Abstract:Aiming to address the core challenges faced by agricultural robots in autonomous navigation and path planning under complex farmland environments—particularly in irregular plots and soft, sticky paddy fields where common issues included low coverage rate, excessive turning redundancy, and poor path continuity, a full-coverage path planning algorithm tailored for convex polygonal farmlands and compatible with dual-helix driven agricultural robots was proposed. The algorithm integrated both the geometric characteristics of the farmland and the kinematic constraints of the robot. The working area was initially divided into a central parallel-working zone and a peripheral contour-following zone, corresponding respectively to strip-based traversal paths and boundary-parallel strip traversal paths. The complete path was further segmented into working and non-working paths, including center-region connection paths, inter-region transitions, contour-parallel region transitions, and entry/exit paths. The methodology for generating each type of path was detailed. An optimal working direction was determined via the “long-side-first” principle for the central region, and the Warnsdorff rule was applied to optimize the sequence of strip traversal. Dubins and Reeds-Shepp path models were introduced to enhance continuity and feasibility during turns. Considering metrics such as path length, computation time, and coverage rate, the algorithm was implemented on a dual-helix driven robot and tested in simulations and field experiments across four typical farmland types: rectangular, trapezoidal, irregular quadrilateral, and irregular polygonal plots. Experimental results demonstrated that the proposed algorithm achieved a coverage rate between 96.69% and 97.80%, with a path overlap rate controlled within 1.77%~2.30%. The generated paths were continuous and boundary-safe, indicating strong execution stability and environmental adaptability. The research result can provide a robust and adaptable path planning solution for agricultural robots operating in complex environments, with promising engineering feasibility and application potential.