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1、Sketcher Preface Whats New ? Getting Started Basic Tasks Customizing Workbench Description Glossary Index Dassault Systmes 1994-99. All rights reserved. Preface CATIA Version 5 Sketcher application makes it possible for designers to sketch precise and rapid 2D profiles. Using This Book This book is
2、intended for the user who needs to become quickly familiar with CATIA Sketcher Version 5 product. The user should be familiar with basic CATIA Version 5 concepts such as document windows, standard and view toolbars. To get the most out of this guide, we suggest you start reading and performing the s
3、tep-by-step tutorial Getting Started. This tutorial will show you how to create a basic profile using autodetection. The next sections deal with various types of profiles and associated operations as well as more details on constraints that can be applied to these profiles. You may also want to take
4、 a look at the sections describing the Sketcher menus and toolbars at the end of the guide. Where to Find More Information Prior to reading this book, we recommend that you read the CATIA - Infrastructure Users guide Version 5. Whats New? Simple Profiles New: Creating Parabola by Focus New: Creating
5、 Hyperbola by Focus New: Creating Arcs (Three Points) Using Limits Enhanced: Points New: Creating Symmetry Lines Enhanced: Creating Axes Operations on Profiles New: Closing Elements Enhanced: Creating Symmetrical Elements New: Translating Elements New: Rotating Elements New: Offsetting Elements New:
6、 Copy/Pasting Projected/Intersected Elements New: Scaling Elements Constraints Enhanced: Using Autodetection Enhanced: Creating Constraints via a Dialog Box Enhanced: Quickly Creating Dimensional Constraints New: Defining Constraint Measure Direction Enhanced: Auto-Constraining a Group of Elements G
7、etting Started The Sketcher workbench provides a set of functionalities for creating and modifying sketched elements. Note that you can apply constraints to the elements. Tasks This tutorial should take about ten minutes to complete. Entering Sketcher Workbench This task shows how to enter the Sketc
8、her workbench. 1. Select Start - Mechanical Design - Sketcher from the menu bar. Three reference planes are available. They are displayed both in the geometry area and in the specification tree. 2. Click the desired reference plane either in the geometry area or in the specification tree. You can al
9、so enter the Sketcher workbench by: multi-selecting two edges (to define h and v - the axis is aligned on these two edges) selecting one surface (reference plane) selecting the Sketcher icon. You can also enter the Skecther workbench by double-clicking one sketch element. Note that if you select one
10、 or two edges, h will be parallel to the projection of the first edge in the sketch plane. If the two projected edges appear as two lines tha intersect in the sketch plane, the origin of the skecth axis will correspond to the two lines intersection point. The Sketcher workbench appears as follows: A
11、 grid is displayed which is optional. You can modify the grid characteristics via Tools-Options-Part. For more information, see CATIA- Infrastructure Users guide Version 5. Creating a Profile This task shows how to create a profile beneath an existing profile. You will use autodetection as a guide f
12、or creating profiles. Before starting to learn how to sketch, just remember that whatever operations you are performing in the Sketcher, the application automatically updates the geometry. 1. Click on the Profile icon . 2. Click to position the top right-hand corner of the new profile. If you move t
13、he cursor around the screen, a line to be used for autodetection follows the cursor. The current values of the profile being created are simultaneously displayed in the Tools status bar. Note that you can drive the profile to be created by entering the values in this status bar. 3. Click to position
14、 the top left-hand corner of the new profile. 4. Click the required points on the profile. 5. Click to end the profile. In this particular case, what you do is select the start point. A line is set to the red color each time this line is to be used as reference for autodetection. A line is set to th
15、e blue color eac time it is detected as an horizontal or a vertical line. 6. If needed, drag the cursor for modifying the profile location. 7. Click to position the profile. The profile newly created is assigned what we call a constraints. In other words, and as you can see above, the profile newly
16、created is assigned parallelism constraints. A green-colored parallelism symbol is assigned between both profiles. Editing a Profile Shape and Size This task shows how, when you first access the Sketcher, you can use the modification mode. Most of your sketching will involve the modification of the
17、shape and size of your sketched elements. Create two profiles with parallelism constraints. 1. Select one end side of the profile. 2. Drag on of the right end sides of the profile anywhere to the right. The parallelism constraint remains active. 3. Drag diagonally one corner of the profile. The para
