INTRODUCTION TO TECHNOLOGY

INTRODUCTION TO TECHNOLOGY

I. WHAT IS TECHNOLOGY?

A. DEFINITION OF TECHNOLOGY

Technology is the technical means people use to improve their surroundings. It is also a knowledge of using tools and machines to do tasks efficiently. We use technology to control the world in which we live. Technology is people using knowledge, tools, and systems to make their lives easier and better. People use technology to improve their ability to do work. Through technology, people communicate better. Technology allows them to make more and better products. Our buildings are better through the use of technology. We travel in more comfort and speed as a result of technology. Yes, technology is everywhere and can make life better.

B. SCIENCE AND TECHNOLOGY

Often the terms, technology and science, are confused. Technology is said to be "applied science". This is not true. Science deals with the natural world. Technology is the study of the natural laws which govern the universe. Science tells us that objects will fall to the earth (law of gravity). Science explains why only certain plants are found on the Mojave Desert (plant ecology). Science tells us that steel exposed to oxygen will rust (chemistry). Science tells us that cross-pollinating plants will produce predictable results (biology). Science tells us that oil is most likely found near certain rock formation (geology). On the other hand, technology deals with the human-made world. It is the study of ways people develop and use technical means - tools and machines. It tells us how to control the natural and human-made world. It is the study of the ways people use these technical means to transport, manufacture, construct, and communicate. This is not to say science and technology are unrelated. Science deals with "understanding" while technology deals with "doing". Science helps us know how to do something efficiently.

C. TECHNOLOGY THROUGHOUT HISTORY

1. THE STONE AGE

Stone Age, the time, early in the development of human cultures, before the use of metals, when tools and weapons were made of stone. The dates of the Stone Age vary considerably for different parts of the world. In Europe, Asia, and Africa it began about 2 million years ago. In the most advanced parts of the Middle East and Southeast Asia it ended about 6000 bc, but it lingered until 4000 bc or later in Europe, the rest of Asia, and Africa. The Stone Age in the Americas began when human beings first arrived in the New World, some 30,000 years ago, and ended in some areas about 2500 bc at the earliest. Throughout the immense time span of the Stone Age, vast changes occurred in climate and in other conditions affecting human culture. Humans themselves evolved into their modern form during the latter part of it. The Stone Age has been divided accordingly into three periods: the Paleolithic, Mesolithic, and Neolithic.

2. THE BRONZE AGE

Bronze Age, the time in the development of any human culture, before the introduction of iron, when most tools and weapons were made of bronze. Chronologically, the term is of strictly local value, for bronze came into use, and was again replaced by iron, at different times in different parts of the world. It generally succeeds a culture's Copper Age.

3. THE IRON AGE

Iron Age, marks the period of development of TECHNOLOGY, when the working of iron came into general use, replacing bronze as the basic material for implements and weapons. It is the last stage of the archaelogical sequence known as the three-age system (Stone Age, Bronze Age, & Iron Age). Chronologically, the tem is only of local value because iron took the place of bronze at different times in different cultures.

4. THE INDUSTRIAL REVOLUTION

During certain periods in history, innovations in technology have grown at such a rapid pace that they have produced what have become known as industrial revolutions. The term INDUSTRIAL REVOLUTION originally referred to the developments that transformed Great Britain, between 1750 and 1830, from a largely rural population making a living almost entirely from agriculture to a town-centered society engaged increasingly in factory manufacture. Other European nations underwent the same process soon thereafter, followed by others during the 19th century, and still others (such as Russia and Japan) in the the first half of the 20th century. In some countries this transformation is only now taking place or still lies in the future.

5. THE 20TH CENTURY

A. Introduction

Technology is rapidly changing our world. It is bringing us services beyond our grandparent's wildest dreams. It seems that with each year the pace of change quickens. Each new process or invention makes still other advances possible. Such 19th and 20th century inventions as the telephone, the phonograph, the wireless radio, the motion picture, the automobile, and the airplane served only to add to the nearly universal respect that society in general felt for technology. With the development of assembly-line mass production of automobiles and household appliances, and the building of ever taller skyscrapers, acceptance of innovations became not only a fact of everyday life but also a way of life in itself. Society was being rapidly transformed by increased mobility, rapid communication, and a deluge of available information from mass media.

