Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

True Sizes: Folding Method in Descriptive Geometry

Description

This lecture covers the folding method in descriptive geometry, focusing on true sizes of segments and distances between points. It explains the concept of orthogonal and parallel projections, conservation of alignment, and properties of space quantities. Through examples, the instructor demonstrates how to construct true magnitudes of segments using projections and folding techniques.

Official source

Ontological neighbourhood

Civil engineering

Architectural engineering: Technical drawing

Related concepts (32)

3D projection

A 3D projection (or graphical projection) is a design technique used to display a three-dimensional (3D) object on a two-dimensional (2D) surface. These projections rely on visual perspective and aspect analysis to project a complex object for viewing capability on a simpler plane. 3D projections use the primary qualities of an object's basic shape to create a map of points, that are then connected to one another to create a visual element.

Orthographic projection

Orthographic projection (also orthogonal projection and analemma) is a means of representing three-dimensional objects in two dimensions. Orthographic projection is a form of parallel projection in which all the projection lines are orthogonal to the projection plane, resulting in every plane of the scene appearing in affine transformation on the viewing surface. The obverse of an orthographic projection is an oblique projection, which is a parallel projection in which the projection lines are not orthogonal to the projection plane.

Map projection

In cartography, a map projection is any of a broad set of transformations employed to represent the curved two-dimensional surface of a globe on a plane. In a map projection, coordinates, often expressed as latitude and longitude, of locations from the surface of the globe are transformed to coordinates on a plane. Projection is a necessary step in creating a two-dimensional map and is one of the essential elements of cartography. All projections of a sphere on a plane necessarily distort the surface in some way and to some extent.

Mercator projection

The Mercator projection (mərˈkeɪtər) is a cylindrical map projection presented by Flemish geographer and cartographer Gerardus Mercator in 1569. It became the standard map projection for navigation because it is unique in representing north as up and south as down everywhere while preserving local directions and shapes. The map is thereby conformal. As a side effect, the Mercator projection inflates the size of objects away from the equator. This inflation is very small near the equator but accelerates with increasing latitude to become infinite at the poles.

Equirectangular projection

The equirectangular projection (also called the equidistant cylindrical projection or la carte parallélogrammatique projection), and which includes the special case of the plate carrée projection (also called the geographic projection, lat/lon projection, or plane chart), is a simple map projection attributed to Marinus of Tyre, who Ptolemy claims invented the projection about AD 100. The projection maps meridians to vertical straight lines of constant spacing (for meridional intervals of constant spacing), and circles of latitude to horizontal straight lines of constant spacing (for constant intervals of parallels).

Related lectures (43)

Mechanical Design Principles: Technical Drawing and Projections

Introduces mechanical design principles, focusing on technical drawing and projection methods essential for accurate representation in engineering.

Geometric Representation: Introduction to Descriptive Geometry

Covers the basics of descriptive geometry and the method of Monge for spatial representation.

Geometric Projections: Orthogonal and Monge Projections

Covers orthogonal and Monge projections in descriptive geometry, focusing on geometric properties and visualization techniques.

Introduction to Rhino Surfaces and Meshes

Introduces working with surfaces, polysurfaces, and solids in Rhino, covering rendering, material editing, and mesh creation.

Mechanical Design Principles: Projections and Representations