Development of imaging sonar based autonomous trajectory backtracking using AUVs

We proposed an autonomous trajectory backtracking method using forward-looking imaging sonar. Additionally, we also dealt with a Fourier-based sonar image processing for the autonomous trajectory backtracking. We suggested an algorithm to estimate translational shifts and rotation angle between two sonar images. By feeding back the estimated data, AUV can compensate the drift error of dead-reckoning. To verify these algorithms, we used the field data obtained by the forward-looking imaging sonar of hovering-type AUV `Cyclops'. We verified accuracy and tolerance of the proposed algorithm by performing experiments.