The document describes a "clamshell" backpack organizer designed to protect valuables from impact. It features a solid clamshell design with a gasketed lid to prevent water from entering. An interior loop allows convenient wall or carabiner storage. Interior inserts can further protect items. Study hinges and a latch keep the case closed during activities. The document then discusses how AutoCAD was used to design the organizer, including sketching, modeling in model space using lines and geometry tools, and annotating in paper space per technical standards.
2. “Clamshell” Backpack Organizer
Backpack organizer featuring a solid “clamshell” design
keeps all your valuables safe from impact. A gasket under
the lid prevents rain from getting in. The side loop allows
for convenient storage on a wall hanger or carabiner.
The interior of the case allows room for user created 3D
printed inserts to further protect delicate items such as
phones, headphones, money, papers .etc. Study hinges
and a latch mechanism keep the case closed while hiking,
biking, running, or traveling.
8. Creation of the Part
While creating this part, many features of AutoCAD had to be used. A few, but not all, examples
include:
● Creating a hand drawn sketch to flesh out the overall design
● Learning core concepts in the Model Space
○ Linetypes and lineweights
○ The Draw Toolbar
○ The Modify Toolbar
○ Snaps and Grid
● Learning core concepts in paper space
○ Creating annotation per correct ANSI/ASME/ISO standards
9. The Hand Drawn Sketch
Most part design starts with a hand drawn
sketch. While the sketch is never drawn to
scale and may not even contain the final
dimension, it is necessary to determine the
feasibility of the overall product. The
sketch is a crucial bridge between the
designer and whoever ultimately
manufacturers the part.
10. Model Space: Linetypes and Lineweights
Creating a 2D representation of a 3D
model would be impossible without a
variety of linetypes and lineweights.
Linetypes are mostly made up of dots and
dashes and can be used to represent
visible lines, hidden lines, center lines,
section lines and much more. Line Weights
are critical in differentiating the feature of
a part.
All of these standards are set by the Layers
toolbar in AutoCAD.
11. Model Space: The Draw Toolbar
The Draw Toolbar contains most of the
tools to create a part. A model will usually
start with the line, circle, arc, or rectangle
tools. The Construction line is a
particularly useful tool that allows the
designer to create lines of infinite length
that can easily be hidden latter on. These
lines ensure that all orthographic views
align correctly in the model.
Here construction lines are represented in
blue.
12. Model Space: Modify Toolbar
Once the designer has created the basic
outline of the model, it’s time for the Modify
Toolbar. This toolbar contains tools such as
trim, copy, mirror, fillet, and scale. Without
these tools the designer would have to spend
hours creating features with simple line and
arc tools from the Draw Toolbar.
The fillet is probably the most common
refinement tool used in CAD design.
13. Model Space: Snaps and Grid
The Grid in model space allows an AutoCAD
designer to easily lay out the dimensions of a
part. Object Snaps are particularly useful.
They allow the drawing of features to
endpoints, midpoint, centerpoints,
tangencies, and more.
An example of all the object snaps for 2D
modelling.
14. Paper Space: Annotation
Paper Space is where the final dimensioning
of the drawing takes place. This drawing is
what ultimately goes to the shop floor for
production. Maintaining the correct
ANSI/ASME/ISO standards is critical when
producing the drawing. Also, a border is
created in paper space that contains
information such as the drafter’s name, the
scale, the date the drawing was created, the
page number, any general notes, and so on.
An example of the dimensioned right side of the
lid featuring length, radius, and diameter callouts.
15. Conclusion
ENGT 100 taught me the basics of
the AutoCAD software. I feel that I
could interpret a drawing and make
modifications if needed. I can model
basic parts in AutoCAD, but for
complex parts I would prefer a 3D
CAD program like Catia. Because of
the 2D nature of AutoCAD, I feel
that I understand paper drawing
better than I did before starting the
quarter.