Does Coimbra Need a 3d Cadastre? Prototyping a Crowdsourcing App As a First Step to Finding Out

Abstract

ABSTRACT:The Municipality of Coimbra in Portugal, and indeed the country as a whole, is currently undergoing a long-term land registration (cadastre creation) exercise, with approximately 50% of the country having been surveyed, amounting to 1/3 of the total properties, by the end of 2013. The survey process is currently generating two-dimensional (2D) maps. However, as with many other countries, these maps have limitations when representing the real three-dimensional (3D) complexities of land and property ownership. Capturing 2D cadastre is an expensive process, and does not provide the required insight into the number of properties where the ownership situation is inadequately represented, as the survey does not include the internal building structure. Having information about the extent of the 2D/3D issue is, however, fundamental to making a decision as to whether to invest resources in even more expensive 3D survey. Given that the 3D complexity inside buildings is only known to residents/occupants -thus making crowd sourcing perhaps the only economically feasible approach for its capture -this paper describes the development of a web-based App envisaged for use by the general public to flag different land and property ownership situations. The paper focuses on two aspects of the problem -firstly, identifying an appropriate, clear, set of diagrams depicting the various different ownership situations from which the user can then pick one, and secondly prototyping and user testing an App for multi-platform VGI data capture in absence of direct feedback from the final end users -i.e. the general public.

A Prototype Machine Learning Tool Aiming to Support 3D Crowdsourced Cadastral Surveying of Self-Made Cities

“…It is now accepted that a cadastral system may be comprised of various datasets of variable quality integrated together in a fit-for-purpose whole [43]. In recent years, data collection methods such as VGI and crowdsourcing techniques have claimed a place as a reliable cadastral data source, strengthening their role in the process for the initial implementation of 2D and 3D cadastre in both the developing and the developed world [25,36,37,40,41,[43][44][45][46][47][48][49][50]. To date, much research has been carried out trying to manage the 3D aspect of the physical objects and introduce crowdsourcing in 3D cadastral surveying procedures.…”

“…Ref. [50] proposed an interesting web-based crowdsourced approach, enabling the contributor to identify and choose the ownership situation that responds to his/her proprietary situation, through a set of alternative sketches depicting different types of land and property ownership situations. The contributor may also submit additional data concerning the location of the declared property (address, post code, point on a map), legal documents proving his/her rights and additional comments concerning the cadastral case.…”

A BIM-IFC Technical Solution for 3D Crowdsourced Cadastral Surveys Based on LADM

“…Ellul et al [52], present an interesting crowdsourced approach that aims to collect information regarding the land and property ownership situation. They developed a web-based application that enables the user to select his/her situation from several groups of ownership situations sketched out by the research team.…”

Indoor Localization for 3d Mobile Cadastral Mapping Using Machine Learning Techniques

“…Research on this topic has focused on the investigation of applying the existing 2D experience in 3D cadastral surveys. Ellul et al (2016) proposed the development of a web-based application that was intended to be used by the general public for the identification of the various land and property ownership situations. The user of the application is asked to select his/her situation from several groups including different types of land ownership, which where sketched by the research team.…”