Step 1



Parametric Design Technology

Activity 1

Using the ProDESKTOP

Objective

Today you will take the pre-test to see what information you already know about Parametric Design Technology. You will learn the basics of parametric design including drawing tools, workplanes, extrusions, shells and constraints

Step 1

Taking the Pre-test

This is only to see what you already know.

Step 2

Reviewing Vocabulary Words

This activity includes the following vocabulary words. List them on your vocabulary/study question worksheet. Look for them as you do the activities in today's lesson and write the definitions in your own words.

1. Parametric Design

2. Conceptual Engineering

3. Constraints

4. Sketch

5. Extrude

6. Shell

Step 3

Reviewing Study Questions

Read the study questions and look for the answers in this activity. When you find the answers, record your answers on the vocabulary/study question worksheet according to your teacher’s instructions.

1. Parametric Design allows you to design and draw in _____________.

1. 1 dimension (1D)

2. 2 dimension (2D)

3. 3 dimension (3D)

4. no dimensions

2. The constraints of your drawing allow you to set the ________ of your object?

1. size

2. quality

3. image

4. shape

3. Which view of the design allows you to see you drawing in all three dimensions?

1. Workplane

2. Isometric

3. Trimetric

4. Elevation

4. A cuboid is created using which of the following methods?

1. sweep

2. revolve

3. loft

4. extrude

Step 4

Information

Parametric Design - a system that constructs relations among the geometry of different elements. When one element is changed, the geometry of the rest of the elements is changed as well. Parametric design has changed the way products are being designed and prototyped.

[pic] [pic] [pic]

[pic] [pic] [pic]

Conceptual Engineering - resources that allow you to develop ideas at the earliest stages of the design process, without getting bogged down in specifications; systems that

allows you to quickly explore design possibilities and rapidly capture ideas.

By using Pro/DESKTOP parametric design software:

• students learn about how products are designed, refined, and produced

• students use visual skills and develop sensitivities and sensibilities about aesthetics in product design

• students exercise and develop their creative potential by imagining what might be and bringing it closer to reality or, in many cases, bringing it into reality through modeling and CNC prototyping.

Step 5

Design Scenario

In this exercise you will be introduced to the three main functions of Pro/DESKTOP. During the process you will create a simple building block for a child's construction kit. This will form the basis for a texture-mapped image and an orthographic engineering drawing.

Scenario: A company that currently manufactures rubber components for the automotive industry is looking to diversify their business. They have contacted your design company to develop a child's building block that can be made from recycled rubber bumpers.

The company would like to use their existing production equipment, namely their injection moulding facility.

Your designers have come up with several possible children's building blocks. In the next step, you will be developing a 3D model of a desired block.

Step 6

Using Pro/DESKTOP Modeling

Beginning a New Drawing

1. Double click on the PTC Pro/DESKTOP 8 icon [pic] on the desktop.

2. The following window will appear:

[pic]

Note: You may need to maximize the window by clicking on the icon in the upper right corner of the window as indicated.[pic]

3. Click on the New Document icon [pic]

4. The New dialog box will appear.

[pic]

Select Design and click OK.

5. The following window will appear.

[pic]

Note: Will need to maximize the design window by clicking icon in the upper right corner of the window. See example: [pic]

6. You now have the following design window to work in. The green rectangle in the modeling/design window indicates a workplane and the bold green arrows appear at the origin. Remember that the origin is the point where all axes intersect and are represented by (0.0)

[pic]

Step 7

Using Pro/DESKTOP Modeling

Choosing the Proper Units

1. By default the Pro/DESKTOP software units will automatically start up with the same units that were used for the very last design. Remember that you are not the only students using this program. Although most of the world uses the metric system of measurement for this project you will be working in inches.

2. Pull down the TOOLS Menu and select Options. [pic]

3. The Options dialog box will then appear.

4. [pic]

5. You should then click on the Units tab at the top of the box. This will bring up the following box. See example

6. .[pic]

7. Set the Model distances to Inches (in) and the Paper distance to Inches (in). Click OK when finished. You are now ready to begin your 1st drawing.

