Tài liệu AIRBUS UKCATIA V5 and Foundation Course Sketcher docx

Standard Select - Select by clicking on an element or by clicking and dragging a rectangle around the elements you wish to select, when the mouse button is released all the elements full

Compiled by: Kevin Burke Approved by: Authorised by:

Foundation Course

Sketcher

Session 3 – The Sketcher Workbench 3

An Introduction to Sketcher 4

Renaming a Node name on the Specification Tree 5

Accessing the Sketcher Workbench 6

Selecting a Sketch Plane 7

The Sketcher Workbench 8

Sketcher Toolbars and Icons 10

Selecting and Positioning Geometry 12

The Profile Toolbar 14

The Profile Icon 14

Pre-Defined Profiles 18

Circles and Arcs 22

2D Splines 24

Conical Shapes 25

Lines 26

Axis Line 29

Points 29

Editing the Definition of an Element 32

The Operations Toolbar 33

Create 2D Fillets 33

Relimitation or Trim functions 36

Transformation Tools 39

3D Geometry 45

Cutting the Part by Sketch plane 49

Constraints 50

Constraint and Element Colours 51

The Constraints Toolbar 53

Create Constraints using a dialog box 53

Create Constraints by selecting elements 54

Create Automatic Constraints 56

Animates Constraints 58

Managing Constraints 58

Linking Constraints Together 60

Further Sketcher Options 63

An alternative way of entering Sketcher 63

Editing a Sketch 64

Changing the Sketch Support 64

Sketch Analysis Tool 65

Session 3 – The Sketcher Workbench

On completion of this session the trainee will:

♦ Be able to access the Sketcher Workbench

♦ Understand the Sketcher Toolbars and Icons

♦ Be able create and manipulate 2D Geometry

♦ Be able to apply and manipulate Constraints

wireframe geometry To position and control the size of the sketch, geometric andpositional constraints are used which are displayed in green A Sketch Node will be

attached to the Specification Tree in which the Sketch Axis, Geometry and

Constraints details are held The Specification Tree can be expanded by selecting the

‘+’ symbol on the Tree Branch or collapsed by selecting the ‘-‘ symbol.

GeometricConstraints

SpecificationTree

Wireframe

Geometry

Renaming a Node name on the Specification Tree

You can edit the name of a node on the Specification tree by selecting it with MB1 followed by MB3 to display a contextual menu Now select Properties to display a Properties panel for the selected

In the Feature Name field on the

Feature Properties tab is the name of

the Node Select this field and enter the

new name for the Node and click OK to

apply the change

Node name to

be edited

Accessing the Sketcher Workbench

To access the Sketcher

workbench select > Start > Mechanical Design > Sketcher

from the Start drop down menu

or select the Sketcher Iconfrom any workbench thatallows sketches to becreated

If a CATPart is not active a new part will be activated and you will be prompted to

enter a part name by following panel on the desktop Enter a name and click on OK

and a new CATPart will open

Note: If the part is to be stored on the vault the name must be in uppercase and conform to the relevant project naming convention.

Selecting a Sketch Plane

The sketcher icon will now be orange and you will be prompted to select a plane, a

planar face or a sketch this is known as the Sketch Support Select the required

plane, face or sketch and the catia desktop will switch to the sketcher workench andgraphic display

Select a Plane fromthe SpecificationTree or Graphically

For additionalinformation oncreating user definedPlanes see the PartDesign Session

Select a Planar face

on an existing solid

Select an existing

The Sketcher Workbench

and a origin point

This is the Sketch

Absolute Axis and

Geometry

Part Specification

Tree

SketcherWorkbenchToolbarsSketch Grid

SketchToolsToolbaSketch Axis

H Axis

The graphic display area will have a Grid displayed on the sketch plane to which

geometry can be snapped It is possible to change sketcher interface features such as

the grid size by selecting Tools>Options from the Tools drop down menu followed

by the Mechanical Design>Sketcher branch on the displayed panel.

The Grid section controls the visibility, size and whether grid snapping is used The Sketch Plane section allows the sketch plane to be shaded and to automatically

position the sketch plane parallel to the screen

The Geometry section allows the creation of circle/ellipse centre points and the

manipulation of geometry by the use of the mouse

The Constraints section switches on automatic constraints where appropriate.

The Colors section controls element colours.

SketcherWorkbench Icon

Profile Creation

Constraints

Selection IconExit Sketcher

Sketcher Toolbars and Icons

There are four main toolbars within thesketcher workbench: -

1 Profile Creation – used for the

creation of geometric elements

2 Operations – for dressing-up

(Filleting, Trimming, etc.) andmanipulating geometry (Mirroring,Translating, etc.)

