Risk and gain battery management for self-docking mobile robots

Battery management of mobile robots has not been a strong focus of attention and is usually addressed by the simple use of battery thresholds. As a result decision of redirection to a charging station is fixed and takes into account neither a dynamic evaluation of the risk of battery depletion nor an evaluation of the gain, defined as the level of mission accomplishment that could be achieved. To address this issue, we propose a method of assessment of risk of battery depletion which achieves robustness toward unexpected events through the use of probability density functions. This risk assessment allows replacing the usage of battery threshold by a customizable risk-taking parameter, guaranteeing that redirection to the station corresponds to a favorable compromise between risk and level of mission accomplishment. In this paper, we evaluate this approach for self-docking mobile robots, in particular for situations characterized by discrete gain functions, such as mail delivery and garbage collector robots.