3GPP TR 36.873 V1.0.0 (2013-09)
Technical Report
3rd Generation Partnership Project;
Technical Specification Group Radio Access Network;
3D channel model for LTE
(Release 12)
The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP. The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented.
This Report is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Specification. Specifications and Reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners' Publications Offices.
MCC selects keywords from stock list.
Keywords
3GPP
Postal address
3GPP support office address
650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Internet
https://www.doczj.com/doc/a410801839.html,
Copyright Notification
No part may be reproduced except as authorized by written permission.
The copyright and the foregoing restriction extend to reproduction in all media.
? 2011, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).
All rights reserved.
UMTS? is a Trade Mark of ETSI registered for the benefit of its members
3GPP? is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners LTE? is a Trade Mark of ETSI registered for the benefit of its Members a nd of the 3GPP Organizational Partners GSM? and the GSM logo are registered and owned by the GSM Association
Contents Foreword (4)
1Scope (5)
2References (5)
3Definitions, symbols and abbreviations (5)
3.1Definitions (5)
3.2Symbols (5)
3.3Abbreviations (5)
4Introduction (6)
5General (6)
6Scenarios for UE specific elevation beamforming and FD-MIMO (6)
73GPP evaluation methodology needed for Elevation Beamforming and FD-MIMO evaluation (7)
7.1Antenna modelling (7)
7.2Pathloss modelling (9)
7.3Fast fading model (11)
8Simulation results (12)
Annex A: (Informative) Change history (13)
Foreword
This Technical Report has been produced by the 3rd Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
1 Scope
The present document captures the findings of the study item “Study on 3D-channel model for Elevation Beamforming and FD-MIMO studies for LTE” [2]. The purpose of this TR is to help TSG RAN WG1 to properly model and evaluate the performance of physical layer techniques using 3D channel models.
This document relates to the 3GPP evaluation methodology and covers the modelling of the physical layer of both Mobile Equipment and Access Network of 3GPP systems.
This document is intended to capture the scenarios relevant to 3D channel models and the modifications to the 3GPP evaluation methodology needed to support 3D channel modelling.
This document is a …living? documen t, i.e. it is permanently updated and presented to TSG-RAN meetings.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TD RP-122034: "Study on 3D-channel model for Elevation Beamforming and FD-MIMO
studies for LTE".
[3] 3GPP TR 36.814 (V9.0.0): "Further Advancements for E-UTRA, Physical Layer Aspects".
3 Definitions, symbols and abbreviations
Delete from the above heading those words which are not applicable.
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [x] and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [x].
3.2 Symbols
For the purposes of the present document, the following symbols apply:
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [x] and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [x].
FD-MIMO Full Dimension MIMO
4 Introduction
At 3GPP TSG RAN #58 meeting the Study Item Description on “Study on 3D-channel model for Elevation Beamforming and FD-MIMO studies for LTE” was approved [2]. This study item covers the identification of scenarios applicable to 3D beamforming, FD-MIMO and the evaluation methodology needed for modelling and evaluation of such techniques. This technical report documents the modified evaluation methodology including 3D channel models needed for studying the above techniques.
5 General
[NOTE: This section will include general information that is helpful for understanding the TR and for completeness of the TR]
6 Scenarios for UE specific elevation beamforming and
FD-MIMO
[NOTE: Intended to identify the typical usage scenarios of UE-specific elevation beamforming and FD- MIMO] Scenario 3D-UMi: Urban Micro cell with high (outdoor/indoor) UE density
?Base station is below surrounding buildings
Scenario 3D-UMa: Urban Macro cell with high (outdoor/indoor) UE density
?Base station is above surrounding buildings
Table 1: Description of scenarios
2D2D-out
2)Assumptions in SECTION-2 are for calibration purposes only in this SI. Assumptions in SECTION-2 are to be
revisited for evaluating relative performance of proposed solutions in future SIs
Other typical usage scenarios of UE-specific elevation beamforming and FD- MIMO are noted below: Heterogeneous Networks
?Channel models developed for Urban Micro cell with high UE density and Urban Macro cell with high UE density scenarios shall support heterogeneous deployment scenarios.
–It is assumed that for heterogeneous deployment scenarios the macro BS height is at 25m and the lower-power node is at 10m height.
–The carrier frequency(s) for a macro can be 2 or 3.5 GHz or both if multiple carriers are used.
