Projections of straight line when inclined to both hp and. Hence, in monges projection, a straight line is represented by a pair of projections p,p. Graphical design of world map projections article pdf available in international journal of geographical information science 2411. Mercator projection, a map projection introduced by flemish cartographer gerardus mercator in 1569. Actual projections in top and front views are drawn in thick lines. Mercator projection, type of map projection introduced in 1569 by gerardus mercator. The longitude up and down lines on the robinson projection are allowed to curve while the latitude lines right to left remain straight. Projection of straight lines pdf projecting the image of an object to the plane of projection is known as. Download projections of straight lines book pdf free download link or read online here in pdf.
Lowdose radiation a critical turning radius between 1520 m differentiated turning radii with relatively high vegetation loss. On other projections straight lines are not rhumb lines. Quadrilateral projected onto the plane dx length along the x axis from a to c. Pseudoconical in standard presentation, pseudoconical projections represent the central meridian as a straight line, other meridians as complex curves, and parallels as circular arcs. A point t lies on a line p if its horizontal projection lies on the horizontal projection of the. The mercator projection is a useful navigation tool, as a straight line on a mercator map indicates a straight course, but it is not a practical world map, because of distortion of scale near the poles. This document is highly rated by mechanical engineering students and has been viewed 3280 times. The simplest position a straight line occupies in a space is, it is parallel to both v. A great circle is a straight line on a gnomonic projection. Projections of straight lines straight line it is the shortest distance between two given points. A projection of points by straight lines drawn through them from some given point to an intersection with the plane of projection.
This projection is often used by navigators to gauge distance and in seismic work because seismic waves tend to travel along great circles. This is achieved by casting surface points of the sphere onto a tangent plane, each landing where a ray from the center of the sphere passes through the point on the surface and. Great circle on a spherical earth, a great circle is the shortest distance between two locations. The general recommendation are that thick lines are twice as thick as thin lines. A straight line ab of 40 mm length has one of its ends a, at 10 mm from the hp and 15 mm from the vp. Front views of the two end points of a straight line, when joined, give the front view of the straight line.
Now that we have our dashed wedged line structure, we can convert it to a fischer projection. Tips for projection of straight linesiiinclined to both. The projections of a straight line are obtained by joining the top and front views of. Projections of straight lines pdf book manual free download. Coordinates are the average of the mollweide and equirectangular projections.
Inclination of its surface with one of the reference planes will be given. Hence, the projections of a straight line may be drawn by joining the. The following are the important positions which a straight line can take with respect to two reference planes. The above position resulting in straight line as a top view and front view. In standard presentation, pseudoconical projections represent the central meridian as a straight line, other meridians as complex curves, and parallels as circular arcs. The length of the poles and the central meridian depends on the standard parallels. A straight visible or hidden line in a sketch has 3 possible meanings. A gnomonic map projection displays all great circles as straight lines, resulting in any straight line segment on a gnomonic map showing a geodesic, the shortest route between the segments two endpoints. Hence, the projections of a straight line may be drawn by joining the respective projections of its ends which are points. Certain projections are particularly suited for representing continent sized regions of the sphere. It is a modified galls stereographic, except times has curved meridians. Location of a line the location of a line in projection quadrants is described by specifying the distances of its end points from the vp, hp and pp. List of map projections wikimili, the free encyclopedia. A straight line is the shortest distance between two points.
Engineering graphics projections of a straight line. Different surfaces and planes form the configuration or shape of any object. Directions are true only from the center point of projection. In standard presentation, conic or conical projections map meridians as straight lines, and parallels as arcs of circles. Projections of planes in this topic various plane figures are the objects. A thick continuous line is used for visible edges and outlines. Nov 03, 2014 top views of two end points of a straight line, when joined, give the top view of the straight line. College football odds, picks, lines, spreads for 201920. Hence, when a line is parallel to a plane, its projection on the plane is equal to its true. College football odds, picks, lines, spreads for 201920 bowl games. Mercators projection is conformal preserving angles and infinitesimal shapes. However, before we can convert this dashedwedged line structure into a fischer projection, we must first convert it to a flat dashedwedged line structure. Projection of straight lines in engineering graphics pdf.
Draw the projections of the line if it is parallel to the vp and inclined at 30 to the hp. Fundamental development surfaces and linespoints of zero distortion plane or gnomic projection. Projections of a straight line introduction the shortest distance between any two points is called a straight line. Top views of two end points of a straight line, when joined, give the top view of the straight line. All books are in clear copy here, and all files are secure so dont worry about it.
After transforming the map to an equalarea projection in this case mollweide, which also preserves straight lines of latitude its obvious that most of the northern hemisphere remains snow and ice free, even in midwinter. Perspective projection article about perspective projection. In particular, the twostandard and polystandard conic projections are much favoured in atlases of the world. If one visualises the projection surface as a piece of paper which touches the generating globe at a certain point or along certain lines, then these lines or points where the two surfaces touch will be distortion free. This site is like a library, you could find million book here by using search box in. Apr 22, 2020 projections of straight lines ppt, engineering drawing, semester mechanical engineering notes edurev is made by best teachers of mechanical engineering. A method of projection in which a threedimensional object can be represented by projecting points upon a picture plane using straight lines converging at a fixed point, representing the eye of the viewer. The top and front views of the line have lengths of 55mm and 70mm respectively. Read online projections of straight lines book pdf free download link book now. Lowdose radiation a critical turning radius between 1520 m differentiated turning radii with relatively high vegetation loss as compared to straight line tracking. These are then known as lines or points of zero distortion. Projections of straight lines ppt, engineering drawing. Projections of straight lines pdf book manual free.
