The Technological World

Exploring How Technical Objects Work

Technological World Sub-Units

1. Engineering– What engineers do– Their tools– Diagrams & documents

2. Technological Systems– What a system is & its components

3. Forces and Motion– Types of motion & their origins– Motion transmission & transformation

Why do we learn about technology?

• How many technological objects have you used today? Make a list.

Engineering

• What is engineering?• What do engineers do?

What is engineering?

• Engineering comes from the Latin ingenium meaning “talent” or “ability”.

• A branch of science and technology that focuses on the analysis and execution of technological projects such as building bridges, roads, bicycles, cars, televisions, etc.

• It is divided into various areas of specialization, including civil engineering, computer engineering, and electrical engineering, mechanical engineering, etc.

What do engineers do?

• Engineers design, and execute technological projects. They usually work as a team, each member with specialized skills.

The Design Process

• In industry, the design process consists of 3 phases:1. Design – developing a project for purpose of creating a

product2. Production/manufacturing = all operations resulting in

the construction of an object conceived by designers3. Marketing = introduces the manufactured object to the

people who might need it

• Engineers are involved only with the design phase and the first stage of the production process, but they must be aware of the processes involved in marketing & take them into account when designing.

A Closer Look at Steps in the Design Process

1. Design:– Identify a need– Analyze the technological problem– Has the problem already been solved? (if yes, present

existing solution)– Write a set of specifications– Prepare a design plan– Manufacture a prototype– Test the prototype: does it meet specifications?– Apply for a patent

2. Production:– Prepare a manufacturing process sheet– Prepare a flow-process grid– Manufacture the product– Write an instruction manual & maintenance

manual

3. Marketing:– Market the product– Maintain the product– Discard or recycle the product

Specifications

• A written document called set of specifications (a manual) is prepared before any tech object gets manufactured. It is a report which describes the nature & purpose of the desired product.

• It includes:– Function of the object– Requirements for manufacturing, use & maintenance– Standards the object must meet (a set of rules set by specialists)– Object’s characteristics– Manufacturing costs– Completion deadline for each stage– Project’s feasibility (Is the project possible, taking into account timetables,

technical knowledge, as well as political & financial situation?)

Technical Diagrams

• Technical diagrams are used in the design phase.• They explain the functioning & essential

elements of the object• Used in creating a prototype (the first copy of an

object which can serve as a model for testing).• There are several types of technological

diagrams. The 2 you will learn about are:1. Design plan2. Technical drawing (a.k.a construction diagram)

Exercise 2: C-Clamp

Standard symbols

Assisted Exercises:

Original material created by Emmanuel Fournier

13

Technical Drawing/Construction Diagram for a C-Clamp

Materials Legend

Steel

Fixed Jaw

Moveable Jaw

Adjusting Screw

Handle

Frame

What are the similarities & differences?

Design Plan for a C-Clamp

Bottom View

F

Fixed Jaw

Moveable Jaw

Frame

Handle

Adjusting Screw

Original material created by Emmanuel Fournier

14

Design Plan

Design Plan is

Simple (like a stick figure drawing)

It explains forces and movements of the technical object

A Design Plan must have the following elements:

Standardized symbols

2. Labels.

3. Motion arrows (skinny)

4. Force arrows (thick)

5. Links and guiding controls.

1. Different colors for different parts.

15

Technical Drawing/Construction Diagram

Construction diagram is

Detailed (shows the exact configuration of the object)

It tells you how to build the object in real life.

A Construction Diagram must have

Standardized symbols

2. Labels.

3. Show materials used (with a legend @ the bottom)

4. Measurement arrows and extension lines

5. Links and guiding controls.

1. Different colors for different parts.

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Standard Symbols

• Standard are used in preparing technical diagrams

• Can quickly describe motion & links• Illustrate the mechanisms of motion

transmission & transformation at work in a device

• Are essential so that anyone, anywhere can read the technical diagram with no confusion.

