Mapping for Engineering Surveying and GIS Practical;
Aims and Objectives:
To design experiments and undertake a comparison of results and products; a. Aerial triangulation assessment of limitations and benefits of airborne GPS and a comparison of camera calibration models. b. Comparison of 3D vector data collection using Stereo Analyst and ArcGIS with 3D vector data collection using the ortho-image. c. Comparison of digital surface models (DSMs) produced by photogrammetry with airborne laser scanning (Lidar). d. Comparison of building modelling techniques produced by close range photogrammetry with mobile laser scanning.
Assessment:
Poster (Typically this should include; design of the experiments, how the experiment was performed (methodology), the results and their evaluation, critical review of methods, any other comments). The poster should be a PowerPoint (digital) poster (A0 size – 1189x841mm landscape).
Do not try and overload the poster with text or images, remember a poster should be read from about 2-3m away so small text and diagrams should be avoided. You might like to look at the specification given to presenters at international conferences, this is an example from the International Society for Photogrammetry and Remote
Sensing; https://www.isprs.org/documents/orangebook/app6.aspx .
Methodology and equipment
• ERDAS Imagine & Leica Photogrammetry Suite to be used for Aerial Triangulation, DSM extraction and Orthophoto production
• ERDAS Imagine and Stereo Analyst to be used for vector data collection from stereo pair of aerial images • ArcGIS to be used for the collection of vector data from
Orthophoto:
• For objective a, b and c the same project area and date as provided in Project 1
• For objective a appendix B gives some suggestions.
• For objective b give some thought about the parameters you should use in the comparison. These should be the important characteristics e.g. speed of data collection,
Correctness of position…
• For objective c the airborne laser scanning data will be provided. o Give thought to the resolution of the data (spacing of points) and the measurement quality of the data. You will have to consult manufacturers and/or published documents to find the quality of Lidar data.
• For objective d consider the following tasks: o A DSM from mobile laser scanning will be provided.
To create the 3D computer model of the building using close-range photogrammetry you will need to collect digital camera images of the façades of the building and use
Photomodeller to create the model.
1. A digital SLR camera (or your own) will be used to collect a series of photographs around the Exchange building, Jubilee Campus. The camera calibration process within Photomodeller will be discussed.
2. The processing of the images using Photomodeller can then be undertaken. A separate hand out will be provided to guide you through this process.
Documentation and tutorials
• An Introduction to 3D Building with stereo analyst.doc
• An Introduction to 3D modelling with Photomodeler.doc
• Texture_mapping_and_visualization.doc
• Introduction to 3D Modelling from Laser Scanning data with Geomagic Studio emergency services