Land Demarcation Using Low-Cost Mobile Georeferenced Devices

Abstract

Territory demarcation is an activity done by man for thousands of years. Since wherever, there was a need of each individual or people define their property, so that they can exploit its resources or even to take the advantages of the terrain positioning. In developed countries this process runs quite naturally with the help of specialised teams and cutting edge equipment. However, in developing countries, such as sub-Saharan Africa, this process is much more costly, in both time and money. Being a much more time-consuming process due to lack of infrastructure, support of local governments, the lack of access to recent technology or the lack of skilled workers. The main objectives to achieve with this dissertation is rethink the way the territory demarcation process is done using only low cost mobile devices that can be used and accessed by anyone, thus removing the need for specialised staff to perform the task. This solution requires developing a mobile application that makes this whole process, along with a server with GIS capability that should be able to assist and serve as a tool of analysis of the whole process. Solutions to minimise the error in the obtained demarcation have been studied, making use of all available localisation data in a mobile device, the GPS receiver and also the data provided by the device sensors. A prototype that demonstrates that this solution can replace the current territory demarcation systems in those countries was created. Several tests were executed to demonstrate that it is possible to successfully demarcate terrains and property, with more or less precision. This precision is very connected to signal quality at the time of capture of the points. To minimise this influence an algorithm has been developed that uses information provided by more than one device to complete the demarcation. The use of all the available information in a mobile device to demarcate land, opens doors for demarcations with adequate precision, but if the result does not meet the expectations, it is also possible to make manual corrections, either in the mobile application as in the Web application.