclusions obtained from this experimental work have been validated through the successful implementation on a bipedal robot of a morphological development strategy designed using the insights obtained. This has allowed us to posit an initial set of design principles that should be applied in order to produce successful morphological development processes for particular problems.