B. TECHNICAL EDUCATION

One of the several reasons why the United States became a technological leader in the 20th century was its development of an advanced system of technical education. Mechanical arts schools began in Philadelphia in the 18th century, and by the end of the 19th century they had spread to every major American city. In the 20th century, a state-based system of vocational education provided training in basic technical skills. Between 1862 and 1890, engineering and agricultural colleges in every state were funded by a federal program known as the Morrill Land Grant. In addition, since the early 1920s, every rural county in the nation has had a Federal Extension Service office that is responsible for disseminating information to farmers on new technologies and research.

C. REASSESSMENTS OF TECHNOLOGY

World War I and the Great Depression forced a sobering reassessment of this rapid technological explosion. The development of submarines, machine guns, battleships, and chemical warfare made increasingly clear the destructive side of technological change. Then, with World War II, came the development of the weapon that has since become a general threat to life on earth: the atomic bomb. Although national leaders often speak of the peaceful uses of nuclear energy, nuclear power can never be discussed without referring to its dangers as well. Another technological outgrowth of World War II, the development of computers and transistors and the accompanying trend toward miniaturization, is having equally profound effects on society as well. The possibilities it offers are enormous, but so are the possibilities for invasion of privacy and for work-force displacement by automated systems.

D. OUTLOOK

Twentieth-century technology spread from Europe and the U.S. to other major nations such as Japan and the Soviet Union. It has not, however, pervaded all the countries of the world, by any means. Some so-called developing nations have never experienced the factory system and other institutions of industrialization. The leaders of such countries tend to feel that the acquisition of modern weapons and new technology will provide them with power and prestige. Technology has always been a major means for creating new physical and human environments. It is possible to ask today whether technology will also destroy the global civilization that human beings have created.

II. TECHNOLOGICAL SYSTEMS

A. DEFINITION OF A TECHNOLOGICAL SYSTEM

We often use the word system. We talk of our digestive system or the fuel system of a car. We read of computer and communication systems. All systems have some basic parts which include the following:

INPUTS - THE RESOURCES USED BY THE SYSTEM

1. INPUTS TO TECHNOLOGICAL SYSTEMS

There are six major inputs used by technological systems. These are:

People

Natural Resources (materials)

Capital (tools and machines)

Finance (money)

Knowledge (information)

Energy

Each of these six inputs are essential for technological systems. They are all used and must be present.

PROCESSES - THE ACTIONS TAKEN TO USE THE INPUTS

1. PROCESSES OF TECHNOLOGY

Technological systems use two major types of processes. These are:

Production processes

Management processes

These two processes are united. They work together to convert the resources into the desired outputs.

OUTPUTS - THE RESULT OF THE SYSTEM

1. OUTPUTS OF TECHNOLOGICAL SYSTEMS

Almost all technological systems have two types of outputs:

A. The first is the one for which the system was designed. These outputs may be a manufactured product, constructed work, communicated message, or transported person. Each of these outputs are seen as good. They are what people want and need to live better.

B. However, most technological systems produce other outputs. These are in addition to the desired outputs. These other outputs may be of two kinds:

Scrap and waste

Pollution

FEEDBACK - ADJUSTMENTS MADE TO THE PROCESSES TO IMPROVE THE OUTPUTS

GOALS — REASON FOR THE SYSTEM

1. Custom manufacturing

Custom manufacturing is the oldest system. In early history, one person made the entire product. That person had all the skill needed to process the materials into products. Most products of colonial times were custom made. The silversmith made silver bowls and candle holders. The cobbler made shoes. The weaver made cloth. The tailor made clothing. This early machine allowed a worker to custom manufacture a gun stock. Later, custom manufacturing systems were used to make very special products. These products were designed for the customer. Only a few products were built to fill a need. Today, spacecraft, ships, some cabinets and furniture, and clothing for special needs are custom manufactured. Sometimes, many people will work on the same product.

