Exercise 2 - Computer Aided Design
The assignment for this week is explore different types of design software and use them to model my final project.
In the beginning, I was puzzled why there is a need to even try out different software. I believe being an expert in one is better than “a jack of all trades but master in none”. However after the lesson and explanation from my coach, Steven, I begin understand the different types of software (such as 2D raster, 2D vector, 3D CAD, simulation, animation, audio and video editing) and their area of applications.Due to the short time frame, I decided to explore one software in each category.
For 2D Raster, I tried GIMP
I have been using Irfanview image viewer by Irfan Skijian for several years to do simple image manipulation such as cropping and resizing. While Irfanview is free and extremely easy to use, as an image viewer, there is little functionality to do photo-retouching apart from adjusting contrast, brightness, gamma and etc. It is also not able to do draw and sketching.
Thus for the 2D raster software I decided to learn GIMP
primarily for sketching and drawing. I downloaded GIMP 2.10.14
directly from http://www.gimp.org.
Sketching with GIMP using a mouse is not as easy as I thought to
be. It tool me more than 3 hours just to draw this simple side
view of the blender cup and my final project idea.
For 2D Vector, I tried Inkscape
Inkscape is a 2D vector drawing program. Inkscape manipulates object using a series of mathematical equations unlike GIMP which works at the pixel level. I downloaded from Inkscape.org
After going through the 4 tutorials on Inkscape.org page, I
started drawing. While the tag line for Inkscape is “Draw
freely”, it is not at all free. There is a lot of unlearning and
relearning to do. For example, deleting function is very
different. Even after separating an object into 2 by deleting
the middle portion, the object still remains as one single
entity. To separate the two halves, the command “Break Apart”
under the "Path" pulldown menu must be used.
Another feature Inkscape that I explored is the Trace Bitmap.
It is useful for converting a raster (bitmap) to a vector.
Inkscape has an automatic tracing tool that makes it to
vectorize bitmap images. While operation is simple, it takes a
lot of practice to know what mode and setting to use in order to
get a good vectorise image. 
3D CAD Software - I tried Fusion 360
Fusion 360 by Autodesk is a cloud-based CAD/CAM tool for collaborative product development. As I was previously introduced to Fusion 360 briefly, I decided to learn this software as it is less daunting than the rest. My plan is to explore FreeCAD in the near future one I am comfortable with Fusion 360. Fusion 360 is also free for students and teachers, thus I can enjoy its full functionality without having to pay. I am currently using Shapr3D on my IPAD together with IPencil. Shapr3D is extremely powerful and easy to use, unfortunately it is USD240 per year!!!
The figure above is what I created with my IPAD. For the free version, I can only export low resolution files in STL format.
After watching several YouTube tutorials by Kevin
Kennedy and Paul
McWhorter, I began my journey of learning how to use
Fusion 360. Learning would be very daunting without the
tutorials on Youtube. After several attempts, I was finally able
to create the body for the first part of my final project, the
receiver box. What I love about Fusion 360 most is probably the
Right mouse click which opens up a range of command as shown
below:
One challenge I had was to create the curve surface on one
side of the box so that it can sit firmly on the blender cup. To
do so, I learnt how to use construction lines to locate and mark
out the centre of the curvature.
To create the box and its cover, I use the create menu
(rectangle, offset, circle) to draw the basic shape in 2-D and
use the Pull function in the Modify menu to create the box and
Fillet to smoothen the edges. To create the cover, I have to use
the Off-set panel under the Construction Menu before I can start
drawing. I also used the Combine function under modify to fuse
two parts into one as shown in the picture below. 
I am happy that I was able to create the receiver box and its
cover using Fusion 360 which is quite similar to the one I
created with Shapr3D. 
3D Model
Result:
Result
The next stage is to model the magnet holder using
Fusion 360. I am still learning how to intercept a cylinder rod
with a rectangular block. I have done this with Shapr3D as
below:
