About

Increasingly, we as architects must have a greater understanding of the built environment around us, especially sites with existing or even historic building conditions. With our ever expanding tool sets, we are now able to document and capture such environments digitally in order to have accurate data that we can reference and modify in a 3D environment. Rather than taking measurements by hand we can use a combination of laser scanners and cameras (both aerial and terrestrial) in order to capture difficult site conditions and allow us to return to the site virtually as many times as we need, which can be especially useful in hard to access locations.

LiDAR

LiDAR is a surveying method that measures distance to a target by illuminating the target with laser light and measuring the reflected light with a sensor. Differences in laser return times and wavelengths can then be used to make digital 3-D representations of the target. The name LiDAR, now used as an acronym of light detection and ranging[1] (sometimes, light imaging, detection, and ranging), was originally a portmanteau of light and radar. Lidar sometimes is called 3D laser scanning, a special combination of a 3D scanning and laser scanning. It has terrestrial, airborne, and mobile applications.

LiDAR is commonly used to make high-resolution maps, with applications in geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, laser guidance, airborne laser swath mapping (ALSM), and laser altimetry. The technology is also used in control and navigation for some autonomous cars.

UT East Mall	UT Goldsmith Courtyard	UT Honors Quad

Photogrammetry

Photogrammetry is the art, science and technology of obtaining reliable information about physical objects and the environment through the process of recording, measuring and interpreting photographic images and patterns of electromagnetic radiant imagery and other phenomena.

There are many variants of photogrammetry. One example is the extraction of three-dimensional measurements from two-dimensional data (i.e. images); for example, the distance between two points that lie on a plane parallel to the photographic image plane can be determined by measuring their distance on the image, if the scale of the image is known. Another is the extraction of accurate color ranges and values representing such quantities as albedo, specular reflection, metallicity, or ambient occlusion from photographs of materials for the purposes of physically based rendering.

Close-range photogrammetry refers to the collection of photography from a lesser distance than traditional aerial (or orbital) photogrammetry. Photogrammetric analysis may be applied to one photograph, or may use high-speed photography and remote sensing to detect, measure and record complex 2D and 3D motion fields by feeding measurements and imagery analysis into computational models in an attempt to successively estimate, with increasing accuracy, the actual, 3D relative motions.

UAV

Support

• All support for Site Documentation is provided by TRIG
  • SUT 1.120
  • trig@utexas.edu 

Documentation