2. Intermittent and batch manufacturing

As the nation grew, custom manufacturing could not meet demand. There were a great many more people. They wanted more products. The skilled craft worker could not produce products fast enough. Small factories were started. The products were made in small batches. Maybe a dozen or more candle sticks were made at a time. This system was called intermittent manufacture. Intermittent manufacturing is widely used today. In this system the parts for a product travel in a lot or batch. For example, suppose 100 bird houses are needed. One part is the front. First, workers select lumber to make the fronts. Next, they move the boards to a saw. Here 100 bird house fronts are cut to length. These parts are put in a tray. The tray moves to a drill press. Workers drill the entry hole for the bird in all 100 parts. The tray of parts travels to another drill press. Perch holes are drilled in each piece. The parts finally move to another saw. Here the roof peak is cut on all 100 parts. Do you see that the parts moved from operation to operation in a batch?

3. Continuous manufacturing

When many products are needed, continuous manufacture is generally used. The parts move down a manufacturing line. At each station on the line a worker completes a specific operation. Workers at each station are trained to do the job quickly. The product takes shape as it moves along the line. Completed parts flow to an assembly line. Here the parts are put together to form the finished product.

4. Flexible manufacturing

Each of these systems is in wide use today. Each has its place and serves a specific purpose.

2. PEOPLE-TO-MACHINE COMMUNICATION

People communicate to machines daily. We set controls which "tell" the machine how to operate. We set the thermostat to communicate the room temperature we want to a heating/cooling system. We set a speed control system in a car to communicate the speed we want to travel. Also, we write computer programs to tell the computer what to do. We can tell it to print letters, calculate costs, or perform hundreds of other acts.

3. MACHINE-TO-PEOPLE COMMUNICATION

Directly related to people-to-machine communication is machine-to-people communication. The machine we communicated to through switches and dials responds. It will present us with meter readings, flashing lights, or alarms. Pilots have many machine-to-people communication systems on the aircraft flight deck. Lights tell them if the engines are running properly. Alarms sound as the plane approaches stall speed. Video screens display the information gathered by the radar system. In our automobiles, gauges and lights are also used to communicate. The fuel gauge tells the driver when to buy more gasoline. The oil light warns the operator of low oil pressure. A blue light tells the driver that the headlights are on high-beam.

4. MACHINE-TO-MACHINE COMMUNICATION

The most recent communication systems have machines providing information to machines. Computer-aided design (CAD) systems, help people design parts. They do drafting. The system can then direct machines to produce the part. Computer-aided manufacturing (CAM) uses computers to directly control machine operations. The computer can direct the machine to run at specific speeds. It can set material feed rates. It can cause the machine to change cutting tools. All this occurs without human action. Even more complex systems totally merge the design and manufacturing activities. These systems are called computer- integrated manufacturing (CIM). These are but a few examples of machines communicating to machine.

E. TRANSPORTATION SYSTEMS

Transportation is the movement of people and goods from one place to another. Transportation technology is built around the vehicle. This vehicle must be designed to suit the purpose. Every vehicle must have:

1. A Structure — VEHICULAR STRUCTURES

Vehicles are movable structures. They hold not only people and goods but the means of moving the structure from one place to another along a path. The structure also provides a rigid framework to support other systems. You are accustomed to riding vehicles. Maybe you had a tricycle when you were a small child. It had all the necessary parts of a vehicle. It was a complete system. The tricycle had a frame. The frame supported all the other parts. The frame was the structure of the tricycle. Like the tricycle, any transportation vehicle has a framework that supports all of the vehicle's parts The framework has a covering.

