A Gravity Gradient Differential Ratio Method for Underwater Object Detection

The smooth operation of autonomous underwater vehicles (AUVs) relies heavily on the accurate detection of surrounding objects. Toward this end, this letter presents a novel method for underwater object detection based on the gravity gradient differential and the gravity gradient differential ratio caused by the relative motion between the AUV and the object. Unlike the existing techniques, the proposed method works in a passive manner and achieves AUV invisibility without energy emission. In addition, for the proposed method, no gravity map or gravity gradient map is required, which improves its practicality. Experimental results demonstrate that the proposed method performs better than the existing methods.