Daily Calendar | TDJ2O Info | Sketching | Engineering (2D/3D) | Industrial Design | Architectural Design | Summative Project 

Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes.

The key in good design is that our ideas should stem from principles of engineering as much as from artistic form and function. That is, the object should not only look good, but it should function under a variety of conditions all predefined by our materials choices and object's structure.

To that end, in the generation of ideas we use AutoCAD and other 2D modeling software to create blueprints from which to work. Blueprints are a roadmap from which a person building an object can ensure every last detail of the original design can be followed. Named by the process by which they were replicated prior to the invention of large plotter and printers, a blueprint includes all relevant details of construction from component sizes, to assembly, to material choices and tolerance.

AutoCAD

AutoCAD (computer-aided-design) is a high-end program that is used by designers the world over to realize their ideas. AutoCAD not only allows you to design in 2D and 3D but it also has, as output options, the ability to send information from your designs to CnC routers, and 3D printers for modeling.

We will explore the basics of AutoCAD as a tool in our design arsenal.

We will follow this basic reference guide as we begin to head through the world of AutoCAD. 

Here is how it works:

AutoCAD uses points to determine the location of objects, with the origin (0,0) as the starting reference. The X-axis extends to the right (positive X coordinate) and the Y-axis extends upward (positive Y coordinate). For example, a point at (4,8) is 4 units to the right on the X-axis and 8 units up on the Y-axis, while a point at (-4,-2) is 4 units left on the X-axis and 2 units down on the Y-axis. A line in AutoCAD has two points: a start and an end, displayed using these coordinates. To draw relative lines from an existing endpoint, you use the "@" symbol. Typically, when using a mouse, you don't need to worry about exact coordinates, just the position of your endpoint. That is to say, you can enter text through the interactive cursor and ignore the mouse cursor, OR the mouse cursor, or some combination of the two.

There are a number of direct practical outputs from your 2D AutoCAD drawings. We can print them out to use as blueprints for building, share them as computer graphics (pictures) to convey an ideaor to use as a working plan for a project - both of which we'll do in future projects. However, the next step for us is to take our CAD drawings and output them directly to an interface that will allow us to 'cut them out' in a material of our choice. To do this we'll be using a CnC router. A CNC router (CNC stands for computer numerical control) is a numerical control tool that creates 3D objects from various materials.

Projects are typically designed on a computer with a CAD/CAM program, and then cut automatically using a cutting tool in a router. The CNC router works like a printer, in that a set of instructions are sent from the CAM/CAD program to the CNC router for the hard copy. Because the CNC router uses a cutting tool that can cut in all 3 Cartesian coordinates (Z depth as well as X and Y), the output is a 3-dimensional copy of the work. The cutting tool is generally a router with various shapes/sizes of routing bits, but other cutters can be used as well. The CNC Router is ideal for hobbies, engineering prototyping, product development, art, robotic education, and production work. 

vCarve Pro

We will be using vCarve Pro to interface between our work in AutoCAD and our output to the CNC router. The vCarve interface is fairly simple. We will be using this explanation document (PDF warning) to supplement our in-class tutorial on the functionality of vCarve.

Simplistically - vCarve will either open a dwg (AutoCAD) drawing and we can use the vectors from our drawing to create toolpaths (what the CNC will cut for us) OR it will create vectors for us from a picture to cut on the CNC. The general workpath for using the CNC is:

1. Create vectors of the drawing in vCarve (either from importing an AutoCAD file, or using the bitmap trace functions within vCarve on a picture from the internet)

2. Select the region you want to vCarve on the CNC

3. Specify tool information (which includes the tool type [flat vs. beveled], depths, starting location etc...

4. Virtually preview the toolpath as it was actually being cut

5. Save the toolpath (txt file for our router which is a Mach) onto a USB stick

6. Place the material in the CNC router and set the starting point (typically the bottom left corner).

7. Allow the CNC to cut the design.

Technological Reports

[Exemplar of what it would look like]

1. Title Page

The title page is used to grab the attention of the reader. As such, it should contain some form of illustration that appeals to the reader. It should also contain the name of the report, the person or people involved in the group,the course code and the date of production (the due date is best).

