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Assembly Line Astrology and Astronomy Mechanical clocks Sextant Huntsman steel Precision in manufacturing The lathe Standard interchangeable parts Longitude An ... – PowerPoint PPT presentation

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Title: Assembly%20Line


1
Assembly Line
  • Astrology and Astronomy
  • Mechanical clocks
  • Sextant
  • Huntsman steel
  • Precision in manufacturing
  • The lathe
  • Standard interchangeable parts

2
600-539 B.C.
  • Astronomers divided the sky into twelve
    constellations (clusters of stars), 30 degrees
    apart in 360 degrees.
  • This marked the beginning of astrology.
  • Sexagesimal s

3
760AD- Caliph, Al Mansur became ill
  • Seemingly cured through assessment of star
    positions and Gundeshapur medicine.
  • Lead to increased study of star positions and
    improvement of the Astrolabe.

4
Translated Arab into Latin
  • The Almagest (Arab translation of Ptolemys star
    table) and many other texts were translated into
    Latin during the 12th century.

5
1276 Alfonsine Table Is Standard Star Reference
  • By 1276 the king of Castile ordered a compilation
    of star tables called the Alfonsine Tables. Later
    these star positions were worked out for Paris
    and other places.

6
When Is It Time to Pray
  • St. Benedict specified certain activities at
    certain times of day and night which led to the
    water alarm clock.
  • 11th Century Water alarm clock (Clepsydra)
    developed.

7
A Modified Clepsydra
First clocks were water powered back in
Alexandria 2250 BP.
8
First All Mechanical Clock
Verge and foliot escapement 1275 AD
9
1275AD -Verge and Foliot Escapement
  • This all mechanical clock was widely used by
    priests and astronomers.
  • By 1400 AD clocks were telling people when to
    work. It increased productivity.
  • Accurate to within 15 minutes per day.

Verge and Foliot clock in action
The great clock of Rouen, Fr.
10
A Venetian 24hr Clock
11
AM and PM
  • AM comes from Latin for ante meridian,which
    means before noon.
  • PM comes from Latin for post meridian, which
    mean after noon.
  • The 12 clock chimes are easier to understand.

12
1450 AD portable clocks
  • Driven by a carbon steel spring and controlled by
    the Fusee
  • Carbon steel was made by heating carbon and iron
    together, then hammering off the hard carbonized
    steel.

Fusee
Spring driven barrel
Blister Steel
13
1608- LippersheysLooker
  • A telescope intended for military purposes but
    led to Galileo to confirm Copernicus that the
    Earth is not the center of the universe.

14
Achromatic Lens
  • Early telescope lenses bent different colors
    differently resulting in a blurry image.
  • Dollonds composite lens was made of Flint and
    Crown glass giving focal point of white light.
    Result was a sharp image.

Severe chromatic aberration
15
The Pendulum Clock
  • Galileos experimentation of pendulums led to
    Huygens, pendulum clock.
  • First ones only accurate to 10min/day.
  • By 1725 engineered escapements allowed accuracy
    within 1 second per day. Nevertheless, this clock
    was useless at sea.

16
Modern Escapements
  • A British clockmaker George Daniels invented the
    co-axial escapement first used by Omega SA in
    1999.
  • The design uses radial friction instead of
    sliding friction. Resulting in longer life and
    improved accuracy.
  • See the Daniels co-axial escapement in action

17
Verge and Pendulum Escapement
How it works
18
1731 John Hadleys sextant
  • A precise astrolab, capable of measuring angle
    between two objects such as the sun and horizon.
  • The first measuring arcs were etched by hand so
    they had limited precision.

19
1740 Huntsman Steel
  • Benjamin Huntsman was a clock maker dissatisfied
    with current steel quality. He adopted crucible
    steel from glass mfg.
  • Extremely hard uniform steel perfect for clocks.
  • Helped trigger the industrial revolution.

See how steel is made today
20
1774 Jesse Ramsdens Dividing Engine
  • Triggered by Hadleys sextant, which demanded
    more precise arc divisions.
  • Jesse Ramsdens Dividing Engine used a steel
    tangent screw made using a Huntsman steel cutting
    tool.

21
The Dividing Engine
22
Interchangeable Parts
  • Honore Le Blanc in France gave the idea of
    interchangeable parts for making guns to Thomas
    Jefferson.
  • USA in 1798 became first to make guns with
    interchangeable parts.

23
1808 Maudslays Lathe
  • Used in England to make ships blocks in the
    worlds first modern assembly line. His lathes
    were extremely precise

24
First Standardized Assembly Line
  • Terracotta Army
  • Assembled 2200 years ago.
  • gt1800 life size soldiers, weapons, horses,
    chariots.

25
Ship Blocks
  • Force is reduced by 1/n where n is number of
    lines or sheaves supporting the load.
  • Four sheaves decrease the lift force to 25 Lbs.
    for a 100 Lbs. weight.
  • Why does one need to pull the line 4 ft in order
    to lift weight 1 ft?

Work force x distance
26
Automation not a threat here
  • Much cheap unskilled labor in USA.
  • Interchangeable parts and the assembly line led
    to great growth in jobs and exports.
  • Later, time/motion studies by Taylor and
    Gilbreths perfected the assembly line.
  • Fords B-24 Bomber

27
Accuracy
  • Closeness to true value
  • The accuracy of an analytical measurement is how
    close a result comes to the true value.
    Determining the accuracy of a measurement usually
    requires calibration of the analytical method
    with a known standard.

28
Precision
  • Reproducibility of results
  • Precision is the reproducibility of multiple
    measurements and is usually described by the
    standard deviation, standard error, or confidence
    interval.

29
Accuracy and Precision
30
Taking the long way home
  • 22 Oct.1707 2000 sailors died aboard grounded
    vessels at Scilly isles.
  • The Board of Longitude
  • John Harrisons highly precise spring clock
    designed for ships solved the longitude problem
    in 1759.
  • 15 degree longitude (approx. 1000 mi) per hour.

31
Harrisons H4
  • Completed in 1759
  • 13 cm (5.1 in) in diameter and weighs 1.45 Kg
    (3.2 Lbs).
  • Off by only 39.2 s/47 days or 0.83 s per day
  • Better than twice the required precision.

32
Harrisons H5
  • Tested by King George III in 1772
  • It was off only 0.3 second/day
  • Harrison did not received the 20,000 prize
    from the Board of Longitude in his lifetime.

33
Time Longitude
  • 15o/hr or approx. 1000 mi/hr
  • Check home chronometer aboard ship at high
    noon

Home time ? time Home is You are
1PM 1hr 15o E 15o W
2PM 2hr 30o E 30o W
10AM -2hr 30o W 30o E
34
Longitude
  • An international conference in 1884 set the Royal
    Observatory in Greenwich England as zero
    longitude.
  • A laser beam shoots North along the prime
    meridian.

Readings Taking the Long Way Home
35
  • Longitude lines are the vertical meridian lines.
    Zero longitude is Greenwich England.
  • Latitude lines are the horizontal lines. Zero
    latitude is the equator.
  • The longitude of South tip of Africa is approx.
    20 E longitude 35 S latitude.
  • S. tip of S. America is approx. 75 W longitude
    55 S latitude

36
Longitude Problems
Home Clock Difference New Longitude
118W 2pm 30W 148W
118W 9am 45E 73W
41E 3pm 45W 4W
121E 6am 90E 149W

15deg/hr or 1000mi/hr East is Ahead
37
What you should know
  • Differentiate between astronomy and astrology.
  • Why 12 months in the year and 12 hours each day
    and night.
  • Differentiate between accuracy and precision.
  • Operation of water alarm clock, mechanical clock,
    portable clock and pendulum clock.
  • Astronomy is a science
  • From 12 moons/year
  • Slides 27-29
  • Slides 7-12 and 15-17

38
What you should know
  • Why did astronomers prefer the pendulum clock.
  • The Latin and English translation for AM and PM.
  • The connection between the looker, the sextant,
    and the need for more precision fabrication.
  • Why was le Blanc unsuccessful installing his
    standardized gun parts in France? Pg. 150
  • Increased precision
  • Ante and post meridian
  • Slides 18-21
  • It threatened gunsmiths in Europe.

39
What you should know
  • How a lathe works
  • The connection between Huntsman steel (crucible
    steel), the lathe, tangent screw, dividing engine
    and the sextant.
  • How ships blocks work (LN).
  • Why the assembly line flourished in the U.S., not
    in Europe.
  • Burke 144, video
  • Slides 19
  • Divides work by number of pulleys 25
  • Cheap, abundant unskilled labor in the U.S. not
    in Europe.

40
What you should know
  • How the American System of Manufacturing affected
    U.S. citizens and military
  • Sailing from London at high noon your chronometer
    reads 200PM? What is your new longitude?
  • Describe the construction of Dollonds achromatic
    lens
  • Corrective lenses 1300, the Looker 1608, why
    did it take 300 years for this?
  • Burke 149-151.
  • London is ahead (East) so you are West 2hr x
    15o/hr 30o longitude. 33-35
  • Burke 141 slide 14
  • Burke 134-5
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