The application discloses an unmanned ship autonomous return method, device and
system based on historical trajectory. t t The method comprises the following steps: acquiring a position point (x t , y t ) of the unmanned ship in real time, removing position points which are approximately overlapped in space at adjacent time points, obtaining an original position
point set, searching the original position
point set in
time sequence, taking position points meeting constraint conditions as connected nodes, and
numbering the connected nodes; constructing a topological
structure diagram of historical motion trajectory based on the connected nodes, and sequentially calculating distances between the connected nodes; constructing a two-dimensional
adjacency matrix according to the topological
structure diagram, and searching and determining a shortest path of the historical motion trajectory from a starting point to an ending point and target nodes passed through by using a graph search method; and the unmanned ship autonomously returns according to an autonomous return path planned according to the shortest path and the target nodes. The method is simple, accurate, low in
energy consumption, suitable for various complex
water area conditions, and capable of improving stability of the unmanned ship when performing a task.