ىلولاا ةلحرملا · ameer mosa thoeny. 2 1-polygon: the polygon command enables you to...
TRANSCRIPT
1
Department of Computer Engineering& Information Technology
قسم هندسه الحاسبات و تكنلوجيا المعلومات
المرحلة االولى
Lecture (13)
Polygon, Polyline and donut
Issued by Assistant Lecturer
Ameer Mosa Thoeny
2
1-POLYGON:
The POLYGON command enables you to draw multi-sided,
closed figures with equal side lengths. You can draw polygons that
have from 3 to 1,024 sides. To draw a polygon, choose Polygon from
the Draw toolbar.
First specify the number of sides. Then choose one of three methods
of defining the polygon.
There are three ways to draw polygon
1. Edge option: Choose the Edge option. Specify the two endpoints of any edge of
the polygon to complete the polygon.
The command syntax for copy is as follows:
Command: polygon
Enter number of sides <5>: 5
Specify center of polygon or [Edge]: e
Specify first endpoint of edge: 10,10
Specify second endpoint of edge: 20,20
2. Inscribed in circle: After specifying the center, choose Inscribed in Circle. Then
specify the radius from the center to a vertex (point). This defines the
polygon with reference to an imaginary circle whose circumference
touches all the vertices of the polygon.
3
The command syntax for copy is as follows:
Command: polygon
Enter number of sides <4>: 5
Specify center of polygon or [Edge]: 20,20
Enter an option [Inscribed in circle/Circumscribed about circle] <I>:I
Specify radius of circle: 10
3. Circumscribed about circle:
After specifying the center, choose Circumscribed about Circle.
Then specify the radius from the center to the midpoint of a side. This
defines the polygon with reference to an imaginary circle whose
circumference touches all the midpoints of the polygon’s sides.
The command syntax for copy is as follows:
Command: polygon
Enter number of sides <5>: 5
Specify center of polygon or [Edge]: 20,20
Enter an option [Inscribed in circle/Circumscribed about circle] <I>: c
Specify radius of circle: 10
4
2-PLOLYLINE:
The command syntax for copy is as follows: Command: pline
Specify start point: 0,0
Current line-width is 2.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: w
Specify starting width <2.0000>: 2
Specify ending width <2.0000>: 2
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: 20,20
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 40,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 60,20
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 80,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 100,20
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:enter
Command: pline
Specify start point: 0,0
Current line-width is 0.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: w
Specify starting width <4.0000>: 2
Specify ending width <2.0000>: 10
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: 60,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 120,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:
5
Command: pline
Specify start point: 0,0
Current line-width is 10.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: w
Specify starting width <10.0000>: 2
Specify ending width <2.0000>: 10
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: 60,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: w
Specify starting width <10.0000>: 2
Specify ending width <2.0000>: 10
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: 120,0
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:
3-Making Donuts A donut is a wide polyline that looks like two concentric circles. You
define a diameter for the inner and outer circles.
Donuts are often used in electrical drawings to create symbols. If the inner
circle’s radius is zero, you create a filled-in circle.
6
The real view of donut as below:
The command syntax for copy is as follows:
Command: donut
Specify inside diameter of donut <1.0000>: 20
Specify outside diameter of donut <5.0000>: 80
Specify center of donut or <exit>: 10,10
Specify center of donut or <exit>:
7
Department of Computer Engineering& Information Technology
قسم هندسه الحاسبات و تكنلوجيا المعلومات
المرحلة االولى
Lecture (14) Create Region and
Boolean command: Union Subtract Intersect
Issued by Assistant Lecturer
Ameer Mosa Thoeny
8
1) REGION: Regions are two-dimensional surfaces.
The region command converts one object or a set of objects forming
a closed shape into one object called a Region.
This similar to the way in which a set of objects (lines, arcs, plines, etc.)
forming a closed shape and having matching and points can be converted
into a closed pline.
A region, however, has special properties:
1. Several regions can be combined with Boolean operations known as
union, subtract, and intersect to form a ―composite‖ region.
2. A region is considered a planer surface. Region can be used with
surface modeling.
The appearance of the object does not change after the conversion,
even though the resulting shape is one object.
Although the region appears to be no different than a closed pline, it is
more powerful because several regions can be combined to form complex
shapes (composite regions) using the three Boolean operations.
And our drawing can calculate more information from regions than from
polylines, such as the centroid, moments of inertia, and other properties
relating to mass. You can also create complex shapes by combining,
subtracting, and intersecting regions.
Although these commands are most often used for 3D drawing, they’re often
used in 2D drawing as a preparation for 3D drawing.
Consider the shape below composed of four connecting lines, using region
combines the shape into one object, a region.
To create a region, choose Region from the Draw toolbar. The prompt
asks you to select objects. Select all of the objects and press Enter to end
object selection.
9
Our can be creating using region command as shown below:
Command: region
Select objects: pick L1
Select objects: pick L2
Select objects: pick L3
Select objects: pick L4
Select objects: enter
1 region created.
2) Boolean commands: The Boolean operators, union, subtract, intersect, can be used within
regions as well as solids. Any number of these commands can be used with
regions to form complex geometry.
The first step is to convert the lines and circle to region, then union, subtract,
intersect can be used.
a. Union: Union combines two or more regions (or solids) into one region or
(solids). Invoking union causes AutoCAD to prompt you to select objects.
You can only existing regions (or solids).
We can use it as shown below:
Command: union
Select objects: pick (region)
Select objects: pick (region)
Select objects: enter
The selected regions are combined into one composite region.
Before union
After union
10
b. Subtract: Subtract enables you to remove on region (or set of regions) from
another. The regions must be created before using subtract (or another
Boolean operator). Subtract also works with solids (as do the other Boolean
operations).
There are two steps to subtract:
1) Select the region or set of regions to ―subtract from‖ (these that you
with to keep).
2) Select the region ―to subtract‖ (these you want to remove).
We can use it as shown below:
Command: subtract
Select objects: pick
Select objects: enter
Select regions to subtract
Select objects: pick
Select objects: enter
Before union
After union
11
c. Intersect: Intersect is the Boolean operator that finds the common area from
two or more regions.
We can use it as shown below:
Command: intersect
Select objects: pick
Select objects: pick
Select objects: enter
Before union
After union
12
Exercise:
Create the drawing below using (rectangular and circle) drawing command
Then use region and Boolean command to modify it?
13
Department of Computer Engineering& Information Technology
قسم هندسه الحاسبات و تكنلوجيا المعلومات
المرحلة االولى
Lecture (15) Dimensions
Linear, Aligned, diameter, radius, Angular and
Style Manager
Issued by Assistant Lecturer
Ameer Mosa Thoeny
14
Working with Dimensions: Dimensioning is usually done after you complete all or most of a drawing.
When you dimension a drawing all at once, you can create a unified,
organized look for your dimensions.
The elements of a dimension: A dimension is a complex object, containing many parts. Understanding
these parts and how they relate to the object you’re dimensioning is an
important first step. Figure below shows a typical linear dimension.
✦Extension lines: These extend from the dimensioned object to the
dimension line and arrowheads.
✦Dimension text: This tells you the actual measurement of the
dimensioned object. You can format this text in decimals, fractions,
scientific units, and so on.
✦Dimension line: This extends between the extension lines.
✦ Arrowheads: These mark the intersection of the dimension line and the
extension lines. They can take several forms, such as tick marks, open
arrows, or dots.
15
1) Linear Dimensions Just as the most common objects are lines, the most common
dimensions are linear dimensions. Use linear dimensions for lines, a straight
segment of a polyline, or a straight segment in a block. You can also use a
linear dimension for arcs and circles — you get the linear length of the arc
(not its perimeter length) and the diameter of the circle.
Specifying the linear dimensioned object To dimension a line, choose Linear Dimension from the Dimension toolbar
or from standard bar- dimensions – linear.
Command: dimlinear
Specify first extension line origin or <select object>: pick
Specify second extension line origin: pick
Specify dimension line location or [Mtext/Text/Angle/Horizontal/Vertical/Rotated]: pick
Dimension text = 24.7411
2) Aligned Dimensions
When you want to dimension a linear object that is not orthogonal, use an
aligned dimension. The dimension lines of an aligned dimension are always
parallel to the object, unlike rotated dimensions. An aligned dimension
measures the actual length of the object, not a vertical or horizontal distance
that you dimension with a linear dimension.
16
Specifying the Aligned dimensioned object To dimension a non orthogonal line, choose Aligned Dimension from the
Dimension toolbar or from standard bar- dimensions – Aligned.
Command: dimaligned
Specify first extension line origin or <select object>: pick
Specify second extension line origin: pick
Specify dimension line location or[Mtext/Text/Angle]: pick
Dimension text = 21
Dimensioning Arcs and Circles 3) diameter dimensions When you want to dimension of an arc or circle objects, use an diameter
dimension.
Specifying the circle diameter dimension To dimension a circle diameter, choose diameter Dimension from the
Dimension toolbar or from standard bar- dimensions – diameter.