3 Constraints – for controlling

geometry size and position

4 The Sketch Tools toolbar – is used

for positioning and controllinggeometry and is described on thefollowing page

The above commands are also

accessible via the Insert drop down

menu

Sketch Tools – for controlling grid snapping, construction geometry and applying

automatic constraints

When automatic geometric constraints are enabled geometric controls are applied to

the element being created, automatic dimension constraints are only created on fillet

radii and chamfers or when entered in the relevant field on the Sketch tools toolbar

All the constraints will appear in the specification tree under the Sketch node

Unwanted constraints can be deleted by selecting the constraint with the left mouse

button followed by the Delete key or use the right mouse button and select delete

from the context menu A more in depth explanation of constraints is given further on

in this session

Geometric Constraint

Grid snapping toggle

(orange indicates grid

snapping is on)

Automatic Geometricconstraints (orangeindicates geometricconstraints will be created)

Construction geometry

toggle (orange indicates

construction geometry will

be created)

Automatic Dimensionalconstraints (orange indicatesdimensional constraints will

be created)

Fields for entering constraintvalue manually

Selecting and Positioning Geometry

Individual geometry can be selected by either graphically or from the specificationtree using the left mouse button Two or more elements can be selected by pressing

the Ctrl Key in conjunction with the left mouse button Finally selection can be

performed by using one of the selection icons and the left mouse button

Standard Select - Select by clicking on an element or by clicking and

dragging a rectangle around the elements you wish to select, when the mouse button

is released all the elements fully contained within the rectangle are selected

Selection Trap - Similar to the standard select command except individual

element cannot be selected Select by clicking and dragging a rectangle around theelements you wish to select, when the mouse button is released only the elementsfully contained within the rectangle are selected

Intersecting Trap - Select by clicking and dragging a rectangle around the

elements you wish to select All elements contained within and crossing the rectangleare selected

Polygon Trap – Select by

enclosing the required elements

Select

SelectionTrap

IntersectingTrap

PolygonTrap

PaintStrokeSelection

Paint Stroke Selection – Select by clicking and dragging a curve through the

elements that you wish to select When you double click the mouse button all

elements that are crossed by the curve are selected

In all cases the selected geometry will turn orange

Once you selected the geometry it can be repositioned by click and dragging the leftmouse button to the desired position Remember that all elements that are linked orconstrained to the moving elements will also be affected

To deselect the all the elements click anywhere on the graphics window with the leftmouse button

The Profile Toolbar

Used to create wireframe geometry with sketcher

Note: By using automatic geometric constraints when creating elements the shape will

be maintained if an element within the profile is moved The profiles can be definedeither by selecting graphic locations, entering the values via the sketch tools toolbar or

by snapping to existing geometry in the current sketch

The Profile Icon

Creates a profile consisting of lines and arcs On selecting this icon the sketchtools toolbar changes to display further options and you are prompt to enter the startpoint of the profile By default the first element will be a Line as indicated by the

icon being highlighted in the toolbar, although you can start with an Arc

With the automatic dimensions constraint icon selected it is possible to create a

profile two ways

1 You can enter the ordinates of the start and end points of the line in the ordinate

fields followed by the Enter Key for each point, this will display both the start

and end points plus the constraint values on the screen

2 You can click on the sketch plane to indicate the start and end points but no

constraints will be generated, although they can be added at any time This is the

Creates a profile consisting of lines and arcs

Creates circles and arcs

Having created the start point you have to enter an end point using either method, forthis example will use the mouse clicks to define the profile Click on the sketch plane

to indicate the end point of the line The length and angle of the line is displayed onthe sketch tools toolbar In some case the element will be displayed in blue before youclick, this indicates a constraint can be automatically generated if the automatic

geometric constraint icon is selected In this case a horizontal constraint is created

To create a tangent arc you can either:

-1 Select the Tangent Arc icon and click to indicate the end of the arc

2 Click and dragging the mouse pointer in the direction you wish the arc to appear,then release the button and the sketch tool will switch to insert tangent arc mode.Now click to indicate the end of the arc Again the arc will turn blue if automaticgeometric constraints are available

The size of the radius is dynamically displayed on the sketch tools toolbar again youcould enter the size directly into this field

Line lengthand Angle

Tangent

Value

The sketch tools toolbar switches back to insert line mode once the arc is completed.Indicate the end point for the line using the left mouse button, again the line length isdisplayed on the toolbar.

