Research on operation area determination method of automatic navigation agricultural machine in a polygon field block

Abstract. . Smooth turning, minimum time consuming and maximum operation area are required for path planning of automatic navigation agricultural machine (ANAM). This paper proposes a novel operation area determination method for a polygon field plot. Firstly, turning types of ANAM and the corresponding turning width is determined. Then, concavity or convexity of the polygon field plot is judged so that operation area of the field plots can be calculated by using corresponding methods. For a convex polygon field plot, arbitrary point inside of convex polygon is selected as a reference point. And moving direction of each edge depends on the relative position relationship between the reference point and the edge, namely, each edge moves towards the reference point. For a concave polygon field plot, moving direction of each edge is determined based on the relative position relationship among three vertexes of two adjacent edges. It is judged firstly whether the common point of two adjacent edges is concave point or not. When concave point is the case, two adjacent edges move opposite to the moving pattern of the case of convex polygon. Otherwise, two adjacent edges shift in line with that of convex polygon field plot as the triangle is eternally a convex polygon. Finally, the operation area of ANAM is obtained as indented polygon of the field plot. Simulation study proves that the proposed algorithm can achieve the suitable operation area of ANAM in a polygon field plot.