“…The RNs are pre-positioned on static coordinates, and the BN is fixed on the robot. When the UWB localization system works, BN is used to collect the ranges d U i , i ∈ [1,4] from i th RN to BN. Then, the ranges d U i , i ∈ [1,4] are input to the multi-interval EFIR Rauch-Tung-Striebel (ERTS) smoother, which used as the data fusion filter in this work.…”