Mobile robot battery life estimation: battery energy use of an unmanned ground vehicle

Engineers find it of importance to have a quantitative understanding of the charge-depletion characteristics of the battery-bank that powers a mobile unmanned ground vehicle (UGV) so as to have mission-duration, cost-of-transport, range, and other useful estimates. Data analysis to determine the energy use of a ‘large’ wheeled robot – the Clearpath™ Warthog – with Gross Vehicle Weight (GVW) 590 Kg. -- are here discussed. The analysis is based on gravel-surface, straight-path level trials. The results of this analysis inform how far the UGV can travel over the specified surface. We give basic methods for obtaining expected energy usage: tables with estimates for cost of transport and for mission range. Included in the analysis is a nonparametric method for identifying and dealing with the small number of ‘outlier,’ readings that often occur in field trials.