Draw the projections of the line and find its true inclinations with the vp and the hp. Projections of straight lines ppt, engineering drawing, semester mechanical engineering notes edurev notes for mechanical engineering is made by best teachers who have written some of the best books of mechanical engineering. Proven model reveals best predictions sportslines advanced computer model simulated every college football bowl game 10,000 times. Perspective projection a method of projection in which a threedimensional object can be represented by projecting points upon a picture plane using. Added lines depicting rounded and filleted edges, as shown in figs. Figures a and b below show similar examples of a narrow prism. Central meridian and all parallels are straight lines. Straight line locus of a point, which moves linearly the shortest distance between any two given points. Other projections show great circle routes as straight lines, making it easy to figure out the shortest distance between two. Projections of straight lines mid point problem duration. The straight lines crossing at right angles of this map projection make it useful for navigation, but it distorts the size of areas away from the equator.
The sphere and the plane touch at the tangent point. Parallels are straight lines increasing in separation with distance from the. Line ab 75mm long makes 45 0 inclination with vp while its fv makes 55. A line ef, 85mm long has its end e, 25mm above the hp and 20mm in front of the vp.
Projection of lines free download as powerpoint presentation. To draw the projections of a straight line located at different positions with respect to the vp and the hp. These letters are used to represent a point, ends of a straight line, corners of a probability measures on metric spaces pdf solid, etc. These projections also have radial symmetry in the scales and hence in the distortions. The end a is 12 mm in front of the vp and 15 mm above hp. Thus the shortest path between two points in reality corresponds to that on the map.
Assume the line to be located in each of the four quadrants by turns. A thin line is used for hatching, leader lines, short centre lines, dimensions and projections. The times projection was developed by moir in 1965 for bartholomew. Since meridians lines of longitude and the equator are great circles, they are always shown as straight lines on a gnomonic map. Parallel to one plane and perpendicular to the other. A map showing just the northern hemisphere azimuthal equal area, centered on the north pole makes is yet more clear. Projection of straight lines ii line geometry angle. This is achieved by casting surface points of the sphere onto a tangent plane, each landing where a ray from the center of the sphere passes through the point on the. Projections of straight line when inclined to both hp and vp example3.
Projections of straight line when inclined to both hp and vp. Azimuthal in standard presentation, azimuthal projections map meridians as straight lines and parallels as complete, concentric circles. Adaptive composite map projections geovisualization. The second set of top views, where lines are added to.
In engineering drawing practice two principal planes are used to get the. Azimuthal projections have the property that directions from a central point are preserved and therefore great circles through the central point are represented by straight lines on the map. Revolving or moving straight lines in different ways obtains these surfaces and planes. Consider the distance between the longitude and latitude lines. Aug 06, 2019 the downsides of cylindrical map projections are that they are severely distorted at the poles.
As with all cylindrical projections, the parallels and meridians form a grid of straight and perpendicular lines. A straight line 55 mm long makes an angle of 30 deg to the hp and 45 deg to the vp. A false, straight line interpolation of bionegative health effects from high dose effects was the basis for this hypothesis. Meridians are equally spaced curves, curving toward the central meridian. A straight line may have different orientations in space well be positioning this line in different ways that is it may be parallel or inclined to. Engineering graphics projection of points and lines. Great circles transform to straight lines via the gnomonic projection. A false, straightline interpolation of bionegative health effects from high dose effects was the basis for this hypothesis. You can get this from a straight line on a mercator projection. The blue atoms are in the plane of the screen so they are designated with straight lines.
The eckert iv and vi projections, presented by the german cartographer max eckertgreiffendorff in 1906, are pseudocylindrical equalarea projections. Shows longitude and latitude as straight lines that follow compass shows all the lines of longitude and latitude as straight lines. They make air and ship navigation easy, because you just have to draw a straight line, point your ship in that direction, and start sailing. Projection of straight lines ii free download as powerpoint presentation. Some projections, like the mercator above, show loxodromes as straight lines. The downsides of cylindrical map projections are that they are severely distorted at the poles. Multipoint perspective will not be covered in this lessondepends on the number of vanishing points in the perspective drawing onepoint. This is the reason the mercator projection was invented. If line is in 1 st quadrant draw its projections and find its inclination with hp. The shortest distance between any two points is called a straight line. The meridians are equally spaced parallel vertical lines, and the parallels of latitude are parallel horizontal straight lines that are spaced farther and farther apart as their distance from the equator increases. Draw the straight lines from picture plane every corner of the box to the convergence lines. In particular, the twostandard and polystandard conic projections are. Project the added lines from the intersections of the surfaces as if the rounded and filleted were not present.
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