18、llelism constraint remains active. You have just stretched the profile (shape and size) without having to use any intermediary menu options. You can modify the profile directly simply using the mouse. Leaving Sketcher Workbench This task shows you how to leave he Sketcher workbench. 1. Click the Exi
19、t icon . You are now in the Part Design Workbench. Basic User Tasks The Sketcher workbench provides a simple method for creating and editing two-dimensional geometry as well as creating relations between geometrical elements. Once created, you can set constraints between geometrical elements, if you
20、 need more complex sketches. Theme Before You Begin Before you begin, you should be familiar with the following. Sketcher ElementSketcher Color Current elementwhite Selected elementhighlighted (red) Protected elementyellow Fixed elementgreen Isoconstrained elementgreen Overconstrained elementviolet
21、Tasks Using Tools For Sketching This task shows how CATIA can assist you when sketching elements. The Tools toolbar is displayed in the bottom right part of the CATIA screen and provides the following options: Snap to Point options Construction/Standard Element options Internal Constraints options V
22、alue fields (Tools toolbar) The toolbar is not necessarily entirely visible. We advise you undock it for displaying all the available options and fields. Snap to Point If activated, this option makes your sketch begin or end on the points of the grid. As you are sketching the points are snapped to t
23、he intersection points of the grid. Note that this option is also available in the Tools - Options - Sketcher tab. For more information, see CATIA.Infrastructure users guide (Customization Settings). In the following example, the white spline was created with Snap to Point on. The points are on the
24、grid. Conversely, the here highlighted spline was created with the Snap to Point option deactivated. Note that when you zoom in, snapping option remains active both on primary and secondary grids, even though the secondary grids are not visualized any more. When Autodetection is active, points may n
25、ot position at the intersection points of the grid. Care that they will necessarily position on an horizontal or a vertical grid subdivision. The autodetection capability works even if this option is on. Construction/Standard Elements You can create two types of element: standard elements and constr
26、uction elements . If standard elements represent the most commonly created elements, on some occasions, you will have to create a geometry just to facilitate your design. Construction elements aim at helping you in sketching the required profile. To know more about these elements, please refer to Di
27、fferentiating Between Elements and Construction Elements. Internal Constraints If activated, the application creates the constraints specific to the elements you are sketching. In the following example, only the white oblong profile was created with this option. To know more about sketcher constrain
28、ts, please refer to Setting Constraints, and CATIA.Infrastructure users guide (Customization Settings). Value Fields (Tools Toolbar) The values of the elements you sketch appear in the Tools toolbar as you move the cursor. In other words, as you are moving the cursor, the Horizontal (H), Vertical (V
29、) Length (L) and Angle (A) fields display the coordinates corresponding to the cursor position. You can also use these fields for entering the values of your choice. In the following scenario, you are going to sketch a line by entering values in the appropriate fields. 1. Click the Line icon. The To
30、ols toolbar displays information in the four value fields. 2. Enter the coordinates of the First Point. 3. Enter the coordinates of the Second Point. OR 4. Enter the length (L) of the line. 5. Enter the value of the angle (A) between the line to be created and the horizontal axis. 6. Click the first
31、 point on the line. The line is created. Depending on the number of fields available and the way you customize your toolbars, some fields may be truncated. What you need to do is just undock the Tools toolbar. Cutting the Part by the Sketch Plane This task shows how to make some edges visible. In ot
32、her words, you are going to simplify the sketch plane view by hiding the portion of material you do not need for sketching. 1. Select the plane on which you need to sketch a new profile and enter the Sketcher workbench. Once in the Sketcher, you obtain this view, which does not show the edges genera
33、ted by the shell feature. 2. Now, click the Cut Part by Sketch Plane option to hide the portion of part you do not want to see in the Sketcher. You obtain this view without the material existing above the sketch plane. The edges corresponding to the shell are now visible. The edges resulting from th
