Fig 1.
Network model and time slot allocation.
Fig 2.
Time of flight ranging model.
Table 1.
UWB data grouping.
Fig 3.
Snake optimizer algorithm optimization process.
Fig 4.
The process of updating LSTM hyperparameters with the snake optimizer algorithm.
Table 2.
SO-LSTM algorithm parameters.
Fig 5.
Process of UWB location prediction based on LSTM.
Fig 6.
Crane experimental platform.
Fig 7.
Experimental trajectory of crane hook movement in experiment 1.
Fig 8.
Visualization of ranging error in experiment 1.
Fig 9.
SO-LSTM loss value curve.
Fig 10.
Localization trajectory for experiment 1.
Table 3.
Statistical analysis of positioning errors for three localization methods in experiment 1.
Fig 11.
Experiment 1: X-axis positioning estimation error.
Fig 12.
Experiment 1: Y-axis positioning estimation error.
Fig 13.
Experiment 1: Z-axis positioning estimation error.
Table 4.
RMSE for all three axes in experiment 1 with three positioning methods.
Fig 14.
Experimental trajectory of crane hook movement in experiment 2.
Fig 15.
Localization trajectory for experiment 2.
Table 5.
Statistical analysis of positioning errors for three localization methods in experiment 2.
Fig 16.
Experiment 2: X-axis positioning estimation error.
Fig 17.
Experiment 2: Y-axis positioning estimation error.
Fig 18.
Experiment 2: Z-axis positioning estimation error.
Table 6.
RMSE for all three axes in experiment 2 with three positioning methods.
Fig 19.
Analysis of position estimation trajectory errors (a) experiment 1 error histogram (b) experiment 2 error histogram.
Table 7.
Percentage improvement in SO-LSTM positioning accuracy.