## 4 Simulations
The graph in Figure 10b shows that the system was able to successfully extract all four boxes. A collision occurred when the tool was inserted to extract the third box, and a second estimation of the gap was required for the task to be successfully completed. It is noteworthy that each extraction showed a similar behavior, and a comparable completion time (with the exception of the collision case). Moreover, the robot was moving at only \(10\%\) its maximum speed. Therefore, the expected performance obtained in Section 4 can be easily achieved if the robot arm was moving at full speed. Figure 9: Overall insertion success rate with respect to gap detection repetitions. ## 7 Conclusions and Future Work

In this paper, a novel mobile manipulator equipped with a 3D perception system for autonomous depalletizing tasks was presented. The proposed solution shows that it is possible to unload, in a controlled way, just a few boxes from a pallet, without the need of disassembling an entire pallet layer. Therefore, the system can be very effective to build mixed pallets containing different types of goods, in which only a small number of boxes of the same type are needed. Future work will be devoted to the evaluation of the proposed system in an industrial scenario, which was not possible due to COVID-19-related restrictions. Moreover, the implementation of the depalletizing task will be extended to handle packages of bottles and cans, which will require a more complex manipulation plan. We will also consider the task of building a complete mixed pallet, including the collection of small lots of boxes from multiple single-item pallets and their arrangement on the mixed pallet in a proper order. Conceptualization, J.A., A.B., M.C., G.P., L.S. ; methodology, R.M., M.B., A.B., D.L.R., G.P., F.Z. ; software, R.M., D.C., J.R.; validation, G.S., F.Z., D.C., J.R.; writing--original draft preparation, R.M., J.A., F.Z., A.B., R.D.L., G.I., S.F. ; writing--review and editing, M.C., L.S. ; supervision, J.A., R.D.L., C.F., G.I., M.C., D.L.R., C.M., L.S. ; funding acquisition, J.A., C.F. All authors have read and agreed to the published version of the manuscript. This work was supported by the COORSA project (European Regional Development Fund POR-FESR 2014-2020, Research and Innovation of the Region Emilia-Romagna, CUP E81F18000300009). The authors declare no conflict of interest. ## References

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