Finally click and drag from the end of the line to switch to insert arc mode, then selectthe start of the first line to close the profile As you hover over the start point of theline a blue circle with a solid blue dot will appear, which indicates the end of the arcwill snap to the start of the line if you click Once the profile is closed the command iscompleted If an open profile is required you can either double click after completing

an element or deselect the profile icon to terminate the command If a mistake is madewhen defining a profile, you can click on the Undo icon during the command tostep back through the profile

Element snappingindicator

Starting a Profile with a three point Arc.

To start the profile with a arc rather than a line the following method can be used

1 Select the Profile icon then click to indicate start point of the arc followed by theinsert three point arc icon on the sketch tools toolbar

2 Click to indicate the second point

3 Finally click to indicate the end point of the arc

The profile command will now switch back to insert line mode

Note: Complete circles can not be produced using this icon

Arc startpointInsert 3

Point Arc

Pre-Defined Profiles

Creates pre-defined profiles

Creates a rectangle using 2 points or locations

Click to indicate the first corner of the rectangle followed by second click to indicatethe diagonally opposite corner

Insert a

Rectangle Insert a

Parallelogram

Insert anOrientedRectangle

Insert aKeyholeProfile

Insert anElongated Hole

Insert aHexagon

Insert aCylindricalElongated Hole

Secondpoint

First

point

Size ofrectangleOrdinate values

of the points

Creates an Orientated Rectangle using 3 points or locations.

Click to indicate the first corner of the rectangle followed a second click to completethe first side Finally click a location to indicate the diagonally opposite corner

Creates a Parrallelogram using 3 points or locations

Click to indicate the first corner of the Parrallelogram followed by the second click tocomplete the first side Finally click a location to indicate the diagonally oppositecorner

First

point

ThirdpointSecond

point

Creates an Elongated Hole or Slot using 3 points or locations.

The first two points selected using the mouse will define the position and length of the

slot axis The third selection controls the size of the slot

Creates a Cylindrical Elongated Hole or Slot

The first selection indicates the centre point of the radial axis of the slot The second

and third selections define the radius and radial length of the slot The final selection

defines the size of the slot

Thirdpoint

SlotAxis

SecondpointFirst

point

First point(Centre of slot axis)

Thirdpoint

Second

Fourthpoint

Creates a Keyhole profile using 4 points or locations.

The first selection indicates the centre of the large radius of the profile The secondindicates the centre of the small radius, the third selection defines the size of the smallradius and finally the last selection indicates the size of the large radius

Creates a Hexagon profile using 2 points or locations

The first selection indicates the centre of the Hexagon and the second define the size

of the profile

Firstpoint

Secondpoint

Firstpoint

Thirdpoint

Secondpoint

Fourthpoint

Circles and Arcs

Creates Circles and arcs

Creates a Circle using 2 points or locations

The first selection indicates the centre of the circle and second defines its size

Creates a Circle through 3 points or locations

Creates a Circle using Cartesian or Polar ordinates

After selecting the icon a Circle Definition panel will appear Select either the

Cartesian or Polar Tab and enter the Center Point ordinates as required Enter the radius size in the Radius field and click the OK button to insert the circle The circle

is generated with the controlling constraints The Center Point constraints are relative

to the sketch axis H and V.

Insert a Tri-TangentCircle

InsertArc

Insert a 3Point circle

Insert

Circle byordinates

Insert a 3 PointCircle with limits

Insert a

3 PointArc

Constraints

Creates a Circle tangent between 3 elements.

After selecting the icon select the 3 elements you wish the Circle to be tangent to

Creates an Arc through 3 points or locations

Select 3 locations to create the Arc (Start point, Mid point and then End point) Thearc can be changed to a full circle or compliment arc by using use the right mousebutton to access the contextual menu whilst the arc is highlighted in orange, you can

then select the Circle object tab to access the Close and Complement options.

Circle tangent

to 3 Lines

Circle tangent

to a Line, Splineand a PointCircle tangent

to 3 Circles

Creates an Arc using 3 points or locations starting with its limits.

