Mobile Sensor

Until recently, printed maps and forms were taken to the field and the information collected was sketched as notes on the map or written down on a form. This information was entered into a GIS database after returning to the office. This method of data collection is inefficient and prone to error. With a mobile Sensors system and the support of a satellite receiver, we can take a GIS into the field with us on powerful, compact mobile computers and view, capture and update information, and then synchronize changes between the field and office (Figure 1).

Professional applications for mobile GISs are endless—utilities, forestry, environmental monitoring, field engineering, to mention a few. With the integration of systems, users are able to view each others’ locations and, for example, share field data dynamically across their organization. Specifically, the data captured with mobile GISs can be instantly checked, updated and exchanged if necessary.

A simple task-driven mobile application begins in the office. GIS data are extracted from the main database and mapped onto the mobile device to be used in the field. The updated data are uploaded after returning to the office (Figure 2a).

A high-end mobile GIS application typically runs on a powerful laptop computer, many of which provide a rich set of tools comparable to a desktop GIS application. A fast wireless connection enables direct access to maps and databases at the office, and synchronizes changes between the field and office through a web service (Figure 2b).

In cases where there is no connection to the main database in the office (e.g. a firewall makes access impossible), field edits can be synchronized later, when access to the main database is provided (Figure 2c) . A versioned transaction may take care of the situation that the same feature (in the field) is updated several times: it can compare the updates (reconciling the version edits) before transferring the feature to the main, or parent, database.