2. Situation (The Problem)

The situation sets the stage and informs the reader about what is being solved and why you are doing the report/project. It may state the identified needs and problems of the project at hand. Describe the problem with all relevant information available as guidelines and/or rules.

3. Research & Design description

The research is a gathering of all the information found on the product about to be built. The research should include as much information as possible on the history of the product, the use of the product the physics involved in order to make this product work and the pricing of the real product. You are allowed to use images as visual aid in your research, but copy pasting any article found on the Internet or any other means of resource will not be evaluated for marks.

The design description is an in-depth account of the process used in the design and fabrication of the product. The sentences in each paragraph should be kept short and to the point. It describes the route used to determine the solution to the design challenge. Include references to your research. Make sure your description is clear and precise, so that if need be someone else could build your article. Don’t just give a sequence of how you assembled the artifact.

4. Materials

List all the materials, sizes and costs (if applicable) used in the fabrication of the final product. As much detail as possible should be given.

5. Drawings or Illustrations

Include all drawings or illustrations that were used in the development and fabrication of the project. This includes thumbnail sketches, rough sketches, technical drawings, illustrations, and/or photographs of models or products. Ensure all drawings are properly labeled and descriptive.

6. Conclusion

Describe what you learned in this design challenge. Include the results of testing solutions. Include a description on how each of the design criteria was met (or not). Why did it succeed? Why did it fail? Describe possible improvements or modifications for future work. Include what would you would not do next time? Suggest other users or situations that may benefit from your research and/or testing. 

3D modeling is the process of developing a mathematical representation of any three-dimensional surface of object (either inanimate or living) via specialized software. The product is called a 3D model. It can be displayed as a two-dimensional image through a process called 3D rendering or used in a computer simulation of physical phenomena. The 3D model allows designers to problem-solve, share their ideas in a more tangible way with other people, and lastly, to export to 3D printers - if the materials allow it.

All 3D programs share the same basic components in that they have to represent 3D space in 2 dimensions. The solution is to use projective geometry which transforms shape vectors (lines, curves, spheres, boxes etc...) into a 2D line which can be displayed on the screen. These lines are often colour-coded, or displayed with alpha-dissolves (same colour, but made more faintly) to make it easier to see the dimensions on the screen for the designer.

Some 3D modeling programs include Sketchup, form-Z, Maya, 3DS Max, Blender, Lightwave, Modo, solidThinking, SolidWorks and many more.

We will be using Sketchup for our 3D modeling. Not only is it free, but it has quite a powerful set of tools available to us that are fairly intuitive. 

Some tricks to using Sketchup

• Always ensure that you're using lines that follow the x, y, and z axes. The lines will flash green, red or blue if you're drawing correctly down one of these axes.

• When possible, draw a guide before drawing a line/shape. It will ensure you get the correct distance. You can draw a guide by using the tape measure tool (toggled with control to get the 'plus' symbol), or the protractor tool for an angle (toggled with control once you've decided the angle reference).

• Middle-mouse (MMB) click orbits your project, while holding shift+MMB allows you to pan your sheet in the current view (slide it around).

• Spacebar is the universal 'get out of here' shortcut (much like the Esc. key is in AutoCAD). It allows you to select lines or deselct lines.

• While selecting, holding Shift down allows for multiple selections.

• Dragging a marquee box to the right functions just like in AutoCAD (makes a selection if the selection is completely within the marquee). Dragging a marquee box to the left selects anything that falls even a little bit within the marquee (again, just like in AutoCAD).

• In complex objects - ensure your layers are open and you're putting each new element on a new layer. E.g. - in a house drawing, the walls may be in one layer, while the floor is on another, and the roof on yet another.

• When push/pulling an object - toggle a new face by hitting Control before starting your push/pull. This creates a new face and doesn't leave a mess later on.

• Work in the extended toolbar mode and learn your shortcuts!!!!

Common errors and how to avoid them (pdf warning)