SAFEPASS: Safe Encounter Resolution using Passive Sensing

Range estimation for marine vessels is of vital importance to unmanned surface vehicles for COLREGS-compliant navigation and collision prevention. For USVs operating in EMCON, it may be desired to estimate distance using a monocular camera, given the limited effective range of stereo camera systems. SAFEPASS provides passive ranging, tracking, and obstacle/collision avoidance to an autonomous USV with the addition of a low-cost, COTS pan, tilt, zoom camera system. Taking inspiration from history’s navigators, SAFEPASS performs passive ranging with a combination of Target Motion Analysis, Rate of Growth, and Stadimeter techniques. Closed-loop perception enables the system to produce the optimal maneuvers to reduce uncertainty of contact tracks while still maintaining mission objectives and maintaining safe separation. SAFEPASS leverages a long history of computer vision, maritime autonomy, and mission optimization tools developed at SSCI and the Phase II work plan will demonstrate the concept in on-water tests.