Fast Path Planning Method for Agricultural Robot Automatic Guidance based on Cubic Spline Interpolation in Strip Farming

In the autonomous navigation of agricultural robots in the field, the number of path nodes determines the smoothness of the robot's movement. However, the process of defining node positions is time-consuming and labor-intensive. In this study, a path planning method based on cubic spline interpolation is proposed to reduce the time of node position definition and configuration. At the same time, the use of this method can also maintain the stability of the steering control of agricultural robots, so that the robot can move smoothly. First, select several path nodes in the strip field as control points using cubic spline interpolation. Combines the complete path of a polyline segment by interpolating the path of the start point, control point, and landmark point between the straight path and the turn path. A small number of path node locations are defined by the global navigation satellite system with real-time kinematics (GNSS-RTK) system, and a robot dynamics system is used to actually simulate the feasibility of the proposed model in a strip field environment. The simulation results verify the effectiveness of the proposed algorithm. This method can reduce the number of path node position definitions and maintain the accuracy of the robot's route travel.