Executive Summary : | Objective: Landslides are one of the major natural hazards that produce enormous property damage each year during monsoon season involving both direct and indirect costs. Landslides never occur all of a sudden; they pose pre-cursor signatures on the surface in terms of topographical and geomorphological changes. All such processes are very often not possible to map and monitor through ground-based surveys such as field trekking, instrumentation and monitoring etc. along with other associated issues of maintenance of ground-based monitoring systems. To overcome such issues, multitemporal optical imaging using unmanned aerial vehicle (UAV) such as Drone can be a better alternative to monitor the precursor phenomena on the surface relating to topography and geomorphology of hill slopes during monsoon seasons with a vision to predict and warn before a major landslide disaster. Summary: The objective of the project is to test the applicability of an optical-imaging-sensor drone for the temporal mapping, characterizing and monitoring of landslide hazard prone areas in Indian Himalayas during monsoon period for the purpose of early warning to save lives of people in difficult hilly terrain. In the process, multi-temporal acquisition, real-time processing and comparison of drone based optical imaging data sets will be performed to understand the definition of the evolution of landslides. The positional change (geographical coordinates along with altitude) of topographical and geomorphological features (in particular fissures, tension cracks, prominent ground objects etc.) could be considered for a multi-temporal analysis with the aim of the characterization of the landslide kinematics and evolution. Multi-temporal image correlation and change detection techniques will also support to improve this approach in terms of defining the surface movement of landslides. Further, digital surface models (DSMs) and digital terrain models (DTMs) can be generated from the high density point clouds and used for multi-temporal analysis The comparison of DSMs/DTMs can be used for the determination of volumetric changes caused by the evolution of the landslide. This also can be helpful in determining the rate of movement/displacement of the detached mass of the landslide, based on which prediction for early warning of a catastrophic landslide can be made. Under the scope of the project, a facility of “Mobile Van equipped with Drone based Landslide Warning System” will be created. This mobile van will be equipped with a drone with on-board optical imaging sensor, computational facilities with data acquisition and post-processing softwares, on-board GPS and other accessories. |