Standardized symbols

Symbols of Movements and of Forces

Tension

Compression

Shearing

Torsion

Unidirectional Translation

Bidirectional Translation

Unidirectional Rotation

Bidirectional RotationHelical Movement (Rotation and Translation)

17

Basic Lines in Technical Drawing

Standardized Symbols

Page 10

Upper Blade

Lower blade

Pivot

F

F

PaperF

A Design Plan for a pair of scissors

Bidirectional rotation

Free in rotation and fixed in translation

Shearing

The Components (parts)

Movements

Forces

A Design Plan includes the following elements:

2. The name of the parts (designation).

1. The parts represented in different colors.

A Design Plan includes the following elements:

2. The name of the parts (designation).

3. The movements carried out by the parts.

1. The parts represented in different colors.

A Design Plan:

2. Labels.

3. Movement arrows.

4. Force arrows.

5. Any guidance and links, (if necessary).

1. The parts in different colors.

22

Upper blade

Lower blade

Upper handle

Lower handle Legend of materials

Steel

Plastic

Pivot

Technical Drawing/Construction Diagram of a pair of scissors

a. The materials used;

c. Relative size of the components;

1. The pieces making up the technical object:

d. The name of the components.

A Technical Diagram contains the following:

b. The shape of the components;a. Different colors for diff parts

c. Labels

2: a. The links between the parts;b. The guidance between the parts.

1:

d. Size and extension lines

A Technical Drawing :

b. Materials used and legend;

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Exercice 1: Staple Remover

Symboles normalisés

Top Lever

Bottom Lever

Pivot Spring

Original material created by Emmanuel Fournier

Your Turn

24

Design Plan for a Staple Remover

Top Lever

Bottom Lever

Torsion Spring

Pivot

Material Legend

Steel

Plastic

Top Lever

Protector

Bottom LeverProtector

Pivot

Technical Diagram/Constuction Diagram of a Staple Remover

Assisted Exercises:

Torsion Spring

Original material created by Emmanuel Fournier

A Design Plan:

2. Labels

3. Movement arrows

4. Force arrows

5. Any guidance and links.

1. The parts in different colors.

a. Colors for diff parts;

c. Measurements

2: a. Links between the parts;b. Guidance between the parts.

1:

d. Labels

A Construction Diagram:

b. Materials used and legend;

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Manufacturing Process Sheet

• = a document describing every stage in the manufacturing of the object’s parts.

• It is usually written by the designers for the producers.• It lists all of the materials & tools to be used; indicates

the order of each operation to be performed; tells how much time it will take & how many workers needed.

• It is accompanied by another document called a flow-process grid which describes each stage in the assembly process.

• These 2 documents are like recipes for making the object.

What are Tech Objects Made of?

• Raw materials and materials• A raw material is a substance of natural origin

that undergoes a transformation.• Raw materials are transformed into materials.

Ex:Raw Material Material

Trees Planks , plywood, paper, etc.

Iron Steel beams

Sand Glass

Clay Ceramics, bricks

Bauxite Aluminum

Categories of Materials & Their Properties

Main Categories of Materials Used in Industry

• Wood• Ceramics & Glass• Metals• Stone & concrete• Polymers (plastics)• Composites (e.g. fibreglass & plastic

combined)• Textiles

Equipment

• Equipment = any object, instrument, tool or machine that is used to extract or transform raw material, or to manufacture products.

Selecting Appropriate Materials

• All technical objects are made of 1 or more materials.• Every tech object must be made of appropriate

materials if it is to work properly & last.• The selection of suitable materials is determined by the

properties of the materials & the stresses (constraints) & deformations to which they will be subjected.

• The properties of materials (ex: strength, durability, flexibility, stiffness, malleability, ductility, resistance to corrosion, conductor of heat or electricity, etc.) must be considered before selecting an appropriate one.

Technological Systems

• Is an assemblage of the following elements designed to accomplish a specific function or task:1. Inputs (energy or initial matter)2. A transformation process3. Outputs (energy or resulting matter)

Ex: A bicycle is a system:Its function is to support a person’s weight & enable the person to move.Input = the muscle force required to pedal the bike (your body uses chemical energy in food to enable you to move your muscles)Transformation Output = Kinetic energy of the bicycle

Inputs & Outputs

• In a technological system, the force applied to make the machine work constitutes one of the inputs.

