|
|
|
Activity 4.4 – Reverse Engineering
Purpose
Today, when you purchase a product, you very seldom get the chance to see how it was made. Have you ever wondered how something works? Have you ever taken something apart so you could find out? Have you ever wanted to do just that?
With the use of your skills of sketching and using computer software, you will be able to explore how an object was originally put together. Your first reverse engineering project will involve looking at an object that is made out of wood or metal. You will look at it from all views and try to determine what different shapes make up the object and then to try and reproduce it from what you are able to determine from your observations and measurements of the object.
Reverse engineering is used by many engineers to study an object and to make innovations or changes to an existing product. You will find it helpful when you want to learn how something works. If you can take something apart, you generally realize it is made up of simple shapes and is not as complicated as it first appears.
Equipment
· Sketch paper
· Pencil
· Ruler or scale
· Engineer’s notebook
· Computer with appropriate software, such as Inventor
Procedure
You and an engineering team
member will be given an object. Maybe you’ll be given a wooden block that
looks similar to Figure 1.
First, accurately describe the object
without reference to measurement and record your description below. Check with
your teammate to see if you are seeing the object from a different point of
view and adjust your description.
Next, you will create a sketch
of the object. Using the measuring device (i.e., ruler or caliper)
provided, accurately measure
the object to the nearest sixteenth of an inch, placing the dimensions on your
sketch.
Work as a team and double check your answers by
comparing your measurements with your engineering partner.
When sketching, look closely at the object and
determine the basic shapes that make up the object, such as a square,
rectangle, or triangle.
Your teacher may ask you to place your sketch in
your engineer’s notebook. Have your teacher review your sketch before you
move to the next step.
Next, you will create an orthographic
and an isometric drawing of
the object.
Work as a team and double check your drawing by
comparing the views that you have drawn.
When drawing, be
sure to choose your front view for the orthographic sketch carefully.
Determining factors could be function or least amount of hidden views.
Your teacher may ask you to place your drawings in
your engineer’s notebook. Have your teacher review your work before you move
to the next step.
Using
the appropriate software, such as Inventor, make an accurate computer model from
the sketch and measurements you made. Check with your teacher if you have
questions about the process.
Remember
the steps of using the software you learned during the tutorial on sketching,
constraining, and extruding.
Try to think of the
simplest way of doing it and it probably will be the best way. Using the
example, Figure 1, the approach would be to sketch a rectangle – constrain
with dimensions
and then to extrude to the correct depth.

Continuing
using Figure 1 as an example, choose the front of the figure to add the front
sketch. Sketch the added rectangular shape to the lower left
corner, constrained with
dimensions and extrude to proper depth.
The final procedure is to
draw on the surface where there is an angular cut. Sketch the line, constrain
with dimensions, and
extrude but this time use the cut operation to remove the shape.

The finished 3D computer Model

Conclusion
1. What is different about doing reverse engineering versus creating a drawing from an object you have not seen made?
2. How do you think the use of reverse engineering would help you when you are working on solving a problem?