Step 8

Using Pro/DESKTOP Modeling

Creating Solid Objects

1. The first stage in creating a 3D object is to draw a 2D sketch. This sketch will then be used to create a 3D solid shape. See examples of 2D and 3D objects below. (Do not attempt to draw at this time - you will begin drawing in the next steps.)

[pic] [pic]

Rectangle Sketch Sketch extruded into a block

2D Sketch 3D Solid

2. Drawing Tool Identification - All 2D sketches are created using the basic sketching/drawing tools of Pro/DESKTOP. Those drawing tools are explained below:

[pic] Straight Line - Hold shift while drawing a line to keep the line parallel to an axis.

[pic] Circle

[pic] Rectangle - Hold shift while drawing a rectangle and you will have a square.

[pic] Ellipse - Remember an ellipse is an elongated circle.

[pic] Arc or Fillet - A fillet is the rounding of a corner.

[pic] Spline - A spline is an irregular shaped object that uses various lines and arcs.

3. Your sketch will be drawn on the base workplane. This is the workplane that appeared when you opened the new drawing. Select the Rectangle [pic] from the drawing tools.

4. Draw a rectangle on the workplane by clicking and dragging with the mouse. Notice that the workplane resized to surround the rectangle you have drawn. Don't worry about the size of the rectangle at this moment, we will be setting the size later in this activity.

[pic]

5. Without realizing it ProDESKTOP is creating hidden constraints as you draw. The rectangle has perpendiculars in each corner and parallels on opposite sides. To make these constraints visible click on the Select Constraints tool [pic]. The constraints show as small marks in the corners and along lines. You may recognize them from your math lessons.

[pic]

6. Before you proceed you should save your work. Click on the SAVE icon [pic] it looks like a floppy disk. The following window will appear:

[pic]

7. Select the appropriate class period folder from the My Documents folder. Then click the open button. Next, type in your file name. Save your file using both of your first and last names followed by the number 1. Example: Sam Smith Jane Doe 1. Finally, click the Save button.

Step 9

Using Pro/DESKTOP Modeling

How to Change the View

1. Changing the way you view the model as it develops is an important skill to learn.

2. The VIEW pull-down menu contains a number of different options.

[pic]

Try these options and become familiar with how they work.

A. Half Scale: allow you to reduce the size of the object on screen by half.

B. Zoom in: allows you to enlarge the object or a portion of the object you are drawing. When using the zoom in feature you should click at the center of the par you wist to enlarge and drag the mouse making a box around the area you wish to enlarge.

C. Manipulate: allows you to revolve and rotate the object so that you can see it from different sides.

D. Autoscale: zooms the object to the largest possible size that will fit on the screen. This is a very helpful tool if you loose your object while using the view commands.

3. You can also change the view to view directly down Onto Workplane. To change to this view you can hold down the SHIFT key and press the W on the keyboard. The screen is now viewing down onto the workplane. You may need to expand or reduce the drawing to fill the screen. You can access Autoscale by holding down SHIFT and pressing A. Your view should be like the following example:

[pic]

Step 10

Using Pro/DESKTOP Modeling

Adding Sketch Dimensions (Constraints)

1. You will now change the size of the rectangle by adding sketch dimension constraints. Select the Add Sketch Dimension (constraints) tool [pic]

2. Click on the left-hand line and drag away from the rectangle to position the length constraint. See example below: (Note: Your number and the example will not be the same.)

[pic]

3. For the width constraint you will use an alternative method. This technique gives you more control over the precise constraint created.

4. Make sure that the Add Sketch Dimension (constraints) tool [pic] is still selected.

Note: If any of the lines in the rectangle are highlighted in red, click on a blank part of the design window to deselect them. Note: If you click on a blank area of the screen when nothing is selected the Add Sketch Dimension tool will de-select.

5. Click once on the left hand line of the rectangle you have drawn (not the workplane - the workplane is green). The left side line will turn red.

6. Click on the right hand line and drag downward to create the constraint. It should resemble the following example:

[pic]

Note: The size of your lines and those examples in the book will not be the same. We have each drawn a rectangle and the size is the actual size of the one you have drawn.

7. This technique will allow you to create constraints between lines, endpoints and intersections between lines.

8. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 11

Using Pro/DESKTOP Modeling

Changing the value of a Constraints

1. Now that you have identified the sketch dimensions of your rectangle, you will be making the rectangle a specific size.

2. Click on the Select Constraints tool [pic].

3. Double click on the text (numbers) of either of the constraints/dimensions.

[pic]

The following dialogue window will appear:

[pic]

4. Change the Length (in) to 12. Then click OK.

Note: Do not change the name of the variable.

5. Repeat this procedure with the other dimension constraint.

6. You should now have a square that is exactly 12 inches on all side.

[pic]

7. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 12

Using Pro/DESKTOP Modeling

Extruding the Object

1. Things will really get exciting now. You are ready to use the Extrude feature to create a solid object. The extrude feature creates a solid from a closed flat shape. It works like squeezing toothpaste out of a tube. The toothpaste exits the tube in the shape of the opening.

2. Begin by changing the view to Trimetric. Do this by holding down SHIFT and pressing T. The trimetric view allows you to see your objects length, width and height - a 3 dimensional view.

[pic]

3. Click on the Extrude tool [pic]. The extrude dialogue window will appear:

[pic]

4. You could now type in an extrusion distance. However, an alternative method is to drag the extrude 'handle' to define the extrusion distance dynamically. The extrude handle is the small yellow square in the center of the rectangle. Note: If the dialogue box is hiding the extrude handle, move the dialogue box by clicking and dragging the title bar of the window.

[pic]

5. Click on the small yellow extrude handle, and drag it upwards until the extrusion distance settles on 12 inches. Note: You may need to pause as you drag to allow the computer to catch up. It is doing some heavy calculations! Release the mouse button.

[pic]

6. Click OK. You should now have a cuboid like the example below:

7. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 13

Using Pro/DESKTOP Modeling

Adding a Taper

1. One of the most powerful features of ProDESKTOP is the ability to edit or change almost all of the work you have done so far. The playground block will be injection molded. For the component to be removed from the mold easily it must be slightly tapered. This is called a draft. This section will show you how to alter the extrusion to create a tapered shape.

2. On the left side of the ProDESKTOP screen is the browser. It currently shows a list of workplanes in your model. See example:

[pic]

3. Click on the arrow, next to Workplanes to open the browser list. [pic]

4. Select Features from the browser list.

5. Features are the 3D operations that create solids from sketches. The browser now shows that only one 3D feature has been created, an extrusion. See below:

[pic]

6. In the browser move the mouse cursor over the extrusion "Extrusion 1" and right click the mouse button.

7. Select REDEFINE from the floating menu.

[pic]

8. The extrude Profile window will appear:

[pic]

9. Set the taper angle to 3. Then click OK. Your model will now be tapered 3 degrees. See example: [pic]

10. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 14

Using Pro/DESKTOP Modeling

Rounding the Edges

1. When developing blocks to be used by young children, safety is a top priority. Companies must make every effort to ensure that the items do not cause injury to the children. The sharp edges on the blocks we are designing may be a safety hazard. You will eliminate the problem by adding curves to the external corners.

Sharp corner can also cause problems with the flow of plastic in moldings so there is an added incentive to radius the transition between adjacent flat surfaces.

The round tool will radius the highlighted edges on existing solid objects.

2. Click on the Select Edge tool [pic] from the right hand tool bar.

3. Move your cursor over one of the vertical edges. It will appear blue when highlighted. Click the mouse once and the edge will turn yellow and then red when you move the cursor.

[pic]

4. Hold down the SHIFT key and continue to click on the other three vertical edges to add them to the select edges.

[pic]

5. Continue holding the SHIFT key and add the four top edges to the selection. All selected edges should appear as red lines.

[pic]

Note: If you have problems highlighting the correct lines click on a clear area of the screen and begin the highlighting again.

Also, do not select the bottom edges of the block.

6. Click on the Round Edges tool [pic], from the top toolbar.

7. The following dialogue window will appear:

[pic]

8. Set the Radius (in) to 0.5 and click OK.

9. Your block should now have rounded edges and look like the following example:

[pic]

10. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 15

Using Pro/DESKTOP Modeling

Creating a Shell

1. If you were to injection mold our block it would contain a lot of plastic. This would make it heavy and very expensive. Most plastic moldings are hollow and try to maintain a constant wall thickness to avoid uneven contraction during the cooling period after molding.

