Figure 4
The 3 D plot showing four trajectories in an x, y, and z space. The horizontal axes, on the right, represent x (meters) and ranges from 0 to 10, and on the left represent y (meters) and ranges from negative 2 to 4. The vertical axis represents z (meters) and ranges from negative 2 to 6. A legend identifies the plotted curves: a red curve labeled “trajectory in this paper”, a green curve labeled “trajectory in open square bracket 18 close square bracket ”, a blue curve labeled “trajectory in open square bracket 29 close square bracket ”, and a purple dashed curve labeled “reference”. All trajectories begin from an annotated “Initial position” located at a high positive z-value and near the origin in x and y. The curves descend in spiraling or looping shapes as they move outward along both horizontal axes. Near the lower z-region (approximately negative 2 meter), several “Final position” labels appear in red, green, blue, and purple, marking where each method’s trajectory converges. Note: All numerical data values are approximated.Underwater robot trajectory