The carrier frequency(s) for a low power node can be 2 or 3.5 GHz or both if multiple carriers are
used.
–The transmission power of a low power node can be 30/33 dBm for 10/20 MHz.
Urban micro/macro homogeneous networks with high UE density (similar to 3D-UMi/3D-UMa) using higher than 2 GHz carrier frequency
?The carrier frequency can be 3.5 GHz.
7 3GPP evaluation methodology needed for Elevation
Beamforming and FD-MIMO evaluation
[NOTE: The study will consider as a starting point the ITU channel model as described by the combination of A2.1.6 and Annex B in 36.814 [3] and determine the additions that are needed to properly model the elevation dimension of the channel to fit the elevation beamforming and FD-MIMO purposes]
The applicable range of the 3D channel model is at least for 2-3.5 GHz.
7.1 Antenna modelling
?2D planar antenna array structure is the baseline, i.e., antenna elements are placed in the vertical and horizontal direction as below, where N is the number of columns, M is the number of antenna elements with the same
polarization in each column.
?Antenna elements are uniformly spaced in the horizontal direction with a spacing of d Hλ and in the vertical direction with a spacing of d Vλ.
(0,0)
(0,1)
(0,N-1)
(M-1,N-1)
……
(M-1,0)(M-1,1)
(1,0)
(1,1)
(1,N-1)
……
……
……
……
……
……
Figure 1:2D planar antenna structure where each
column is a cross-polarized array
(0,0)
(0,1)
(0,N-1)
(M-1,0)(M-1,1)
(M-1,N-1)
(1,0)
(1,1)
(1,N-1)
……
……
……
……
……
……
……
Figure 2: 2D planar antenna structure where each
column is a uniform linear array
Table 2: Antenna modelling parameters
where m =1,…,K. is the
7.2
Pathloss modelling
The pathloss models can be applied in the frequency range of 2 – 6 GHz and for different antenna heights. The pathloss models are summarized in Table 3 and the distance definitions are indicated in Figure 3 and Figure 4.
Figure 3: Definition of d 2D and d 3D for outdoor UEs.
Figure 4: Definition of d 2D -out , d 2D -in and d 3D -out , d 3D -in for indoor UEs .
Table 3: Pathloss models
BP BS UT c c
free space, and h’BS and h’UT are the effective antenna heights at the BS and the UT, respectively. In 3D-UMi scenario the effective antenna heights h’BS and h’UT are computed as follows: h’BS= h BS–1.0 m, h’UT= h UT–1.0 m, where h BS and h UT are the actual antenna heights, and the effective environment height is assumed to be equal to 1.0m.
2) PL
= basic path-loss, PL3D-UMi= Loss of 3D-UMi outdoor scenario, PL tw= Loss through wall, PL in= Loss inside, d2D-in is b
assumed uniformly distributed between 0 and 25m.
3) Break point distance d’
= 4 h’BS h’UT f c/c, where f c is the centre frequency in Hz, c = 3.0?108 m/s is the propagation velocity in BP
free space, and h’BS and h’UT are the effective antenna heights at the BS and the UT, respectively. In 3D-UMa scenario the effective antenna heights h’BS and h’UT are computed as follows: h’BS = h BS–h E, h’UT = h UT–h E, where h BS and h UT are the actual antenna heights, and the effective environment height h E is a function of the link between a BS and a UT. h E=1m with a probability equal to
p(d2D,h UT) and TBD otherwise.
4)PL3D-UMa-LOS = Pathloss of 3D-UMa LOS outdoor scenario.
5) PL
= basic path-loss, PL3D-UMa= Loss of 3D-UMa outdoor scenario, PL tw= Loss through wall, PL in= Loss inside, d2D-in is b
assumed uniformly distributed between 0 and 25m.
The line-of-sight (LOS) probabilities are given in
Table 4: LOS probabilities
2D-out LOS
7.3 Fast fading model
The radio channels are created using the parameters listed in TBD. The channel realizations are obtained by a step-wise procedure illustrated in Figure 5 and described below. It has to be noted that the geometric description covers arrival angles from the last bounce scatterers and respectively departure angles to the first scatterers interacted from the transmitting side. The propagation between the first and the last interaction is not defined. Thus, this approach can model also multiple interactions with the scattering media. This indicates also that e.g., the delay of a multipath component cannot be determined by the geometry. In the following steps, downlink is assumed. For uplink, arrival and departure parameters have to be swapped.
