Projects

Introduction

On this page I present projects that I started during and before my PhD research: Virtual Landscapes, the NESCAFE project and the model airplane photographs project....

NESCAFE – Near Sensing Camera Field Equipment

During my fieldworks I needed very detailed information of the vegetation to check the consistency of visual estimates and transect measurements of vegetation cover and composition. Therefore, I made photographs of the vegetation using a newly developed mobile camera system mounted on a (fishing) rod. This system combines high mobility in the field, flexibility of height and position, with the possibility of using digital image processing techniques and digital photogrammetry techniques on the imagery. In an additional experiment we took multiple images from slightly different camera positions (20 – 30cm shift) in order to obtain stereo images with a significant overlap, which enables us to calculate very detailed Digital Elevation Models (DEM’s) with a resolution up to 3-10cm.

A paper is in progress to present the system, the processing techniques and the application of the system. We will compare the system to conventional field sampling techniques and we will discuss the advantages of NESCAFE. The wide application field of the technique will be illustrated by three case studies in significant different research fields: vegetation sampling, derivation of soil roughness and quantification of beach morphology. Emphasis is put on the validation of the system: currently a validation is carried out by comparing the computed DEM’s to detailed laser scan results. The laser scans were made by a laser scan device of ESA-ESTEC’s Wave Interaction & Propagation Section.

 

Downloads & Links
Presentation, NESCAFE: NEar Sensing CAmera Field Equipment - Utrecht 2004		PDF
High resolution image of vegetation		JPG
High resolution image of beach morphology		JPG
Calculated 3D anaglyph image of beach morphology		JPG
ESA-ESTEC’: Wave Interaction & Propagation Section		ESA ESTEC
NESCAFE Artist impressions by "Jurjen geïllustreerd"		PDF

Model Airplane Photographs

On June 10, 2002 I carried out an experiment to take pictures from a radio-controlled model airplane operated by Henk Markies of the laboratory of Physical Geography. The model airplane was equipped with a 2MP Canon Powershot digital camera, providing a maximum resolution of 10cm depending on the flying altitude. We used a real-time video downlink to support the navigation over the area of interest. The succesful flight resulted in 80 images which were orthorectified with Leica Photogrammetry Suite (using a 25m resolution DEM) and merged to one mosaic. The experimental system can easily be equipped with compact 7MP+ cameras providing higher resolutions.

 

Downloads & Links
Video of the experimental flight: downlink from the model airplane (reduced size & quality - 340kbs)		WMV
High resolution ortho-rectified mosaic of the images		JPG
Laboratory of Physical Geography		http://www.geo.uu.nl

Virtual Landscapes

Recent research in the modelling of dynamic spatial processes has demonstrated the ability to model a wide range of dynamic geographical processes in a simple, yet satisfactory way. These geographic models can be used for teaching and instruction, although it is technically too advanced for undergraduate students in the first or second year of geography or geology. I have built a system for student instruction that enables undergraduate students to study geographical computer models, without knowledge of the technical aspects of modelling. In this system the geographical models are available through an interface. Students can run the model and view the results as graphs, maps or animations. If required they can change the parameter values and run the model again.

The Virtual Landscapes course was part of the K&S (Kwaliteit & Studeerbaarheid) programme. A user account and password are needed to access www.virtualland.geo.uu.nl. Please contact virtualland "at" geo.uu.nl if you need an access password.