• Inputs are anything that enters a system.• Outputs are everything that exits a system.• Inputs can be transformed by the system, or not.• The task that machine performs constitutes a

transformation process. The result of the process is an output.

Systems Have Subsystems

• Systems are made up of several subsystems which interact.• Every subsystem has its own function.• Each subsystem includes several parts called components.• Everything that plays a role in a technical object’s

functioning constitutes a component. If one of the components is missing, the system cannot operate properly.

Ex: The subsystems of a bicycle include:the frame, seat, wheel, transmission, steering, braking, & lighting

An Apple Peeler is a Technological System

• What are the inputs & outputs?

Inputs & Outputs of 2 SystemsApple Peeler Dishwasher

Inputs Initial Material Apples Dirty dishesWaterDishwasher detergent

Verification & Control Mechanisms

Manual adjustment of the apple

Selection of an automatic wash cycle

Energy Source Muscle force Electricity

Outputs End Material Peeled apples Clean dishes

Info given to person using machine

Red light

Waste & Residue Apple peels Waste water

Drawbacks Noise of the system operating

Basic Mechanical Functions

• A function is the role played by an object, system, subsystem or part.

• Basic mechanical functions are at the root of most technical objects. The most frequently used are the link and the guiding control.

Links

• Links are fastening units that connect 2 or more parts.

• There are 8 different possible types of links: direct or indirect; rigid or elastic; removable or non-removable; complete or partial.

Characteristics of LinksDirect Indirect

when 2 parts hold together without a linking component

when the parts require a linking component to hold them together

Rigid Flexible

when the linking component or surfaces of linked parts are rigid

when the linking component or surfaces of linked parts can be deformed. Springs & rubber are often used in flexible links.

Removable Non-removable

when the linked parts can be separated without damaging either their surfaces or the linking component (if present). Ex: Nuts & screws

when separating the linked parts damages their surfaces or the linking component.

Complete Partial

when it prevents the linked parts from moving independently of one another

when at least one part can move independently of the other parts.

• http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=1&cad=rja&ved=0CCkQFjAA&url=http%3A%2F%2Fwww.emsb.qc.ca%2Flaurenhill%2Fscience%2FLinkinginTechnical%2520Objects.pdf&ei=k3reUsOxJYzNsQSloIGYAg&usg=AFQjCNH4BI5Pa9dPDmDSTD4oio6_PQB_TA

Test Your Understanding

• What kind of links are these?– Handle on paint brush & bristles– Calculator & calculator cover– Hammer handle & head

• Write down 4 more examples of your own.

Guiding Controls

• A guiding control enables an element to move in a certain way.

• There are 3 types:1. Rotational guiding – allows the part to rotate only

(circular or oscillatory rotation).• This type of guiding control generally uses cylindrical

parts.

2. Translational guiding – allows the part to move only in a straight line (rectilinear or alternating).

• This type of guiding control generally uses parts in the shape of a rectangular prism.

Guiding Controls

3. Helical guiding – ensures the translational motion of a part while it rotates around the same axis.

What kind of guiding is it?

• Write down your own 4 examples of guiding controls, and indicate whether each is rotational, translational or helical guiding.

Machines

• A machine is any device that helps people do work.• A machine does not decrease the amount of work

that is done, but it changes the way in which the work is done.– For example, lifting a box by hand, with a ramp, or with

a crane.• All mechanical machines, no matter how complex,

are made up of any of six simple machines.

Simple Machines

• Machines that use force to make work easier.• Have no or very few moving parts.• They are found in many objects.• There are 6 types:

1. Lever2. Inclined plane3. (Screw)4. Pulley5. Wedge 6. Wheel & axle

Simple Machines Perform 3 Main Functions:

1. They transmit forces.2. They change the direction of the force.3. They modify the intensity (size) of the force.

Lever

• A simple machine used for moving or raising weights centered on a fulcrum (or turning point).

• Has 3 components:1. Fulcrum: In a lever, a moveable bar rests on a supporting point

called a fulcrum (a pivot point). 2. Load: At one end of the bar is the load, the object to be lifted or

moved.3. Force: A force must be applied to the other end of the bar.

• The portion of the bar between the fulcrum & the force is the lever arm.

• The portion of the bar between the fulcrum & the load is called the load arm.

Examples of levers:

– Hockey stick– Baseball bat– Your arm– Door– Laptop lid

3 Types of Levers

• The positions of the lever’s components can be changed.

• There are 3 types of levers:1. First class2. Second class3. Third class

First Class Levers

• The fulcrum is in the middle & the load & force (effort) are on either side.

• Ex: see-saw, crowbar, scissors

Second Class Lever

• The fulcrum is at the end. With the load in the middle.

• Ex: wheelbarrow, bottle opener, nutcracker

Third Class Lever

• The fulcrum is at the end, but the force (effort) is in the middle.

• Ex: Tweezers, broom, shovel, fishing rod

Inclined Plane

• Is a flat surface that is higher on one end.• Make work of moving things easier• Ex: ramp, hill, slide, doorstop

Screw

• Is an inclined plane wrapped around a shaft or cylinder.

• Allows the screw to move itself when rotated.• Ex: jar lid, light bulb, clamp, jack, wrench, key,

rings, spiral stair case

Wedge

• 2 inclined planes joined back to back.• Are used to split things.• Ex: chisel, fork, nails, ice scraper, blade of an

axe or a knife

Wheel & Axle

• Is a rod that goes through a wheel which allows the wheel to turn.

• Gears are a form of wheels & axle• Ex: Screw driver, roller skates, steering wheel,

door knob, electric fan

Pulley

• Is a wheel & axle with a groove around the outside.

• Needs a rope, chain, or belt around the groove to make it work.

• Ex: top of flag pole, clothes line, on sailboat, blinds, crane

There are 2 Types of Pulleys:

1. Fixed Pulley: is attached to something that holds it steady. It makes work easier by changing the direction of the work.

2. Moveable Pulley: One end of the rope is fixed & the load is attached to the wheel.

Energy Transformation

• In technology, we define energy as a system’s capacity to do work, especially to make objects move.

• There are many forms of energy, and it is possible to change from one form to another, i.e., to transform energy or convert it.

There Are Many Forms of Energy

• There are many sources of energy all around you, & you use many to fulfill your needs. Write down as many forms of energy that you can think of.

There Are Many Forms of Energy:

• Potential Energy = energy an object possesses because of its position above a surface.– a ball you hold has potential energy. If you let it

fall, its potential energy transforms into kinetic energy, & it will fall to the ground.

– Potential energy is a specific form of mechanical energy.

• Elastic energy = energy an object possesses when its shape is changed through stretching or compression.– Ex: stretched elastic or compressed spring store

elastic energy– When a force ceases to be applied to them, they

assume their original shapes– It is a specific form of potential energy.

• Kinetic Energy = the energy of objects in motion.– Ex: a moving car or bicycle, a tossed ball– It is a specific form of mechanical energy.

• Radiant Energy = energy that enables you to see objects. When it hits your eyes, it triggers production of signals which travel to your brain & tells you what you are seeing.– Ex: light bulb, sun, fire– Radiant or radiation energy is a specific form of

electromagnetic energy.

• Electrical energy = energy resulting from the ordered movement of electrons from one atom to another.– Ex: Makes machines like TVs & computers work,

used to power lighting & heating systems

• Magnetic energy = the form of energy that magnets possess due to their positions relative to each other.– Like poles repel each other, opposites attract.– It is a form of potential energy because it depends

on the position of the object.

• Thermal Energy = energy resulting from the random motion of all particles in a substance.– It is present in all objects. When an object has a

lot of thermal energy, the object is hot; if it contains very little, it is cold.

• Chemical Energy = energy stored in molecular bonds. It is released during a chemical reaction.– Ex: Chemical energy in gas turns car engines;

chemical energy in food is used by your body to do things like move.

• Nuclear Energy = energy stored in nuclei of atoms. Special techniques are required to release the nuclear energy contained in radioactive substances, such as uranium.

• Acoustic Energy (sound energy) = energy produced when matter vibrates. It makes the ossicles (small bones) in your ears move, which transmit signals to your brain to tell you what you are hearing.

Mechanisms That Transform Energy

• Law of conservation of energy