Creating a network from MRN for use in MapInfo RouteFinder

Introduction

RouteFinder is a 3rd party extension to MapInfo which gives users the ability to create and manage network data sets in MapInfo and perform detailed analysis on the data.

RouteFinder supports both OS NGD Transport Network and OS Multi-Modal Routing Network (MRN). In this article we are going to look at how to create a network using the MRN data set.

Converting the data into a suitable format

The first step is to create an order for the data in the OS Data Hub for your area of interest. The data is available as both Protocol buffer Binary Format (PBF) and Geopackage formats, for use with RouteFinder you will need to select Geopackage. The data is found in the Data Hub under Data > Downloads > Premium Data.

Please note that if you want to create TAB or Shape files as your output then there is a file size restriction of 2GB. When dealing with larger dataset you can use create an extended MapInfo Table (TabX) or MapInfo MIF which can be imported into other systems.

To give examples of different areas I have downloaded New Forest District Council (a rural area with a number of small towns) and Birmingham (an urban area).

To convert the Geopackage file into a suitable format you will need to use the OS MRN RouteWare converter (further details can be found on the RouteWare website). Each link in the MRN data has an attribute indicating the type of access (e.g. car, foot, rail etc) the converter allows you to select which of these you want use in your network. For this example we have left the defaults and ensured that Avoid pattern and os_roadwidthminimum are selected as this will be of use in our walking routes.

You can also select which speed information to include, as Indicative speed limits (in mph and kph) and average road speeds (in kph) are available as attribution in MRN.

Viewing the data in MapInfo

Before we start creating the network dataset open the TAB file in MapInfo to explore the data. The coordinate reference system of the MRN product is the World Geodetic System (WGS84: EPSG: 4326), therefore if you wish to add a base map it is recommended that you use OS Maps API ESPG: 4326 in the styling of your choice.

You will notice that MRN differs from OS NGD Transport Networks as it contains road links, path links, connecting links, ferry links, and railway links as one layer, with attribution to indicate the type of transport that can access it..

One feature you will note is modal change points which are used to show where you can change mode of transport, for example connecting to a site such as a car park, bus or train station. These are represented in the data by a series of nodes (Modal Change Point) and straight lines.

Creating a Network

The next step is to create a network dataset for use in RouteFinder. To do this you will first need to add RouteFinder to MapInfo, which is usually accessed through the Tools menu. Then use the Create Network button on the ribbon and select the TAB file you created previously and have added to MapInfo.

In the Select Network Attributes you will need to set the Avoid Column to the avoidpattern attribute.

This is important as you will use this to avoid using certain types of transport link in your analysis

Performing Walk time analysis

Setting Avoids – the first step in the analysis is to set up avoids, these are used to create a set of links that should be avoided when calculating a route, for example a road that it is not safe to walk along. There are 4 initial avoids already set by default with the following values:-

Avoid value 1 excludes motorways

Avoid value 2 excludes paths

Avoid value 4 excludes railways

Avoid value 8 excludes ferries

Therefore to create a route that avoids using motorways we would use avoid pattern 1. Additional categories can be added using bit notation, so the next value would be 16, 32 and so on. For example you can add an additional avoid for road links that might not have a path alongside or considered too dangerous to walk along by assigning an avoid pattern of 16 to the links.

As these are set by default, we need to create a profile for walking routes by selecting the Preference drop down and Route. In the open dialogue click Add and then enter Foot as the Vehicle Name. As we want a walking route we need to avoid walking on motorways, so we check Motorways under Avoid and set the Maximum Speed to 6Km for walking.

I have also created an avoid called Narrow paths which we will discuss later.

Creating a route

Once completed we are ready to calculate walking routes using the Route tool and clicking on the start and end point of your chosen route.

To enhance the analysis you may want to use some of the attribution in MRN or add other data sets. For example roads that are narrow may be considered to be unsafe to walk along. By using the minimum road width attribute to select all links with a value of less than 2 metres and setting these as avoid value 16 and changing category 5 to Narrow Roads. Selecting this avoid then excludes these from the route.

Adding other data

It would be useful to enhance our results with other datasets for example the Street Light Feature Type from NGD Transport Features. This feature type describes the location of street lights as a point feature. In this example, I want to identify which parts of my route are lit. The NGD Street Light feature type contains a reference to the road or path link it applies to. However, as the reference isn’t present in our translated feature set instead we will load the Street Lights as a Geopackage into MapInfo and use Select By Location to select all points that are within 5 metres of our route. This now highlights which sections of our route are unlit and may be considered unsafe to walk along.

For more details on Routefinder visit Higher Mapping Solutions – Providing Advanced GIS Solutions

With acknowledgement to Martin Hodder of Higher Mapping Solutions and Uffe Kousgaard of Routeware.