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Man and his web atlas
An open collaborative project has citizen cartographers from Miami to Mumbai chipping in with their GPS loggers, making travel easy and precise.
Dharminder Photographer, Lovely Kirana Store and Gill Sarpanch are online. And although these names may sound insignificant to you, these local landmarks in Punjab's Gill village have managed to find a place on a digital map of the world. Mapping places like Gill on the internet are citizens who travel from nook to nukkad with hand-held GPS devices, tracing every route they take.
Their data is then collated to create a 'work-inprogress' map of the planet for an open-source project called the OpenStreetMap (OSM).
When Ludhiana-based professor HS Rai goes for a walk or a drive around town, his GPS logger is always tracking his movements. Once he's back home, he uploads the information from his survey onto his computer;tags them with the names of roads, markets, hospitals and schools, and posts it on the OSM server (www. openstreetmap. org).
"You can keep adding details to the map, improving it each and every time, " says Rai, who is a professor of Guru Nanak Dev Engineering College.
"Given that map data for India is extremely limited in coverage and grossly inaccurate, only a community approach such as OSM can bridge the gap to completeness, " avers Arun Ganesh who started digital mapping in 2008 when India was just a blank space on OpenStreetMap.
The 22-year-old who had newly moved to Chennai from Abu Dhabi to study found it difficult to commute due to lack of good road maps.
"The ones that were sold on streets were of poor quality, outdated and had lots of mistakes, " he says.
So Ganesh would make notes of the names of streets and important landmarks he saw on paper napkins that he picked up from restaurants;go home, browse to that part of the city using satellite imagery and match the roads. "It's like using MS Paint, you just draw lines over roads you see, mark points for landmarks and then give it properties like the type of road, name, etc. "
The open-source project's collaborative nature - which leverages the hard work of individuals by letting them edit maps of their own localities - makes it accurate and relevant.
Ganesh points out that unlike commercial maps, OSM lets you add coordinates of 'points-ofinterest', which could even include postboxes, ATMs and public toilets.
In countries like Germany - where the OSM community is vibrant and active - the level of detailing in the map includes the positions of trees and speed-breakers on a road.
Different users tag different 'points-of-interest'. Like Mumbai-based Abhishek Nagrale who tags road signs. "One-way streets and parking spaces are useful signs to embed on a map, " he says.
To make the marking the various points easy, the 22-year-old records his voice. For example, while walking along Marine Drive, he would record, 'NCPA apartments to the left' and so on. This acts like a reference point that helps him map faster and more accurately. Some cartographers even take photos that can be later embedded into the map.
And then there's Chennai-based Kenneth Gonsalves who specialises in mapping golf courses.
Equipped with a locally-manufactured GPS device fixed onto his backpack and a Nokia E71 phone for making annotations, the software consultant mapped the Coimbatore Golf Course's fairways, greens, bunkers, hazards and trees. He edits the traces and annotations offline on a desktop application before finally uploading it to the OSM site.
In the beginning, the OpenStreetMap project depended solely on systematic ground surveys conducted by volunteers using GPS devices. But with the availability of satellite imagery, contributing to the project has become easier. "We are allowed to trace from Yahoo and Bing satellite imagery, but no mapping service has hi-res coverage of the whole planet and usually only the big cities are covered, " the 58-year old says while explaining the need for OSM which is like a Wikipedia for maps.
OpenStreetMap comes handy especially during times of crisis. Like in the case of Haiti, which suffered an earthquake in 2010, and didn't have up-todate cartographical data.
Volunteers around the world used historic maps, satellite imagery, and local knowledge to create an open base map for Port-au-Prince and other affected areas of the country, thus aiding relief agencies that were there to provide humanitarian help and relief.
Other instances where groups of people have collaborated to quickly map a place are communitylevel mapping projects or what some turn into a social event, called 'Mapathons'.
Organising Mapathons in and around Ludhiana are enthusiasts like Rai who with his team of engineering students have plotted cities and villages in the region including Jalalabad, Barnala, Fazilka and Uggi. One of his students, Parveen Arora, explains how they work: "We handout GPS devices to people who come for the event and train them how to use the instrument. Each person is sent to a different area to collect details and once they are done, the information is marked on the map with the help of map-editing software called JOSM (Java OpenStreetMap Editor).
"The idea is to try and include as many local people as possible because they are in a better position to identify points-of-interest. We also encourage them to keep updating the map on a regular basis, even after the event. "
BUT WHY WOULD YOU UPDATE A MAP?
Ask the 4, 20, 844 contributors of OSM this question, and you might get some answers.
"The map can be used for urban planning, educational and research, as well as for environmental uses such as marking protected wetlands, coastlines, and mangroves, " says Mumbai-based MIT doctoral candidate Shekhar Krishnan who spends time making notes of buildings, temples and other structures as he cycles around Dadar, Matunga and Parel.
"We need an open base map of Greater Mumbai in the public domain, " he says.
And because OpenStreetMap is open data, licensed under the Creative Commons Attribution-ShareAlike 2. 0 licence - unlike other commercial maps - it lets users freely copy, distribute, transmit and adapt the maps and data, as long as it is credited to OpenStreetMap and its contributors. "These maps are important because they can be customised and used for studies, " Krishnan says.
Rai has undertaken another mapping project to plot the "black spots" of Punjab in association with the traffic police and the Punjab Roads & Bridges Development Board. "Our students have surveyed places and identified 400 places on the state's highways, which are very accident prone. We have called these points black spots and are going to release a map pinpointing these areas, " he says.
Also using OSM to create customised maps is neogeographer Arun Ganesh. "More than navigation, these maps are required to study the history and geography of dynamic India. "
They can be used to track developments and do complex analysis, he explains. "I can study the impact of new bridges, or understand how roads have evolved. The map can be used to see whether a city was planned or unplanned, or see how much distance the new Kashmir Pir Panchal tunnel has cut short. "
And for this, an up-to-date, freely available and editable map is required. Rai agrees. "It empowers citizens, " he says, giving an example. "I could use the map to highlight illegal wineshops that are located in the vicinity of schools and colleges. "
Even software app developers are harnessing the data because it is free, filled with rich detail, and be downloaded. Navigation applications like AndNav, Skobbler, Mapquest, OffMaps and MapMe. At are a few examples of apps making use of OSM. And although there has been some progress in creating an elaborate digital map of India, the OSM community can do with a few more volunteers.
MAP YOUR WAY
GPS or Global Positioning System is a satellite-based navigation system made up of a constellation of 24 earthorbiting satellites. GPS satellites circle the earth twice a day and transmit signal information to the earth. GPS receivers, used by OSM mappers, use this information to calculate the exact location of landmarks during map creation. A GPS receiver must be locked on to the signal of at least three satellites to calculate a 2D position (latitude and longitude) and track movement. With four or more satellites in view, the receiver can determine the user's 3D position (latitude, longitude and altitude).
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