An infant inspired model of reaching for a humanoid robot

Infants demonstrate remarkable talents in learning to control their sensor and motor systems. In particular the ability to reach to objects using visual feedback requires overcoming several issues related to coordination, spatial transformations, redundancy, and complex learning spaces, that are also challenges for robotics. The development sequence from tabula rasa to early successful reaching includes learning of saccade control, gaze control, torso control, and visually elicited reaching and grasping in 3D space. This sequence is an essential progression in the acquisition of manipulation behaviour. In this paper we outline the biological and psychological processes behind this sequence, and describe how they can be interpreted to enable cumulative learning of reaching behaviours in robots. Our implementation on an iCub robot produces reaching and manipulation behaviours from scratch in around 2.5 hours. We show snapshots of the learning spaces during this process, and comment on how timing of stage transition impacts on learning.