Civil Engineering - Advanced Surveying - Discussion

Stereoplotter: it is a three-dimensional digitizer that uses the principle of binocular vision to create a 3D model of terrain from overlapping photographs:.


Principle.

The stereoplotter's principle is based on binocular vision, where each eye sends a slightly different image of an object to the brain, which interprets the images to create a sense of depth.

Process.

The stereo plotter uses two photographs with at least 60% overlap and is corrected for distortion. The photos are placed on transparent media and projected onto a viewing system using a light source and special optics. The operator wears glasses with colour filters that match the colours of the projected images, allowing them to see the image in 3D.

Result:

The overlapping image, called an anaglyph, is a 3D model of the terrain. The operator can then use the stereo plotter's optics to plot the contours and features of the model.

Types:

There are three main types of stereoplotters: optical, mechanical, and opto-mechanical. Optical plotters are older and have an open design, while mechanical plotters are enclosed and have a more efficient viewing system.

A stereo plotter is an instrument that uses stereo photographs to determine elevations for the purpose of creating contours on topographic maps.

What is the use of stereo plotting instruments?