Fleet Telematics Custom Locations Developer's Guide

Searching along a Route's Isoline

This section clarifies the 3 different functions HLS Router Isoline Routing, Search along Route Isoline and WSE Pickup along Route.

HLS Router offers Isoline and Reverse Isoline functions. As shown in the figure, the result is a polygon covering all road links that can be reached from the given location (left polygon) within a certain amount of driving time (or distance). Similarly, all road links from where the given location (middle polygon) can be reached within a certain amount of driving time (or distance).
Figure 1. HLS Router's Isoline Functions
The rightmost polygon in the figure shows that the main purpose is map display, because it is not guaranteed that each link covered by the spanning polygon is actually within reach. The red link outlines a motorway with exits on both ends but not within the isoline polygon. A car driving on this motoryway cannot reach the location within the time/distance limit. offers accuracy on link level.
A Isoline along a Route is a buffer along a route path. This buffer covers either of following:
  • The set of links that are either on the route path or can be reached by a detour of less than N seconds from the route.
  • The set of links that are either on the route path or can be reached by a detour of less than N meters from the route.
  • The set of custom geometries that are either on (attached to a link of) the route path or (attached to a link that) can be reached by a detour of less than N seconds from the route.
  • The set of custom geometries that are either on (attached to a link of) the route path or (attached to a link that) can be reached by a detour of less than N meters from the route.
The detour is measured from the exit on the route to the center of the link. The detour to return onto the route is disregarded. The idea is, that this function is a first step, followed by a second step to select links/POIs and a thrid step to compute the final route.
Isolines along a Route are accurate on link level, a the following figure shows (left).
Figure 2. 's Isoline along Route
The right side of the figure shows, how Isolines along a Route can be used to obtain a link-level-accurate version of HLS Router's Isoline function (but not yet for its Reverse Isoline function): Define a very short route (almost a point) around the location.
WSE Pickup along Route identifies which optional way points along a route are worth being met. The goal is optimization of the overall route driving cost, including the cost per kilometer (aka driver cost) and the cost per hour (aka vehicle cost) for the route including all detours to pickup and drop off goods or persons. The figure shows an example: Is it worthwhile to pickup one of the persons (or both) on my route from (0) to (1)? They want to be picked up where the face is shown and dropped off at where the reward $ is shown.
Figure 3. WSE's Pickup along Route Function