Learning Intention
- To learn how mechanical devices transform energy to do useful work
Notes
Archimedes (287?-212 BCE) was a Greek mathematician who developed the first accurate approximation of pi. He also studied simple machines like the pulley, screw, and lever. Discussing the lever, he claimed, “Give me a place to stand and I will move the world”.
By the 16th century, scientists such as Galileo Galilei were studying the 5 simple machines: the lever, the pulley, the wheel, the wedge, and the screw. Note that the inclined plane was not included. They produced beautiful drawings of the machines.
The making of textiles (fabrics) has been very important historically. It is a very time-consuming process – the historian Bret Devereaux estimates that providing one set of clothing for a Roman family of 6 would take about 7.35 hours of labour per day, every day. Mechanical looms and spinning wheels were inventions that dramatically increased the productivity (the amount of work done every hour) of textile workers.
The Jacquard Loom acts as a mechanical computer. The worker uses punch cards to program the pattern to be woven, then the loom interprets the punch cards to create a unique textile.
How it’s made : Cashmere Pashmina using 200 years old Jacquard Loom technology (2:39)
By the 19th century, mechanical engineers had figured out how to make elaborate “robots” using entirely mechanical means, by combining a variety of gears, cams, pulleys, and shafts.
‘The Writer’ Automaton (4:48)
Van Cleef & Arpels Automate Fée Ondine (8:41 – watch from 6:55 to 8:30)
In the 19th century, machine shops (i.e. woodworking, metalworking, etc.) typically relied on a single source of rotary power, such as a water wheel or a steam turbine. The power source turned a large crankshaft, which provided power to the machines via an elaborate series of pulleys.
Belt & Lineshaft System – the transfer power in a 19th century machine shop (1:46)
This method of providing power to a machine is very dangerous. Imagine how many fingers have been crushed over the years by these tools.
Fairbanks Morse Line Shaft Powered Machine Shop and Lathe. (3:59 – watch 2:15 to 3:15)
How a Wind Up Music Box Works (8:02 – watch first 2:20 only)
Mechanical watches use very very small gears, screws, levers, and springs, but the principals are exactly the same as in larger machines.
This $25,000 Rolex Explorer Was Exposed to Seawater! (52:05 – watch from 35:30 to 36:35)
The same techniques used to create mechanical watches are also used to create “bird boxes”. If you have a spare $5K to $10K, you can get one on eBay.
Reuge Byzance Crystal singing bird box (4:05 – watch first 1:40 only)
Somewhere between a automaton, a music box, and a Rube Goldberg machine is the Wintergatan Marble Machine, which makes music.
Wintergatan – Marble Machine (music instrument using 2000 marbles) (4:32 – watch first 1:45 only)
Bonus video: A screw that is threaded in both directions at once.
Thread in two directions at once. (14:52 – watch 13:00 to 14:25)