Select 3 locations (Start point, End point and then Mid point) Again the contextualmenu can be used to close to a circle or create a complement arc

Creates an Arc using 3 points or locations

The first selection indicates the centre point of the arc, the second defines the radiusand its start point The final selection defines the end of the arc

2D Splines

Creates 2D Splines and Connect Curves

Creates a 2D Spline through a series of Control points or locations

Select a series of locations known as Control Points through which a 2D Spline isgenerated as you define the control point locations Double click the finish the Spline

Insert 2DSpline

Insert aConnect Curve

Spline

ControlPoints

Conical Shapes

Creates Conical shaped elements

Creates an Ellipse using 3 points or locations

Firstly select a location to indicate the centre of the ellipse followed by a location todefine the Major axis radius and finally a location to define the Minor axis radius.Remember the sketch tools toolbar displays the geometric values of the ellipse as it isbeing define

Creates a Parabola defined by its Focus point using 4 points or locations

The first selection defines the Focus point, the second defines the Apex, the third andfourth define the start and end points of the Parabola

Creates a Hyperbola defined by its Focus point using 5 points or locations.First select the Focus point, followed by the centre intersect point The third selectiondefines the Apex, the fourth and fifth define the start and end points of the Hyperbola

Insert aParabola

InsertHyperbola

Insert aConic

Insert anEllipse

First

point

Secondpoint

Thirdpoint

Creates a Conic using 5 points or locations.

The first and second selection indicates the start and end points of the conic, the thirddefines the Apex, the fourth and fifth defines the shape of the conic

Lines

Creates Line type elements

Create Lines using 2 points or locations

There are two methods of creating a lines

1 Create a line by defining its start and end points(default option) The first selection

Firstpoint

Third(Apex)point

Fourthpoint

Secondpoint

Fifthpoint

Insert aLine

Insert a Bi-Tangent

Line

Insert anInfinite Line

Insert aBisectingLine

2 Create a line symetrically about a mid point To create a line in this way select the

Insert Line icon followed by the Symmetrical Extension icon on the sketch tools

toolbar The first selection indicates the mid point of the line followed by a secondwhich defines one end of the line and generates the other end symetrically aboutthe mid point

Note: If automatic contraints are selected a symmetrical constraint is applied to the line to ensure that in the event that the length of the line is changed the

Infinate Line icon select Line Through Two Points icon on the sketch tools toolbar

and select two locations to generate the line

Horizontal

Line

Line ThroughTwo Points

Vertical

Creates a Line tangent between to elements.

After selecting the icon select the two elements that between which you want to createthe line between

Note: The line attempts to attach to the element at the point you select Again use automatic geometric constraints are selected to maintain tangency when the elements are moved or resized.

Creates an Infinite Bisecting Line between two existing lines.

Select the icon followed by the two existing lines

A Tangent Line

between two

Circles

A Tangent Linebetween twoSplines

InfiniteBisectingLine

Existing

Lines

Axis Line

The Axis Line is used to create revolved Solids and Groove features

To create an Axis line select the icon and followed by to points or locations to definethe length and position of the line

Note: Only one Axis line is allowed per sketch and it can not be a construction element.

Points

Creates Point type elements

Creates a Point by selecting locations

Creates a Point using Co-ordinates

After selecting this icon a Point Definition panel

will appear and either use the Cartesian or Polar

tab to enter the position of the point relative to the

Insert aProjectedPoint

Insert aIntersectionPoint

Insert Point

spaced Points

Insert Point byco-ordinatesAxis Line

Profile

Creates equally spaced multiple points along a line or curve.

Select the icon followed by the line curve on which you require the points An

Equidistant Point Definition panel will appear Enter the number of point required

in the New Points field Reverse direction can only be used on a line and will result

in the points appearing off the line at one end

Note: If the automatic geometric constraint icon is not selected during point creation the resulting points will not be associated to the line or curve.

If automatic dimensional constraints are selected the resulting points will have constraint applied to them that control the spacing, unfortunately they do not updated when the original line or curve is changed in length.

Number of point(excluding end points)

Preview of pointpositions

Resulting Points on a line

Creates a point at intersection of two elements.

After selecting the icon select the two elements to intersect

Note: You can only intersect two elements To maintain associativity between the two elements and the intersection points Geometric constraints can be used but they are applied by selecting the Dimensional constraints icon and not the

Geometric constraints icon.

Creates a point by projecting existing point onto an element

Select the icon and then proceed to select the points that you wish to project Finallyselect the element on which the points are to be projected Again use the automaticdimensional icon to apply geometric constraints to maintain associativity between thepoints and the element

Editing the Definition of an Element

The majority of the elements and features created in workbenches can be edited oncethey have been created To perform this task either double click on the element that is

to be edited or select it using the left mouse button followed by the MB3 to access the contextual menu Select the XXXX.Object from the menu followed by Definition to

access the Definition panel for the element