Incremental development of multiple tool models for robotic reaching through autonomous exploration

Autonomy and flexibility are two major requirements for modern robots. In particular, humanoid robots should learn new skills incrementally through autonomous exploration, and adapt to di erent contexts. In this paper we consider the problem of learning forward models for task space control under dynamically varying kinematic contexts: the robot learns incrementally and autonomously its forward kinematics under di erent contexts, represented by the inclusion of di erent tools, and exploits the learned model to realize reaching with those tools. We model the forward kinematics as a multi-valued function, in which di erent outputs for the same input query are related to di erent tools (i.e. contexts). The model is estimated using IMLE, a recent online learning algorithm for multi-valued regression, and used for control. No information is given about the tool changes, nor any assumption is made about the tool kinematics. Results are provided both in simulation and with a full-body humanoid. In the latter case we show how the robot successfully performs reaching using a flexible tool, a clear example of complex kinematics.