ProDESKTOP has a tool that will hollow out a solid called Shell. Before choosing the shell tool you must have a face selected that will become the "opening" into the solid.

2. The opening of your block will be in the base of the block. Use the up arrow key on the keyboard to rotate the block until you can see the base.

3. Click on the Select Face tool [pic], from the right hand toolbar.

4. Move the cursor just inside the bottom face of the block. The perimeter edges will be highlighted in blue. Click the mouse button and the base will turn red, letting you know that it is selected.

[pic]

5. Click on the Shell Solids tool [pic], from the top toolbar. The following dialogue window will appear:

[pic]

6. Set the offset (in) to 1. Then click OK. Do not change the feature name.

7. You block should now look like the following:

[pic]

8. The block is now hollow with a constant wall thickness, better suited to injection molding.

9. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

Step 16

Using Pro/DESKTOP Modeling

Creating New Features

1. You will now design how this block will join to another block. You will be creating a "modular unit", a standard size feature that will mate with other shaped blocks that have been created using the same size standard.

So far you have used a sketch already provided on the base workplane. You will now learn how to create a workplane and sketch on the face of an object. This is a very powerful technique and one that you will use very frequently.

This technique of creating a workplane and sketch on a face works in two stages. The face you want to draw on must first be select and then the new sketch and workplane created.

2. Click on the Select Face tool [pic], from the right hand toolbar.

3. Click on the top face of the block, it will turn red when selected. You may have to rotate the block to see the top face. See example:

[pic]

4. Pull down the Workplanes menu. See example:

[pic]

5. Select New Sketch.

6. The New Sketch window will appear. See below:

[pic]

Change the Name to Bump. Make sure that Create Workplane is selected and name the workplane Top of Block.

[pic]

Click OK.

Note: It is a good practice to use appropriate names for workplanes, sketches and features to make subsequent editing easier.

7. A new workplane and sketch are located on the top face of the block with the origin located in the center. You will not be able to see the workplane yet. This is because the Select Face tool is still active.

8. Click on the Select Line tool [pic], from the right hand toolbar. This will make the new workplane visible. Remember that ProDESKTOP hides information that is not needed for the active tool.

[pic]

9. Information about sketching: The previous sketch was a simple square or rectangle. In order for a sketch to be a valid shape for creating a 3D feature it must be made up of a single perimeter line with no gaps, over laps or "spare" lines. See the examples below:

[pic] [pic]

Valid Sketches Invalid Sketches

10. You will now create a sketch on the Top of Block Workplane. Begin by changing the view to onto Workplane by holding SHIFT and W and Autoscale by holding SHIFT and A. See below:

[pic]

11. Click on the Circle tool [pic], from the right hand toolbar.

12. When drawing a circle you begin with the center and increase to the desired radius. Use the green axis lines to find the center of the top face. Place the center of the circle at the origin of the axis click and drag outward. See example:

[pic]

13. You now need to constrain the size of the circle. Click on the Sketch Dimension tool [pic], from the right hand toolbar.

14. Click on the edge of the circle and drag outward to create the constraint.

[pic]

15. Click on the Select Constraint tool [pic], from the right hand toolbar.

16. Double click on the text (number) of the diameter constraint. [pic]

The properties dialog box will appear:

[pic]

17. Change the value of the diameter to 8 inches. Click OK. Note: Be careful if the constraint is to the radius instead of diameter the radius would be 4 inches. Your workplane should now look like the following:

[pic]

18. Click the SAVE icon [pic] to update your file.

19. Change the view to Trimetric by holding SHIFT and T.

[pic]

20. Click on the Extrude Profile tool [pic], from the top toolbar.

21. Set the extrude distance to 1 inch and click OK. Your drawing should appear as follows:

[pic]

22. Your basic block is now complete. In the next two activities will use the model to create rendered images showing materials and formal orthographic (engineering) drawings.

23. At this time you should update your saved file. Click on the SAVE icon [pic]. Remember that you will not be asked to name the file this time - you are only updating the file you already created.

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