2. A means of Propulsion — PROPULSION SYSTEMS

This means a power source to move the vehicle. Usually, this is some kind of engine. Heat engines are the most common form of power for moving vehicles. We know them as:

A. Gasoline engines

B. Diesel engines

C. Jet engines

D. Gas turbines

E. Rocket engines

3. A means of Transmission — TRANSMISSION OF POWER

A power source, or propulsion unit must have a way to move power to do work. This is called transmission. It means to move from one spot to another. Power can be transmitted by:

Belts or chains - A bicycle chain moves power from the bicycle pedals to the rear wheel.

Gears - These are notched wheels that mesh (fit together). One gear will drive another.

Shafts - A shaft carries an engine's turning action to the drive wheels.

Fluids - Compressed air or liquid can lift or move objects. For example, pressure on the water makes water fountains work in your school.

Electricity or electromechanical

means - Electricity can be transmitted through a conductor such as a wire. The electricity can then drive a motor. The motor causes the force or motion.

A robot is an example of a mechanism that can be controlled and moved by several methods. It may use electromechanical devices. It may have gears and shafts. Chains may be used to make some movements.

To transmit its power to move a vehicle, the propulsion unit must be attached to the vehicle. The jet engine moves forward from the greater pressure of gases on the forward end of the engine. This force is transferred through the engine. Because the engine is attached to the frame of the aircraft, the aircraft moves too. However, the motion of many heat engines is rotary (circular). Another mechanism called a transmission must transfer the rotary motion to the wheels. In the simplest transmissions, two discs are used. One is attached to the crankshaft of the engine. It spins with the crankshaft. The other is attached to the drive shaft and drive wheels. When power is needed to drive the vehicle, springs press the two discs together. The one attached to the engine is already spinning. It causes the other to spin also. Gears at the other end of the drive shaft transmit the power to the wheels. They are connected to the wheels by long shafts.

4. A Guidance System — GUIDANCE SYSTEMS

Guidance systems are not part of the vehicle. They provide information to the vehicle's operator. Aircraft receive instructions from a flight controller. This person directs the aircraft into and away from the airport. The controller tells the pilot when to take off or land, what course to follow, and what height to fly at. Towers in foreground hold radar equipment and television cameras. They help control vessels on land. Railroads have signals along the right-of- way. Highways traffic gets information from stop signs, stop lights, and other roadside signs.

5. Control Systems — CONTROL SYSTEMS

The operator must be able to stop, start, speed up, slow down, and turn the vehicle. This is arranged through systems of control. They vary somewhat from vehicle to vehicle:

A. Braking system. Trains and highway vehicles and airplanes have wheel brakes. Air or hydraulic pressure pushes pads or blocks against the wheels. Friction produces drag on the wheels to slow or stop the vehicle. Airplanes also have wing flaps. They produce air drag and help slow the plane. Ships are slowed or stopped by reversing the propellers. Aircraft engines are also used to slow the plane after landing.

B. The amount of power needed to move a vehicle will vary. The operator must be able to control the amount of power. Acceleration and deceleration controls will vary speed by controlling the amount of fuel delivered to the engine.

C. Vehicles also must have directional control. Steerable land vehicles have wheels that turn left and right. Ships and airplanes have rudders for left and right movement. Airplanes also control up and down movement with an elevator. It is part of the tail assembly.

D. Miscellaneous controls. These include switches to turn on lights, windshield wipers, windshield washers, defrosters, heaters, and radios. These are usually simply "on-off" electrical switches. They control electrical current to the devices.

6. Measurement Devices — MEASUREMENT DEVICES

Measurement devices monitor or check that the vehicle is operating properly. The driver must receive information about the operation of the vehicle's systems. This information is provided by dials and gauges:

A fuel gauge tells the operator how much fuel is left.

Electrical gauges indicate whether the vehicle's alternator is generating enough electricity. It is important that the battery does not discharge. A discharged battery is not able to start the vehicle.

Speed indicators measure how fast a vehicle is traveling. An odometer measures distance the vehicle has traveled. It alerts the driver to have the vehicle serviced. It also gives information about distance traveled during a trip.

Temperature gauges register the temperature of the engine coolant. They alert the driver of overheating problems so proper repairs or service can be performed before the engine is damaged.