Figure 5: Channel coefficient generation procedure
General parameters:
Step 1: Set environment, network layout, and antenna array parameters
a)Choose one of the scenarios (3D-UMa, 3D-UMi)
Large scale parameters:
Step 2: Assign propagation condition (LOS/NLOS)
Step 3: Calculate pathloss
Step 4: Generate correlated large scale parameters, i.e. delay spread, angular spreads, Ricean K factor and shadow fading term
Small scale parameters:
Step 5: Generate delays
Step 6: Generate cluster powers
Step 7: Generate arrival angles and departure angles for both azimuth and elevation
Step 8: Coupling of rays within clusters for both azimuth and elevation
Step 9: Generate XPRs
Coefficient generation:
Step 10: Draw initial random phases
Step 11: Generate channel coefficients
Step 12: Apply pathloss and shadowing
8 Simulation results
[NOTE: This section will include baseline simulation results (corresponding to a number of antenna ports and transmission scheme supported by Rel-11) with the modified evaluation methodology]
Annex A: (Informative) Change history
◆由三维实体生成三视图和轴测图简要步骤 1、将三维模型以二维线框显示。 2、进入图纸空间 可选择打印设备、图纸大小，或不选任何选项，按“确定”后，生成一个浮动视口。 删除该浮动视口。 重新设置四个浮动视口：主视、俯视、左视、西南轴测图。 3、创建实体轮廓线 方法见教材P284 4.创建实体轮廓，对四个视口的图形均进行创建实体轮廓的操作 自动生成PH-XX和PVX-X八个图层 4、调整显示在视口中视图的比例 命令：mvsetup↙ 输入选项 [对齐(A)/创建(C)/缩放视口(S)/选项(O)/标题栏(T)/放弃(U)]: s↙ （缩放视口：调整对象在视口中显示的缩放比例因子。缩放比例因子是边界在图纸空间中的比例和图形对象在视口中显示的比例之间的比率。）选择所有视口 设置视口缩放比例因子为：<统一(U)>: 5、将自动生成的前三个PH-XX图层的线型设置成dashed，并修改颜色。 将轴测图的PH-XX图层关闭（一般最后生成轴测图，因此是最后一个PH-XX 图层）。 6、关闭或冻结0层 7、绘制中心线、调整线型比例等 8、标注尺寸（与二维标注方式相同） ◆构建场景的简要步骤 注：所有尺寸仅用于方便作图，做作业时不必标注。 一、台阶 1、绘制台阶平面图，见图1
图1 2、实体拉伸命令制作台阶，相邻两个台阶的高度为25，如图2 图2、 3、布尔并集将各台阶合成一个实体，见图3 图3 二、制作建筑主体
1、新建UCS，如图4 图4 2、制作内空的长方体 （1）用实体长方体命令制作，尺寸长、宽、高为：800,800,450，见图5。 （2）在此长方体内再作长方体，尺寸：长、宽、高为700、700、450，见图6。（3）再用布尔差减去中间长方体。 图5
第15章由三维实体生成二维视图 ◆15.1 概述 ◆15.2 由三维实体生成三视图 ◆15.3 由三维实体创建剖视图
15.1 概述基本视图：实体模型 在投影面投影所得到的图形称为基本视图，通常可分为主视图、俯视图、左视图、右视图、仰视图、后视图。图15-1所示的是三维零件图在各个方向的投影视图所得的效果。 (a) 三维视图 (b) 主视图(c) 后视图(d) 俯视图(e) 仰视图(f) 左视图(g) 右视图 图15-1 各个视图
剖视图：假想用一个剖切平面将三维实体剖开，移去观察者和剖面之间的部分，而将留下的部分向投影面投影，所得视图称为剖视图。 剖面图：也叫断面图，假想用剖切面将零件的某处切断，紧画出其断面的图形，称为剖切图。分为移出断面图和重合断面图。 图15-2是剖视图和剖面图的比较。 (a) 阶梯轴(b) 剖面图(c) 剖视图 图15-2 剖面图和剖视图
模型空间是为创建三维模型提供一个广阔的绘图区域，用户可以通过建立UCS，创建各种样式的模型并设置观察视点和消隐、渲染等操作。 而布局空间是用于创建最终的打印布局，是图形输出效果的布置，用户不能通过改变视点的方式来从其他角度观看图形。 它们的主要区别标志是坐标系图标。模型空间中，坐标系图标是一个反映坐标方向的坐标架，而布局空间中，坐标系图标则是三角板形状。利用布局空间可以把在模型空间中绘制的三维模型在同一张图纸上以多个视图的形式排列并打印出来，而在模型空间中则无法实现这一点。
15.2 由三维实体生成三视图 AutoCAD将三维实体模型生成三视图的方法大致有两种： 第一种方法是先使用VPORTS或MVIEW命令，在布局空间中创建多个二维视图视口，然后使用SOLPROF命令在每个视口中分别生成实体模型的轮廓线，以创建二维视图的三视图。 第二种方法是使用SOLVIEW命令后，在布局空间中生成实体模型的各个二维视图视口，然后使用SOLDRAW命令在每个视口中分别生成实体模型的轮廓线，以创建二维视图的三视图。下面分别介绍各个命令的使用。
AutoCAD中由三维图转成三视图（二维图）——附视频文件 本文主要介绍利用AutoCAD2000强大的图纸布局功能，把用户已经绘制了三维模型生成三视图。当切换到图纸空间后，AutoCAD在屏幕上显示一张二维图纸，并自动创建一个浮动视口，在这个视口中显示出已经绘制的三维模型，可根据三维模型轻易地创建多种形式的布局。用户可以调整视口视点以获得所需的主视图，然后再用SOLVIEW命令生成其他视图，如正交视图、剖视图、斜视图等。 下面将通过实例来介绍由三维模型生成三视图的技巧，并着重介绍标准的主视图、左视图、俯视图、剖视图生成方法。 1．利用三维模型创建各视图的视口 1．1 主视图视口的创建 下一步中，我们将打开已经绘制好的三维模型。首先形成模型的主视图视口，并将它布置在“图纸”的适当位置。 1）打开磁盘上的文件“机架.dwg”。 2）从模型空间切换到图纸空间。单击图形绘图窗口底部的选项卡layout1，打开[Page Setup-Layout1]对话框，然后在“Paper size”下拉列表中设定图纸幅面为“ISO A2 (594.00×420.00mm)”，单击OK按钮，进入图纸空间。AutoCAD在A2图纸上自动创建一个视口。 注意：可以把浮动视口作为一个几何对象，因此能用MOVE、COPY、SCALE、STRETCH等命令及界标点编辑方式进行编辑。 3）选择浮动视口，激活它的界标点，并进入拉伸模式，然后调整好视口大小。单击状态栏的PAPER按钮，激活浮动视口，再执行下拉菜单View→Zoom→All或标准工具条中的？？按钮，使模型全部显示在视口中，如图1所示。 4）设置“前视点”。执行下拉菜单View→3D Views命令，选择适当的视口方向，就可获得了主视图的视口，如图2所示。 1．2 左视图及俯视图视口的创建 下面根据主视图视口创建左视图及俯视图的视口。 1）执行下拉菜单Draw→Solids→Setup→View，或在Solids工具条？？按钮，在命令状态行提示下，键入ortho或o。接下来指定视口的投影方向，如图3，选择浮动视口的A边（在创建俯视图视口时选择B边），同时出现一条十字橡皮线，然后拉动十字橡皮线在主视图的右边（在创建俯视图视口时在主视图的下边）单击一点指定左视图的位置。此时无须精确调整视图的位置，因为以后还可以再调整视图的位置。 2）下一步，确定视口的大小。如图3，单击左视图的左上方的任一位置点1处（在创建俯视图视口时单击点3处），再单击左视图的右下方的任一位置点2处（在创建俯视图视口时单击点4处）。 3）最后，输入视图名称为剖视图。键入回车结束命令。
下面是“三维实体转三视图”的详细图解： 1.要将二维实体用三视图来出图，首先要画好二维立体图。第一步，不管是像现在这样的着色图…… 2.还是像现在这样的消隐图……
3.都要转换到“二维线框”模式，原因是要显示所有线条，包括因阻挡但实际存在的线条，以备以后有用。 4.在正式转三视图之前，先把出图的纸张格式定好，包括纸张横式/竖式，是否黑白打印…… 5.打印设备设置
6.打印布局设置 7.点击“设置视图”命令，或在命令行中输入solview,这个命令在布局里创建每个视图放置可见线和隐藏经线的图层（设置视图命令）
8.界面自动转到而已窗口，删除自动生成的布局。方法：点击外围的框线，实线变虚，Delete就删除了，点击Esc键，退出刚才的命令。 9.界面变成了完全的空白，再点击“设置视图”按钮，这回是正式开始设置视图了。
10.在布局里，点击鼠标右键，弹出菜单。选择UCS 11.因第一个出现的是俯视图，一般是放在左下角，因此在布局1/4的左下角中部为视力中心。 第一选项，选默认（直接回车） 第二选项，不知道比例，直接回事即可。 第三选项，指定视图中心，在布局中大概位置点击一下（点击后，如果觉得位置不好，还可以进行一次选择，点击第2次）
12.指定视图中心（点击鼠标左键后），即出现俯视图，由于我们事先没有指定比例，因此出现的俯视图根据原三维图的大小，可能会很大，也许会很小。我们只要及时滚动鼠标的滚轮还调节大小，在调节大小的同时，还可以点击鼠标的左键来调整视图的中心位置。 13.调整完成后，点击鼠标的右键或回车，命令要求指定俯视图视口的大小，方法和画矩形一样，从一个角到对角。
三视图自动生成机设计说明书 长春工程学院 2013年12月1日
目录 一、参赛人员基本信息 .................................................... - 1 - 二、创新构思与设计 ........................................................ - 1 - 1、设计目的.................................................................. - 1 - 2、创新构思.................................................................. - 2 - 三、设计方案 .................................................................... - 3 - 四、工作原理 .................................................................... - 4 - 1、机构原理说明.......................................................... - 4 - （1）旋转台的旋转机构 ......................................... - 4 - （2）齿轮传动组合机构 ......................................... - 4 - （3）传动及动力转向机构 ..................................... - 5 - （4）机械式开关机构 ............................................. - 5 - 2、控制原理示意图...................................................... - 6 - 五、样机主要零件设计图 ................................................ - 7 - 六、主要功能指标与应用前景......................................... - 9 - 1、功能指标.................................................................. - 9 - 2、应用前景.................................................................. - 9 - 七、实物照片 .................................................................. - 10 -
cad三维立体图自动生成二维三视图插件(DEFUN c:sa() (setq dcl_id (load_dialog "sanshi")) (new_dialog "sanshi" dcl_id) (action_tile "sansh_cf1" "(done_dialog 1)") (action_tile "sansh_cf2" "(done_dialog 2)") (action_tile "sansh_cf3" "(done_dialog 3)") (action_tile "sansh_cf4" "(done_dialog 4)") (action_tile "sansh_zds" "(done_dialog 5)") (setq sansh_done_id (start_dialog)) (if (> sansh_done_id 0) (progn (cond ((= 1 sansh_done_id) (sanshm_cf1) ) ((= 2 sansh_done_id) (sanshm_cf2) ) ((= 3 sansh_done_id) (sanshm_cf3) ) ((= 4 sansh_done_id) (sanshm_cf4) ) ((= 5 sansh_done_id)
(sanshm_zds) ) ) ) ) (princ) ) ;; ;;;-------------------------------------------------------- ;;;函数: CF1 ;;;-------------------------------------------------------- ;;;编制日期:2009.03.27 ;;;修改日期:2011.07.28 ;;;编制者 :曾敏辉 ;;;说明:本函数将复制并旋转对象为右视 ;;;-------------------------------------------------------- (DEFUN sanshm_CF1( / en entgrp oldort pt1 pt2 ss) (PRINC "\n 复制并旋转对象为右视") (setvar "cmdecho" 0) (setq oldort (getvar "orthomode")) (princ "\n 请选择主视图对象:") (SETQ ENTGRP (SSGET))
三维立体图转换成二维图 1.三维实体画好以后，可以观赏，也可以截成图片，固然漂亮、直观，但很多信息传递不到。因此，只有把 三维实体转成三视图，才是最实用的，可以反映三维实体的各个部位的详细信息。而怎样才能将所画好的三维实体用三视图的形式表达出来，是很多绘图者比较头疼的事情。在平面里参照三维实体一步步地画，固然可以画出，但既费时又费力，且往往容易遗漏很多信息。那么，能否在AutoCAD 中将三维实体直接转换成三视图呢？答案是肯定的。 2.下面我就详细介绍这样的操作——三维实体转三视图。 3.在转换的过程中，要用到2 个命令……“设置视图(solview)”、“设置图形(soldraw)”，这2 个命令在 CAD的各个版本中都有，是通用的。在AutoCAD2007 版及以后的版本中，还可以用“平面摄影 (flatshot)” 来制作三视图，我也刚接触，在研究后，再告知大家。 4.下面是“三维实体转三视图”的详细图解：本例为AutoCAD 实例教程，今天我们将学习通过运用AutoCAD 的“平面摄影(flatshot)”命令将三维模型转为三视图的方法，本实例适用于AutoCAD 2007 以上版本，希望能给朋友们带来帮助。 5.在AutoCAD2007 版及以后的各个版本中，还可以用“平面摄影(flatshot)”命令来进行三维实体到三视图 转换，这个转换过程是在“模型”里转换，这就给很多的后续操作带来了方便，如绘制“剖视图”、“截面图”、“转向图”等等。经过本人(shaonx)一段时间的研究试验，总结了一套转换的方法，自我感觉基本上还是成功的，因此特意做了本教程，以飨广大的网友。 6.希望本教程会给大家带来方便。下面，就是用“平面摄影(flatshot)”命令来进行从三维实体到三视图转 换的一种、也是最基础的方法，我使用CAD2008 进行操作的： 7.打开CAD，大家看到如下图的界面工具条的放置有点怪，这是为了使绘图的窗口界面最大化，便于大家看 的清楚。最上面的“建模”工具条，到后面还要换成“标准”工具条。最下面的命令行，就省略了。先画好三维实体或者打开已经画好的三维实体，可以是线框图、或消隐图、也可以是着色图(2007 版以上中的“真实”或“概念”)，我这里为了讲解的清楚，使用了“概念”。在三维实体上，我们先要有一个空间概念，即三维实体在转成三视图后的“俯视”、“前视”和“左视”的方向， 8.按照刚才的三个视图的定位，以前视图的方向为基准，用“复制”命令，将三维实体往左边复制一个，注意， 要打开“正交(也可以按F8)”，复制的这个，在以后转成的三视图里，作为“俯视图”。以一起复制。注意，还是要打开“正交(也可以按F8)”，复制后的这2 个，在以后转成的三视图里，将作为“前视图”和“左视图”。
CAD怎么将三维立体图转换为三视图 1,你已画好了立体图（立体图必须是实体的），把立体图调到你想要的那个视图（前视，俯视，左视及三维等轴测都可以） 2，点布局1（也就是进去步局），布局的视图保特和模型的视图一样（也就是说模型里是前视，布局里也是前视） 3，命令菜单栏点绘图>建模>设置>轮廓(注CAD以前的版本“建模”为“实体”），点了命令后在步局里选中立体图然后连续按4次空格键（在按空格键时你也可以仔细看看命令栏的提示） 4，点模型（就是回到模型面板），这个时候立体图就多了一层线条图了，同时图层里面多了两个以PH-BB PV－1BB命名的图层，然后你把这两个图层以外的全部图层锁定（也就是说只打开这两个图层，其它图层全都锁定） 5,如果视图是平面视图（比如前视，俯视，左视）的话你就直接“复制ctrl+c”复制整个立体图,然后新建“ctrl+n”一个图形样板，在这个新建的图形样板里“粘贴ctrl+v” 6，如果视图是轴测图那么你就要调ucs坐标了，键入命令ucs空格后输v空格视图就变成了平面视图，然后再“复制ctrl+c”到另一个图形样板里“粘贴ctrl+v” 7，在新建的图形样板里粘贴后，你会发现粘贴的图那些理论上看不到的线条也存在，你只需选中他删除就行了（因为复制过来的两个图层一个是立体图可见线，另一个是立体图理论上不可见的线条）,而后的图形是一个整体，如果想自己编辑的话，只要把这个图炸闪就行 8，一次只能一个视图，N个视图的话你就要循环这几个步骤N次，其实都很简单 proe三维图如何转化为二维图，用CAD打开 我会用CAD，会用PROE画三维图，但从来没有在二者之间相互转化过。 现在三维图已经画好，如何转成二维的？说一下大概步骤就行，谢谢 要用到工程图，新建绘图类型，把你的三维模型添加进去，转化成三视图，然后保存副本，格式为dwg 然后用cad打开它就可以了 再次求CAD三维图形转化成二维图形的过程具体的步骤说一下！！跪求了！！ 问题补充: CAD 图形啊！！！！实体图形随便一个立体图转化成二维的就是CAD软件自己可以转化的，我忘记怎末转化了。身边也没书！！！QQ 指导更好76837356！！