34、e intersection are not visualized and therefore cannot be selected. 3. You can now sketch the required profile taking these edges into account. Creating Standard or Construction Elements This task shows how to create standard elements or construction elements. Note that creating standard or construc
35、tion elements is based upon the same methodology. If standard elements represent the most commonly created elements, on some occasions, you will have to create geometry just to facilitate your design. Indeed, construction elements aim at helping you in sketching the required profile. 1. Click the co
36、mmand from the Tools toolbar so that the elements you are now going to create be either standard or construction element. In this task, you will transform the newly created elements into construction elements. As construction elements are not taken into account when creating features, note that they
37、 do not appear outside the Sketcher. Here is an example of the use of both types of elements. The hexagon was sketched using three construction circles: This type of sketch is interesting in that it simplifies the creation and the ways in which it is constrained. Setting a radius constraint on the s
38、econd circle is enough to constrain the whole hexagon. Just imagine what you would have to do to constrain hexagons sketched with no construction circles! Converting Standard into Construction Elements This task shows how to convert standard elements into construction elements and vice versa. 1. Sel
39、ect the line (standard type) you wish to convert into a construction line. 2. Click the Construction/Standard Element option from the Tools toolbar. The line you previously selected appears dotted to show it is a new type of line. Double-clicking on the line displays the Line Definition dialog box i
40、n which you can activate the Construction element option. For more information, refer to Modifying Profile Shape and Size. 3. Click the Construction/Standard Element command again. The construction line is converted into a standard line. Applying the Construction/Standard Element option on axes has
41、no effect. Sketching Simple Profiles Before you begin, make sure you are familiar with Tools For Sketching. As soon as a profile is created, it displays in the specification tree. You can sketch profiles using: the corresponding icons: the menu bar: Tasks Creating Profiles This task shows how to cre
42、ate a open or closed profiles. Profiles may be composed of lines and arcs. Remember that you can also use the value fields of the Tools toolbar. 1. Click the Profile icon from the Profiles toolbar. The Tools toolbar displays with Lines, Tangent Arcs and Three Point Arcs switchs. The Line switch is a
43、ctivated by default. 2. Click two points to create a line. A rubberbanding line follows the cursor, showing the next line which will be created. 3. Click the Tangent arc switch that is now available from the Tools toolbar. 4. Drag the cursor and click where you wish to end the tangent arc. The tange
44、ncy symbol is displayed. 5. Click the Three Point Arc switch . 6. Click two points as indicated. An arc is created. In other words, only the arc end points are created. The Line switch is set by default. 7. Drag the cursor to create a line. Now you are going to create another line then a tangent arc
45、 but this time without using the Tangent Arc switch . 8. To create an arc as part of a profile drag and release at the point where you want to begin your arc. A rubberbanding arc follows the cursor, showing the arc which will be created. The arc is automatically tangent to the previous element. 9. D
46、ouble-click in the free space to end the profile creation or click the profile starting point. In other words, you end the profile creation and close it according to the element last created. Tangent arcs are always positioned in the direction of the element previously created. Creating Rectangles T
47、his task shows how to create a rectangle by clicking. Remember that you can also use the value fields of the Tools toolbar. 1. Click the Rectangle icon from the Profiles toolbar 2. Point to where you wish the first corner of the rectangle to appear. 3. Drag to see the rectangle being created. A rubb
48、erbanding rectangle follows the cursor as you drag it. 4. Click to create the rectangle. The logical constraints detected during the creation of the rectangle are memorized. Creating Circles This task shows how to create a basic circle. Remember that you can also use the value fields of the Tools to
49、olbar. 1. Click the Circle icon from the Profiles toolbar (2D Circle subtoolbar). 2. Click where you wish the center of the circle to appear. By default, centers are created but if you do not need them you can specify this in the Tools-Options dialog box. For more information, see CATIA - Infrastructure Users guide Version 5. 3. Move the cursor to see the circle being created. A rubberbanding circle follows the cursor as you drag it. 4. Click once you are satisfied with the size of the circle. The circle is created. The specification tree displays this circle as well as its center po