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1、Summary of Polyhedral Solids 平面立体概述Prism 棱柱Pyramid 棱锥Exercise 练习题,Projection of Polyhedral Solids平面立体的投影,请点击相应标题显示其内容,Summary of Polyhedral Solids 平面立体概述,Prisms 棱柱,Intersection lines of edge planes are called edge lines.Intersection lines of edge planes and bases are called base edge lines.When draw
2、ing projections of polyhedral solids,we are actually drawing the projections of all edge lines and base edge lines followed by a visibility test of the projected edge lines and base edge lines.各棱面的交线称为棱线,棱面与底面的交线称为底边,画平面立体的投影图,实质是画出所有棱线和底边的投影,并判别其可见性。,Pyramids棱锥,Polyhedral solids 平面立体,请点击鼠标左键显示后面内容,
3、Polyhedral solids:The solids that are surrounded by planes are called polyhedral solids.平面立体:完全由平面围成的立体称为平面立体。,Class by the bases of prisms 根据棱柱底面形状可分为:,Triangular prism三棱柱,Prism 棱柱,Square prism四棱柱,Pentagonal prism 五棱柱,Hexagonal prism六棱柱,Draw steps画图步骤：,Draw centerlines and datum lines.先画中心线和基准线;Add
4、 lines for the upper and lower(end)faces.再画反映顶部或底部(端面)形状的视图;Complete three views.按三等规律画全三视图。,请点击鼠标左键显示后面内容,五棱柱的投影演示,1.Projection of a prism 棱柱的投影,Example3.Draw the pentagonal prism and get points on the surface.画五棱柱及表面上各点的三视图。,The projection of point is not visible when it is on invisible edge or pl
5、ane.凡在不可见表面及棱线上的点,其投影则为不可见。,Identification 判别:,The projection of point is also visible when it is on visible edge or plane.凡在可见表面及棱线上的点,其投影为可见;,Method 方法:,Getting points on surfaces of a prism can be based on the accumulation characteristics of edge lines or plane projection.棱柱表面上的点可利用棱线或棱面的积聚性投影求之。
6、,2.Getting points on the surface of a prism 棱柱表面上取点,Labeling 标注:,All invisible points are written in brackets.对不可见的点加括号以示区别。,请点击鼠标左键显示后面内容,Example1.Draw the triangular prism and get points on the surface.画三棱柱及表面上各点的三视图。,Example2.Draw the square prism and get points on the surface.画四棱柱及表面上各点的三视图。,Pri
7、sm 棱柱,Class by the bases of a pyramid 根据棱锥底面形状可分为:,Triangular pyramid 三棱锥,1.Projection of pyramid 棱锥的投影,Square pyramid 四棱锥,Pentagonal pyramid五棱锥,Hexagonal pyramid六棱锥,Draw steps画图步骤：,1.Draw symmetry lines and the base of the pyramid.先画锥底面形状的投影;2.Add the vertex of the pyramid.再画锥顶点的投影;3.Complete three
8、 views after adding lines for the side faces.最后画各棱线的投影。,请点击鼠标左键显示后面内容,Pyramid 棱锥,2.Getting points on the surface of a pyramid 棱锥表面取点,Draw an auxiliary line or plane going through the point on the pyramid.在棱面上过锥顶作一条包含该点的辅助线或辅助平面。,Distinguish 判别:,Labeling 标注:,All invisible points are written in bracke
9、ts.对不可见的点加括号以示区别。,请点击鼠标左键显示后面内容,Example4.Draw a regular triangular pyramid and get points on the surface.画正三棱锥及表面上各点的三视图。,Example5.Draw a regular pentagonal pyramid and get points on the surface.画正五棱锥及表面上各点的三视图。,Pyramid 棱锥,The projection of point is also visible when it on visible edge or plane.凡在可见
10、表面及棱线上的点,其投影为可见；,The projection of point is not visible when it on invisible edge or plane.凡在不可见表面及棱线上的点,其投影则为不可见。,Method 方法:,a,Exercise.Complete each drawing by adding the missing detail.补全平面立体及其表面上各点的三投影。,（1）Draw a prism and get points on the surface.画三棱柱及各点的三投影。,a,b,c,请点击解答显示其内容,(c),(b),本 小 节 结 束
11、,谢谢您的认真学习！,退出,前一页,Example1.Draw the triangular prism and get points on the surface.画三棱柱及表面上各点的三视图。,Draw view of the end faces.先画反映端面形状的视图;Complete three views.再按三等规律画全三视图;Draw all views of points.求各点的三投影。,请点击鼠标左键显示后面内容,Steps作图步骤：,a,a,(b),b,d,Example2.Draw the square prism and get points on the surfa
12、ce.画四棱柱及表面上各点的三视图。,请点击鼠标左键显示后面内容,Draw view of the end faces.先画反映端面形状的视图;Complete three views.再按三等规律画全三视图;Draw all views of points.求各点的三投影。,Steps 作图步骤：,c,d,（c),Example3.Draw the pentagonal prism and get points on the surface.画五棱柱及表面上各点的三视图。,Steps作图步骤：,（1）Draw the accumulation top view.先画有积聚性的俯视图;,（2）
13、Draw the limit elements.再画主视图各棱线的投影;,（3）Draw all views of prism.根据投影规律求第三投影;,（4）Draw all views of points.求各点的三投影。,请点击鼠标左键显示后面内容,e,e,（f),f,f,e,a b c,Steps 作图步骤：,Example4.Draw a regular triangular pyramid and get points on the surface.画正三棱锥及表面上各点的三视图。,（1）Draw the top view.先画俯视图;,（2）Draw the limit elem
14、ents.再画主视图各棱线的投影;,（3）Draw all views of pyramid.根据投影规律求第三投影;,（4）Draw all views of point D.用辅助素线法求D点的三投影;,（5）Draw all views of point E.用辅助平面法求E点的三投影。,请点击鼠标左键显示后面内容,a(c)b,d,（d),e,e,e,d,k,k,p,Example5.Draw a regular pentagonal pyramid and get points on the surface.画正五棱锥及表面上各点的三视图。,Steps 作图步骤：,1）Draw the
15、 top view.先画俯视图;,2）Draw the limit elements.再画主视图各棱线的投影。,3）Draw all views of pyramid.根据投影规律求第三投影;,4）Draw all views of point G.求G点的三投影(用棱线法)。,5）Draw all views of point F.求F点的三投影(用辅助平面法)。,请点击鼠标左键显示后面内容,g,g,（f),f,g,b(a)c(e)d,a(e)b(d)c,k,k,p,在图片上点击鼠标左键可以“暂停”或再次“播放”,在图片上点击鼠标左键可以“暂停”或再次“播放”,在图片上点击鼠标左键可以“暂停”或再次“播放”,
