CAES1507 Professional and Technical Written Communication for Engineers

Session SixTheory and Design

Feedback on Introduction The background has to be adequate to justify

the prototype invention Be sure the information about the request for

the project is correct Pay attention to the use of tenses

Background – Present and/or present perfect tense Purpose of the project – Past tense Purpose of the report – Present tense

Avoid using personal pronouns and possessive adjectives such as “I” and “our”

Feedback on Introduction Use formal tone

Bear in mind that you’re asked to design and build a prototype of the toy to be considered for mass production, NOT the toy itself yet

Stick to the requirement of the project and what you’re really going to cover in the report

Theory Other engineers need to know WHY you have

done what you have done in your design so that they can duplicate it or improve it or change it in some way

Include formulae if necessary but you must explain why you have included them.

Use theoretical principles to explain why you have made the choices you have in your first design and why you made the changes you did in your second design.

Theory PRESENT TENSE should be

used unless you refer specifically to your project, for which PAST TENSE is used

You should include graphic information.

Example – What information is included?

The simple law of gravity maintains the mousetrap in a state of rest until a mouse enters the system introducing an external force that activates it. When the mouse enters the trap, it creates a force on the system due to its weight. The force puts tension on the wire activating the other parts connected to it. See Figure 1.

A general description of the overarching theory used

Explanation of theorywith specific referenceto the prototype

Refer to diagram

Example – What information is included?

The fixed pulley in the prototype mousetrap is used to change the direction of tension in the strings. The pulley is used so that the tension of the string can be transferred from one part to another even if the string is bent or twisted.

A prototype also uses a simple lever system requiring a pivot point as shown in Figure 1.

Explanation of functions of specific parts using Engineering principles

Other relevant engineering principle

Critical Thinking How would you propose to

IMPROVE the example in the booklet?

Writing Tips1. Identify the theory/mechanism

involved in the design2. Include equations/mathematic

formulae if necessary3. Give examples to illustrate how the

theory is being applied in your design4. Include diagrams or any other forms of

graphic information which aids explanation + Label the main parts of a diagram

Questions to be answered in the Theory sections What theory or theories have you used

in your prototype design? How is the respective theory used in a

component of your prototype? Does the use of a mathematical/physics

equation help in explaining the mechanism of a component of your prototype? If so, how?

In-Class Practice Task – How do Roller-Coasters Work?

Work in groups, write the theoretical principles behind the operations of roller-coasters. Your work should include sketches of diagrams and relevant equations.

Design Identification of the major parts of

your prototype Insert graphics (overall design +

different parts) Describe the structure - major

parts (no need to include the procedures of making them, which is in fact the focus of next session)

Describing the major parts Provide a name of the part being

described Identify the major function of the part Describe the function of each smaller

component Provide the specifications (e.g. The light

bulb will glow when activated indicating a mouse is trapped)

General

Specific

Name of the major part

Function of the major part

Function of smaller parts

Specifications of smaller parts

Points to Note - Language Present Tense should be used Signposting is needed to signal the

structure of your Design Orientation –

The bottom of… On the right hand side of … On top of… Kitty corner to… At the top right corner of…

Points to Note - Language Quantity –

Two plastic wires… Three wooden boxes …

Reference pronouns – This / it (make sure the readers know

what ‘it’ refers to)

Points to Note – Graphical Representations Include diagrams (and must be

referred to in your text, e.g. Figure 1, as shown in Figure 4)

Include a caption for each diagram (e.g. Overall design of the burglar alarm)

Label all important parts

An ExampleThe overall design of the mousetrap (figure 1) can be divided into three main parts, the base, the light box and the side track. The following sections illustrate the overall and completed design including the structure and function of each part.

General Introduction of the design – the components of the prototype

Signposting – i.e what will be included in the following sections

An Example

The base in the main body of mousetrap. This is where the mouse enters and is trapped. The bottom of the base is a movable platform which is used to activate the whole system.

Introduction of the component part

An ExampleOn the two side walls, there is a wooden stick settled in a track on each side and connected to the platform by plastic string. The wooden sticks are used to lock and unlock the gate in front. The gate is a sliding section which covers one side of the base. When it is released it slides down to enclose the mouse completely in the box. On the left hand side wall, a little box which has an inclined bottom and a hole on one side is attached.

Fairly general description of the structure and mechanism

Information: Structure of

the part Function of

the part

An ExampleThis box is used to trap a marble and the marble is trapped by another wooden stick which is also connected to the platform by wire. Two plastic wires are connected to the platform and then to the light box. The structure of the base and the inner mechanism of the base are shown in Figures 2 and 3.

Always refer to relevant diagrams

Present Tense is used

Comparison – Which description is better? Read the other version of the

discussion of the Light Box design on page 31. Compare this version with the original on the same page. Which one do you think is better? Why? (Hint: think about the logical development)

Version one Function of the box

How it works

Size of the box

Mechanism

Refer to figures

Version Two Refer to figure 4

Size of the box

Function of the light box

How it works

Refer to figure 5

Mechanism

General

Specific

The Side Track1. consists of2. used3. are activated4. is released5. rolls and falls6. to make contact7. show

Is made up of + people/materials

Is made of + materialsIs made by + people

Homework Write the Theory section in group outside class. Hand

in the hardcopy to the class teacher in the next lesson.

Start building the prototype for demonstration in Session 8.

Start drafting the Design section in group outside class. You will be required to hand it in Session 8.

Secretaries of the second meeting need to hand in the minutes (in hard copy) in the next lesson. Make copies of your minutes for your group members.