DESIGN INSTALLATION OF ART AND INDUSTRIAL DESIGN CLOCK FOR TIME CONSCIOUSNESS
ABSTRACT
This project work is about design installation of Art and Industrial Clock for time consciousness. The objective of the study is to achieve a wall clock with Art and Industrial Design (AID) that will mark every single second of the time to the department of Art and Industrial Design and for student to know their time of lecture and leisure time in their day to day activities in school. Quality materials and equipment was used to construct the wall clock. The result of the study has shown that time is very important and will help students to be time conscious. It was recommended that project of this nature should be given total attention by the designated student and proper supervision by the project supervisor to ensure accuracy in the framework and finishing and Project defence should be standardize defence and exhibition should sect the same day so that all graduating student will have room to discuss their project work one after the other before internal and external supervisor.
CHAPTER ONE
INTRODUCTION
1.1 Background of the study
A clock is an instrument to indicate, keep, and co-ordinate time. The word clock is derived from (via Dutch, Northern French, and Medieval Latin) from the Celtic words clagan and clocca meaning “bell“. In general usage today a “clock” refers to any device for measuring and displaying the time. Watches and other timepieces that can be carried on one’s person are often distinguished from clocks (Kak, 2003).
The clock is one of the oldest human inventions, meeting the need to consistently measure intervals of time shorter than the natural units: the day, the lunar month, and the year. Devices operating on several physical processes have been used over the millennia. A sundial shows the time by displaying the position of a shadow on a flat surface. There are a range of duration timers, a well-known example being the hourglass. Water clocks, along with the sundials, are possibly the oldest time-measuring instruments. A major advance occurred in Europe around 1300 with the invention of the escapement, which allowed construction of the first mechanical clocks, which used oscillating timekeepers like balance wheels. Spring-driven clocks appeared during the 15th century. During the 15th and 16th centuries, clock making flourished. The next development in accuracy occurred after 1656 with the invention of the pendulum clock. A major stimulus to improving the accuracy and reliability of clocks was the importance of precise time-keeping for navigation. The electric clock was patented in 1840. The development of electronics in the 20th century led to clocks with no clockwork parts at all (Needham, 2000)
Zea (2002), stated that timekeeping element in every modern clock is a harmonic oscillator, a physical object (resonator) that vibrates or oscillates repetitively at a precisely constant frequency. This object can be a pendulum, a tuning fork, a quartz crystal, or the vibration of electrons in atoms as they emit microwaves. Analog clocks usually indicate time using angles. Digital clocks display a numeric representation of time. Two numeric display formats are commonly used on digital clocks: 24-hour notation and 12-hour notation. Most digital clocks use electronic mechanisms and Liquid Crystal Display (LCD), Light Emitting Diode (LED), or Video Frequency Unit (VFD) displays. For convenience, distance, telephony or blindness, auditory clocks present the time as sounds. There are also clocks for the blind that have displays that can be read by using the sense of touch. Some of these are similar to normal analog displays, but are constructed so the hands can be felt without damaging them. The evolution of the technology of clocks continues today. The study of timekeeping is known as horology.
1.2 Time-measuring devices
Sundials
When the Sun is shining, its apparent position in the sky moves during a day, reflecting the rotation of the Earth. Shadows cast by stationary objects move correspondingly, so their positions can be used to indicate the time of day. A sundial shows the time by displaying the position of a shadow on a (usually) flat surface, which has markings that correspond to the hours. Sundials can be horizontal, vertical, or in other orientations. Sundials were widely used in ancient times. With the knowledge of latitude, a well-constructed sundial can measure local solar time with reasonable accuracy, within a minute or two. Sundials continued to be used to monitor the performance of clocks until the modern era. However, practical limitations, such as that sundials work only when the Sun shines, and never during the night, encouraged the use of other techniques for measuring and displaying time.
1.3 Aim
To achieve a wall clock with Art and Industrial Design (AID) that will mark every single second of the time to the department of Art and Industrial Design
1.4 Objective
i. To assist students to be time conscious.
ii. For students to learn how to work with time.
iii. To rouse in the students the sense of time management
iv. For student to be time discipline.
v. For student to know there time of lecture and leisure time in there day to day activities in school.
1.5 Purposes of clock
Clocks are in homes, offices and many other places; smaller ones (watches) are carried on the wrist or in a pocket; larger ones are in public places, e.g. a railway station or church. A small clock is often shown in a corner of computer displays, mobile phones and many MP3 players.
The primary purpose of a clock is to display the time. Clocks may also have the facility to make a loud alert signal at a specified time, typically to waken a sleeper at a preset time; they are referred to as alarm clocks. The alarm may start at a low volume and become louder, or have the facility to be switched off for a few minutes then resume. Alarm clocks with visible indicators are sometimes used to indicate to children too young to read the time that the time for sleep has finished; they are sometimes called training clocks.
A clock mechanism may be used to control a device according to time, e.g. a central heating system, a Video Cassette Recorder (VCR), or a time bomb (see: digital counter). Such mechanisms are usually called timers. Clock mechanisms are also used to drive devices such as solar trackers and astronomical telescopes, which have to turn at accurately controlled speeds to counteract the rotation of the Earth.
Most digital computers depend on an internal signal at constant frequency to synchronize processing; this is referred to as a clock signal. (A few research projects are developing Central Processing Unit (CPU) based on asynchronous circuits.) Some equipment, including computers, also maintains time and date for use as required; this is referred to as time-of-day clock, and is distinct from the system clock signal, although possibly based on counting its cycles.
1.6 How clocks work
Rossum and Gerhand (1996), speculated that, the invention of the mechanical clock in the 13th century initiated a change in timekeeping methods from continuous processes, such as the motion of the gnomon‘s shadow on a sundial or the flow of liquid in a water clock, to periodic oscillatory processes, such as the swing of a pendulum or the vibration of a quartz crystal, which had the potential for more accuracy. All modern clocks use oscillation.
Although the methods they use vary, all oscillating clocks, mechanical and digital and atomic, work similarly and can be divided into analogous parts. They consist of an object that repeats the same motion over and over again, an oscillator, with a precisely constant time interval between each repetition, or ‘beat’. Attached to the oscillator is a controller device, which sustains the oscillator’s motion by replacing the energy it loses to friction, and converts its oscillations into a series of pulses. The pulses are then counted by some type of counter, and the number of counts is converted into convenient units, usually seconds, minutes, hours, etc. Finally some kind of indicator displays the result in human readable form.
1.7 Power source
This provides power to keep the clock going.
- In mechanical clocks, the power source is typically either a weight suspended from a cord or chain wrapped around a pulley, sprocket or drum; or a spiral spring called a mainspring. Mechanical clocks must be wound periodically, usually by turning a knob or key or by pulling on the free end of the chain, to store energy in the weight or spring to keep the clock running.
- In electric clocks, the power source is either a battery or the AC power line. In clocks that use AC power, a small backup battery is often included to keep the clock running if it is unplugged temporarily from the wall or during a power outage. Battery powered analog wall clocks are available that operate over 15 years between battery changes (Rossum and Gerhand 1996).
1.8 Oscillator
The timekeeping element in every modern clock is a harmonic oscillator, a physical object (resonator) that vibrates or oscillates repetitively at a precisely constant frequency.
- In mechanical clocks, this is either a pendulum or a balance wheel.
- In some early electronic clocks and watches such as the Accutron, it is a tuning fork.
- In quartz clocks and watches, it is a quartz crystal.
- In atomic clocks, it is the vibration of electrons in atoms as they emit microwaves.
- In early mechanical clocks before 1657, it was a crude balance wheel or foliot which was not a harmonic oscillator because it lacked a balance spring. As a result, they were very inaccurate, with errors of perhaps an hour a day.
The advantage of a harmonic oscillator over other forms of oscillator is that it employs resonance to vibrate at a precise natural resonant frequency or ‘beat’ dependent only on its physical characteristics, and resists vibrating at other rates. The possible precision achievable by a harmonic oscillator is measured by a parameter called its Q, or quality factor, which increases (other things being equal) with its resonant frequency. This is why there has been a long term trend toward higher frequency oscillators in clocks. Balance wheels and pendulums always include a means of adjusting the rate of the timepiece. Quartz timepieces sometimes include a rate screw that adjusts a capacitor for that purpose. Atomic clocks are primary standards, and their rate cannot be adjusted.
1.9 Controller
This has the dual function of keeping the oscillator running by giving it ‘pushes’ to replace the energy lost to friction, and converting its vibrations into a series of pulses that serve to measure the time.
- In mechanical clocks, this is the escapement, which gives precise pushes to the swinging pendulum or balance wheel, and releases one gear tooth of the escape wheel at each swing, allowing all the clock’s wheels to move forward a fixed amount with each swing.
- In electronic clocks this is an electronic oscillator circuit that gives the vibrating quartz crystal or tuning fork tiny ‘pushes’, and generates a series of electrical pulses, one for each vibration of the crystal, which is called the clock signal.
- In atomic clocks the controller is an evacuated microwave cavity attached to a microwave oscillator controlled by a microprocessor. A thin gas of cesium atoms is released into the cavity where they are exposed to microwaves. A laser measures how many atoms have absorbed the microwaves, and an electronic feedback control system called a phase-locked loop tunes the microwave oscillator until it is at the exact frequency that causes the atoms to vibrate and absorb the microwaves. Then the microwave signal is divided by digital counters to become the clock signal.
1.10 Counter chain
This counts the pulses and adds them up to get traditional time units of seconds, minutes, hours, etc. It usually has a provision for setting the clock by manually entering the correct time into the counter.
- In mechanical clocks this is done mechanically by a gear train, known as the wheel train. The gear train also has a second function; to transmit mechanical power from the power source to run the oscillator. There is a friction coupling called the ‘cannon pinion’ between the gears driving the hands and the rest of the clock, allowing the hands to be turned to set the time.
- In digital clocks a series of integrated circuit counters or dividers add the pulses up digitally, using binary logic. Often pushbuttons on the case allow the hour and minute counters to be incremented and decremented to set the time.
1.11 Indicator
This displays the count of seconds, minutes, hours, etc. in a human readable form.
- The earliest mechanical clocks in the 13th century didn’t have a visual indicator and signalled the time audibly by striking bells. Many clocks to this day are striking clocks which strike the hour.
- Analog clocks display time with an analog clock face, which consists of a round dial with the numbers 1 through 12, the hours in the day, around the outside. The hours are indicated with an hour hand, which makes two revolutions in a day, while the minutes are indicated by a minute hand, which makes one revolution per hour. In mechanical clocks a gear train drives the hands; in electronic clocks the circuit produces pulses every second which drive a stepper motor and gear train, which move the hands.
- Digital clocks display the time in periodically changing digits on a digital display. A common misconception is that a digital clock is more accurate than an analog wall clock, but the indicator type is separate and apart from the accuracy of the timing source.
- Talking clocks and the speaking clock services provided by telephone companies speak the time audibly, using either recorded or digitally synthesized voices.
1.12 Definition of terms
Devices: An object or piece of equipment that have been design to perform a particular job.
Automata: a machine that contains its own power source and can perform a complicated series of actions, including responses to external stimuli, without human intervention.
Escapement: in a clock or watch, a mechanism that permits motion in only one direction, allowing power from a spring or falling weight to turn gears connected to the hands.
Astronomer: A scientist who study sun, moon, star, planet etc.
Canonical: Conforming to accepted principles or standard practice
Canonical hour: in the Roman Catholic Church, one of the daily prayer times when specific prayers are said. These times are the matins with lauds, prime, terce, sext, nones, vespers, and compline.
Oscillators: A piece of equipment that produce change at regular interval of electric current.
Synchronous: Happening or existing at the same time.
AID: Art and Industrial Design
VCR: Video Cassette Recorder (a machine used to play video or record).
CPU: Central Processing Unit (a part of computer that controls all the parts of the system).
Clock: a freestanding device that measures and records time, which it displays by a pointer on a dial or by a digital readout
Sundials: A device used outdoors especially in the past, for telling the time when the sun is shining or a pointed piece of metal throws a shadow on a flat surface that is marked with the hours like a clock and shadow moves around as the sun moves across the sky.
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