Design of multiple vehicle delivery tours--II other metrics

The methods described in Part I for a ring-radial metric are generalized to a network having a fine nearly rectangular grid of local roads, but possibly with a few fast roads superimposed. To select delivery zones, one should first draw the equi-travel-time contours from the source and then choose nearly rectangular zones with suitable width and orientation relative to the network grid and the local contour lines. Some illustrations are given for an idealized square grid of roads. In this case the rectangular delivery zones should be oriented at 45° to the grid, perpendicular to the contour lines.