III. THE DESIGN PROCESS

A. THE PROBLEM

The process of designing begins when there is a need. Wherever there are people there are problems needing solutions. In some cases the designer may have to invent a product. An example might be a game for blind persons. At other times the designer may change an existing design. (If the handle of a pot becomes too hot to touch, it must be redesigned.) Designers also improve existing products. They make the product work even better. Could the chair in the waiting room of a bus or train station be altered so that waiting seems shorter?

B. THE DESIGN BRIEF

A design brief should describe simply and clearly what is to be designed. The design brief cannot be vague. Some examples of problems and design briefs are listed below:

PROBLEM: Blind people cannot play many of the indoor games available to sighted people.

DESIGN BRIEF: Design a game of dominoes that can be played by blind people.

PROBLEM: The handle of a pot becomes too hot to hold when the pot is heated.

DESIGN BRIEF: Design a handle that remains cool when the pot is heated.

PROBLEM: Waiting time in a bus or train station seems too long. There is nothing to do.

DESIGN BRIEF: Modify the seats so that a small television can be attached.

C. INVESTIGATION

Writing a clearly stated design brief is just one step. Now you must write down all the information you think you may need. Some think to consider are the following:

1. FUNCTION: A functional object must solve the problem described in the design brief. The basic question to ask is : "What, exactly, is the use of the article?"

2. APPEARANCE: How will the object look? The shape, color, and texture should make the object attractive.

3. MATERIALS: What materials are available to you? You should think about the cost of these materials. Are they affordable? Do they have the right physical properties, such as strength, rigidity, color, and durability?

4. CONSTRUCTION: Will it be hard to make? Consider what methods you will need to cut, shape, form, join, and finish the material.

5. SAFETY: The object you design must be safe to use. It should not cause accidents.

D. DEVELOPING ALTERNATIVE SOLUTIONS

You should produce a number of solutions. It is very important that you write or draw every idea on paper as it occurs to you. This will help you remember and describe them more clearly. It is also easier to discuss them with other people if you have a drawing. These first sketches do not have to be very detailed or accurate. They should be made quickly. The important thing is to record all your ideas. Do not be critical. Try to think of lots of ideas, even some wild ones. The more ideas you have, the more likely you are to end up with a good solution.

E. CHOOSING A SOLUTION

You may find that you like several of the solutions. Eventually, you must choose one. Usually, careful comparison with the original design brief will help you to select the best. You must also consider:

Now you can choose what to do next. You can make a model and later a prototype, or, you can go directly to making a prototype.

F. MODELS AND PROTOTYPES

A model is a full-size or small-scale simulation of an object. Architects, engineers, and most designers use models. Models are one more step in communicating an idea. It is far easier to understand an idea when seen in three-dimensional form. A scale model is used when designing objects that are very large. A prototype is the first working version of the designer's solution. It is generally full-size and often handmade. For a simple object such as a pencil holder, the designer probably would not make a model. He or she may go directly to a prototype.

G. TESTING AND EVALUATING

Testing and evaluating answers three basic questions:

1. Does it work?

2. Does it meet the design brief?

3. Will modifications improve the solution?

The question "does it work?" is basic to good design. It has tob e answered. This same quesiton would be asked by an engineer designing a bridge, by the designer of a subway car, or by an architect planning a new school. If you were to make a mistake in the final design of the pencil holder what would happen? The result might simply be unattractive. At worst, the holder would not work well. Not so if a designer makes mistakes in a car's seat belt design. Someone's life may be in danger!

H. MANUFACTURING

The company is satisfied with the design. It knows that it is marketable (will sell). It must decide how many to make. Products may be mass-produced in low volume or high volume. Specialized medical equipment is produced in hundreds. Other products, for example nuts and bolts, are produced in large volume. Millions may be made. The task of making the product is divided into jobs. Each worker trains to do one job. As workers complete their special jobs, the product takes shape. Mass production saves time. Since workers train to do a particular job, each becomes skilled in that job. Also, automatic equipment does such things as: