Engineering & Science Articles

“In this interview, we talk to Jean Sans of Experts-Yachts about the uses of photogrammetry in maritime surveys. An early adopter of the technology, Jean has been employing photogrammetry in his practice since 1983.”

Renewable energy, aside from the environmental benefits, is increasingly making economic sense. Wave energy is a viable form of renewable energy. In small-scale testing of wave energy converters (WEC), a key focus is on characterising the relationship between the primary converter and simulated power take-off system. If primary conversion is via the deformation of a flexible material, this task often requires non-contact measurement. In this paper, the authors introduce the development of an underwater non-contact measurement technique called videogrammetry, and its novel application to characterise the primary converter operation of a flexible membrane WEC.

A construction company based in North Carolina incorporates new drone photo technology with advanced software to calculate stockpile volumes quickly and efficiently, and in addition, create site topographic data.

The purpose of this project was to assess the feasibility to restore the Ely Bridge in Monticello, Iowa, a structure listed in the National Register of Historic Places. The author was invited by the Department of Civil Engineering of the University of Colorado, Denver, to create a three-dimensional scaled wire frame of the bridge to be used in a finite-element stress analysis. This report describes the effort of creating this digital three-dimensional wire frame, using photogrammetric tools. This

“At full-scale, measuring the spinnaker shape in real sailing conditions (flying shape) is also valuable for sail designers as they would benefit a feedback for their designs. Nonetheless it remains complex to measure spinnaker flying shapes partly because of their inherent instability, like flapping of the luff. This work presents a full-scale experimental investigation of spinnaker flying shapes with simultaneous measurement of the aerodynamic loads on the three sail corners, as well as navigation and wind data. The developed experimental set-up and photogrammetric method to acquire the flying shape of the spinnaker are presented”

“The reverse engineering applications has gained great momentum in industrial production with developments in the fields of computer vision and computer-aided design. The reproduction of an existing product or a spare part, reproduction of an existing surface, elimination of the defect or improvement of the available product are the goals of industrial reverse engineering applications. The first and the most important step in reverse engineering applications is the generation of the three dimensional (3D) metric model of an existing product in computer environment. The possible usage of terrestrial photogrammetry in reverse engineering application is investigated based on low cost photogrammetric system. The main aim was the generation of the dense point cloud and 3D line drawing of the ship model by using terrestrial photogrammetry. Then 3D line drawing operations, point cloud and orthoimage generations have been accomplished by using PhotoModeler software. As a result of the proposed terrestrial photogrammetric steps, 0.5 mm spaced dense point cloud and orthoimage have been generated.”

The authors describe a low-cost application of digital photogrammetry using commercially available photogrammetric software and oblique photographs taken with an off-the-shelf digital camera to create sequential digital elevation models (DEMs) of a lava dome that grew during the 2004–2008 eruption of Mount St. Helens volcano.

The authors used PhotoModeler in structural testing. A camera and PhotoModeler were used to extract information about the overall geometry of specimens, as well as the XYZ motion of select points on the structure specimens during testing.

“To what extent can terrestrial photogrammetry be used for displays andor engineering purposes? What is the state-of-the-art of the technology? What were the difficulties encountered, and how were they circumvented? These are the questions we asked as we set out to determine how best to photograph and preserve the dinosaur tracks on Dinosaur Ridge in Morrison, Colorado…”

For calibrating the camera, an accurate determination of the interior orientation parameters is needed. For more accurate results, the calibration images should be taken under conditions that are similar to the field samples.The aim of this work is the establishment of an efficient and accurate digital camera calibration method to be used in particular working conditions, as it can be found with our UAV (Unmanned Aerial Vehicle) photogrammetric projects.