AccraMobile3

From OpenStreetMap Wiki
Jump to: navigation, search

Accra Mobile 3 is a project launched in July 2017 to map all the Tro tro lines of Accra, Ghana for the Department of Transport (DoT) of Accra Metropolitan Assembly (AMA) into OpenStreetMap.

The collection and mapping process on field started on 19 July and is planned to finish late September.

This page describes the process the tools used to run this project.

Our team entering a Trotro for surveying its line and stops

Bus stops collection

Bus stops will be collected in the field by 6 OSM contributors.

The accounts used are the following:

OSM User Name
accramobileghana1
accramobileghana2
accramobileghana3
accramobileghana4
accramobileghana5
accramobileghana6
accramobileghana7
accramobileghana8
accramobileghana9
accramobileghana10

All the traces are directly uploaded to OpenStreetMap, and we use a custom script to download and rename them all automatically.

Tro tro lines

All the Tro tro lines are listed on this page.

In order to create an unexisting Tro tro line, you can use the dedicated tool created by Jungle Bus directly in this list (by clicking on "create relation").

For every line, 3 relations need to be created: one for the master, one for the outbound and one for the inbound trip.

The outbound trip (from "home station" to "destination") will be labelled "A". And the inbound trip (from the "destination station" to the "home station") will be labelled "B".

The GPS trace while collected will be added to the "GPS trace" mention as a link.

Our team mapping Trotro lines in OpenStreetMap

Data creation

We consider a bus stop at the exact place where passengers wait for the bus. It is different than the stop position of the vehicle that is not part of our scope.

First step is to load in JOSM all the existing data regarding the stops:

Tro tro stop

A bus stop should be mapped as a simple node with the following tags:

Key Value Mandatory Comment
public_transport platform yes This is a waiting area
highway bus_stop yes This is about bus
name * yes The name of the bus stop
official_status unofficial no For an implicit bus stop with no written mention at all
shelter no no For a bus stop with only a pole
shelter yes no For a bus stop with a shelter

More details are available at https://wiki.openstreetmap.org/wiki/Tag:public_transport%3Dplatform

You also can use our custom preset for Tro tro stop creation.

Tro tro line

A Tro tro line should be described with 3 relations :

  • A master relation that describes general information such as the network and the number of the line.
Key Value Mandatory Comment
type route_master yes This is a meta relation
route_master bus yes This is about bus
name * e.g. “Trotro 003 : 37 Lorry Park ↔ Tse Addo”" yes The name of line mentioning its reference number, its 1st and last stop
bus unofficial yes Always used for a Tro tro line
operator * yes Name of the company that operates the service
ref "* e.g. “003”" yes The number of the line (always 3 digits)
frequency * e.g. “7” yes Approximate frequency of Tro tro traffic during traffic peak time (in min)
charge *GHS e.g. “2.1GHS” yes Fare of the line

This relation contains as members only the 2 child relations (direction A and B). More details are available at https://wiki.openstreetmap.org/wiki/Relation:route_master

Exception: if the fare is not the same inward and backward, please mention it in the comment section.

  • Two child relations, one for each direction, embedding all bus stops and the route itself.
Key Value Mandatory Comment
type route yes This is a transport relation
route bus yes This is about bus
name * e.g. “Trotro 003 : Tse Addo → 37 Lorry Park” yes The name of line mentioning its reference number, its 1st and last stop
bus unofficial yes For a Tro tro line
operator * yes Name of the company that operates the service
ref * e.g. “003” yes The number of the line
from * yes The name of the first bus stop
to * yes The name of the last bus stop
travel_time * e.g. “49” yes The time (in min) to travel from the first to the last stop (computed from the GPX track)
roundtrip yes;no no Whether or not the route start and ends at the same place

More details are available at https://wiki.openstreetmap.org/wiki/Relation:route

OSM community having a mapping party in Accra

Quality Assurance

JOSM validation

While mapping in JOSM, you can use the Jungle Bus validator tool to double check quality.

It has been developed specifically for the project in Accra so it's not a generic tool to use everywhere in the World.

It runs the following tests:

# Warning message What is the problem ?
1 Jungle : The route tag is missing (add the tag route = bus/coach/tram/etc) Every transport relation should detail its route type. For AccraMobile3, it would always be route=bus
2 Jungle : The route_master tag is missing (add the tag route_master = bus/coach/tram/etc) Every transport master relation should detail its route type. For AccraMobile3, it would always be route_master=bus
3 Jungle : The route_master tag is missing (change the route tag to route_master) Every meta relation should have a route_master=bus tag. Please change the route tag to a route_master tag
4 Jungle : The network tag is missing Every meta relation should have a network tag. Please add one
5 Jungle : The operator tag is missing Every meta relation should have an operator tag. Please add one
6 Jungle : The ref tag is missing Every meta relation should have a ref tag. Please add one
7 Jungle : The from or to tag is missing Every meta relation should have a from tag and a to tag. Please add them.
8 Jungle : The frequency tag is missing Every meta relation should have a frequency tag. Please add one
9 Jungle : The charge tag is missing Every meta relation should have a charge tag. Please add one
9+ Jungle : The charge tag must end with GHS Every meta relation should have a charge tag ending with GHS. Please check the value for this tag
10 Jungle : The name tag is missing Every bus stop should have a name tag. Please add one
11 Jungle : Is it a bus_stop or a tram_stop ? The tag public_transport=platform is not rendered, please add the legacy tag highway=bus_stop
11+ Jungle : Is it a bus_stop ? The tag public_transport=platform is not rendered, please add the legacy tag highway=bus_stop
12 Jungle : Is it a passenger waiting point (platform) or a stop_position ? The tag highway=bus_stop is ambiguous. If it’s the position where the bus stops, replace it by public_transport=stop_position. If it’s the position where the passengers are waiting, add public_transport=platform
13 Jungle : Add this route relation to a route_master relation All the line variations (route relations) should be part of a line (route_master relation)
14 Jungle : Add the stop to a route relation All the stops should be in at least a line variation (route relation)
15 Jungle : The travel_time tag is missing Every route relation should have a travel_time tag, in minutes. You can use the GPX track to compute one

Online tools

Brand new control tools have been developed (july 2017) by the french OSM community for checking:

  1. transport relations:
    • Weird members of a route_master: list and map
    • Orphan route relation: list and map
    • Relation without any indication of the schema (V1 or V2): list and map
  2. Line traces:
    • discontinuous line: list and map
    • bus stop weirdly far from its route: list and map

Result

All the data mapped is available directly in OpenStreetMap via our overpass API query

See the mapping progress here!

Accra-mapping-16-10-17.gif