Abstract—Indoor navigation technology has enabled the exploitation of mobile robots for transportation of goods/materials in industry facilities/warehouses. Nevertheless, the deployment of a number of mobile robots segregated to individual tasks may limit the advantages of such technology. The achievement of a solution where a mobile robot capability is enhanced by aggregating passive mechanisms (i.e. passive trailers) represents a more cost effective and versatile solution. Therefore, the analysis of safety and performance of such configuration is a step forward toward the full deployment of this kind of systems. With this work, we attempt to contribute to this field by studying of the effects of system uncertainties, disturbances and changing operating conditions on the behavior of such systems. Specifically, we model the dynamics of a mobile robot towing an off-axle trailer with two wheels configurations and then incorporate the movement of the caster wheels in the dynamics model. Such a model would enable the synthesis of robust control schemes to achieve a better tracking capability and consistent performance in real operating scenarios.
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