Command: dimdiameter
Select arc or circle: pick
Dimension text = 8
17
4) Radius dimensions
When you want to dimension of an arc or circle objects, use a radius
dimension.
Specifying the circle radius dimension To dimension a circle radius, choose radius Dimension from the
Dimension toolbar or from standard bar- dimensions – radius.
Command: dimradius
Select arc or circle: pick
Dimension text = 4
5) Marking arc and circle centers Circle and arc centers are often marked in mechanical drawings because the
center is an important aspect of a circle or arc but is not obvious without a
mark. You set the size and type of mark when you create a dimension style.
Specifying the Center Mark dimensioned object To dimension a center mark, choose center Mark Dimension from the
Dimension toolbar or from standard bar- dimensions – center Mark.
Command: dimcenter
Select arc or circle: pick
18
6) Angular dimensions
When you want to dimension of an arc or angle objects, use an angular
dimension.
Specifying the Angular dimension To dimension a angel or arc, choose angular Dimension from the
Dimension toolbar or from standard bar- dimensions – angular.
Command: dimangular
Select arc, circle, line, or <specify vertex>: pick
Specify dimension arc line location or [Mtext/Text/Angle]: pick
Dimension text = 136
19
Understanding Dimension Styles
You should create your dimension styles before dimensioning. In
general, you create a dimension style, save it in your template drawings, and
(you hope) rarely have to deal with it again.
To create a dimension style, choose Dimension Style from the Dimension
toolbar to open the Dimension Style Manager, or from standard bar-
dimensions – style.
To create a new style, click New to open the Create New Dimension Style
dialog box.
20
Then specify the wanted parameters as below:
The New Dimension Style dialog box has the following tabs:
✦ Lines: Sets specifications for dimension lines and extension lines.
✦ Symbols and Arrows: Sets specifications for arrowheads, center marks,
the arc length symbol and the jog angle for dimensioning large radii.
✦ Text: Determines the appearance, placement, and alignment of
dimension text.
✦ Fit: Sets how text and arrows fit inside narrow dimensions, as well as
where text is placed when it doesn’t fit in its default position. This tab also
allows you to set the scale factor for dimension features, and whether to
place a dimension line inside narrow dimensions.
✦ Primary Units: Determines the format and precision for the primary
measuring unit for both linear and angular dimensions.
✦ Alternate Units: Determines the format and precision for secondary
units, if turned on (such as metric measurements if your primary units are
English, or vice versa).
✦ Tolerances: Formats tolerances.
21
NOTE:
a. Changing line type done from properties bar.
b. Change precision then, right click on dimension –precision -0
As shown below:
22
Department of Computer Engineering& Information Technology
قسم هندسه الحاسبات و تكنلوجيا المعلومات
المرحلة االولى
Lecture (16) Rotate and Explode
Issued by Assistant Lecturer
Ameer Mosa Thoeny
23
1. Rotating objects:
You can easily rotate an object or objects around a base point that you
specify. The base point is usually an object snap point on the object. To
indicate the rotation, specify an angle of rotation.
As explained before, zero degrees is generally to the right, and
degrees increase counterclockwise, although you can change this convention.
How to rotate object: 1. To rotate an object, choose Rotate from the Modify toolbar and select
an object. Alternatively, select an object and then choose Rotate from
the Modify toolbar.
2. By the prompt using command: Rotate
Methods use Rotate command: There are two ways to run rotate command as shown below:
1. Using normal rotate from 0 angles on right side and counterclockwise:
Command: rotate
Current positive angle in UCS: ANGDIR=counterclockwise ANGBASE=0
Select objects: pick
Select objects: enter
Specify base point: pick
Specify rotation angle or [Reference]: 90
Before rotate After rotate
24
2. Using reference option to determine new 0 angle according specify angle or two point:
Command: rotate
Current positive angle in UCS: ANGDIR=counterclockwise ANGBASE=0
Select objects: pick
Select objects: enter
Specify base point: pick
Specify rotation angle or [Reference]: r
Specify the reference angle <0>: Specify second point:
Specify the new angle: 90
Before rotate After rotate
2. Explode command: You can explode object into their original objects. You may
need to do this to edit it.
How to explode object: 1. To rotate an object, choose explode from the Modify toolbar and
select an object. Alternatively, select an object and then choose Rotate
from the Modify toolbar.
2. By the prompt using command: explode
Methods use explodes command: There are two ways to run rotate command as shown below:
Command: explode
Select objects: pick
25
Exercise1: use polygon command, explode and rotate to drawing the
following shape, where the circle radius of outer polygon is 10unit
and the circle radius of inner polygon is 4.5unit:
Exercise2: draw the following shape using suitable command: