Mad Dog 21/21: Torque Is Cheap
October 26, 2015 Hesh Wiener
“Screw it,” said Archimedes of Syracuse, refusing to surrender to the gravity of the situation. Around 250 B.C., he developed a water pump that converted torque to lift. It was a helix inside a cylinder, a progenitor of propellers and augers. Archimedes also devised ingenious ways to calculate volume and mass. Archimedes’ two principal pursuits, applied physics and applied math, are as important today as ever, particularly for IBM’s current passion, the Internet of Things.
The “eureka” story has been around a long time. Notably, an essay on floating bodies that very likely originated with Archimedes appears in a palimpsest, a manuscript on parchment that recycled an older text on the costly medium. In this case, the more recent text was a 13th century prayer book. The older, original text of what has come to be called the Archimedes Palimpsest is a 10th century compendium of various works by the great Greek mathematician passed down through the generations. Although the palimpsest was created 1,200 years after Archimedes died and overwritten 300 years later, it is believed by scholars to be an authentic rendition. It is written in Byzantine Greek, a linguistic descendant of the Doric Greek of the Greeks living in Sicily during Archimedes’ lifetime.
The palimpsest, which includes seven treatises, the most relevant called On Floating Bodies, provides an academic foundation for the colorful tale of Archimedes and the crown. Basically, Hiero, the ruler of Sicily, worried that a crown made for him was a fake, made partially of silver rather than the pure gold the king had given his goldsmith. Hiero asked Archimedes to figure out a way to test the purity of the gold in the crown without destroying it. Archimedes had the problem on his mind when he took a bath and as he noticed the way the water level rose as he got into the tub, he had an insight. He figured out that the crown would displace the same amount of water as a bar or lump of pure gold with the same volume . . . if the crown was pure gold. If, however, the crown was part silver, which is less dense than gold, it would have to have a larger volume to reach the correct weight and thus, if immersed, would displace more water than a pure gold crown of the same weight.
So, the testing process came to this: Archimedes would get pure gold of the exact weight given by the king to the goldsmith. He would then put the gold in a vessel and fill the vessel to its brim with water. Next, he would remove the gold leaving the water in place. Finally he would put the crown in the water. If the water rose to the same level the crown had the correct volume and it was therefore pure gold. If, on the other hand, the vessel overflowed, the overflow would have the same volume as the excess volume occupied by the impure crown. This would be the case no matter how ornate the crown might be, whatever its shape.
When Archimedes, sitting in a tub, came up with the scheme he is said to have jumped out of the bath and run naked through the streets of Syracuse shouting, “eureka,” which means “I found it.” He seems to have found more than a method of assay. As the story goes, the crown was in fact a fake. The goldsmith had to answer to the king. Clever Archimedes was the hero of the day.
Many matters involving the determination of volume were of paramount importance to Archimedes, and a sculpture referring to his famous proof that a sphere enclosed in a cylinder of the same height has 2/3 the cylinder’s volume–and 2/3 of its surface area, too–was put on his tomb. But then the tomb’s location was apparently lost. It was rediscovered a century or so after Archimedes’ death by the Roman orator Marcus Tullius Cicero. A connection of Cicero to Sicily is preserved in, of all places, the Finger Lakes district of central New York state, where the town of Tully, named for Cicero, with its intellectual resources, is situated a half hour’s drive from the city of Syracuse.
Archimedes is also famous in myth and fact for the development of war machines to defend the port of Syracuse. He is credited with the creation of catapults and of cranes that could capsize or sink ships nearing the walls of the port. These machines were based on Archimedes’ understanding of levers and pulleys, on his mastery of torque.
For quite a long time there were few improvements made to the devices invented, improved, or perfected by Archimedes, who was far ahead of his times. Of all the technologies advanced by Archimedes, the screw has arguably been the slowest to mature. Screw pumps made today, used for irrigation, are pretty much the same as the ones devised by Archimedes. But the technology of screw fasteners continues to evolve to this very day, and with it the machines used to drive screws.
In Archimedes’ time and for centuries thereafter, the most widespread practical application of the screw was to turn torque into pressure, powering presses used to make olive oil and to extract juice from fruit. The screws in these presses were wooden and quite large, and this was the state of the art more than 1600 years later when screw mechanisms were used to actuate Gutenberg’s printing press. Small metal screws, so widely used today, simply didn’t exist until the Renaissance. The metalworking technologies and skills involved in the manufacture of screws arose in Europe during the 14th and 15th centuries. One well-known application, even several hundred years ago when screws were painstakingly made by hand, was in the assembly of guns.
At the time, the fasteners used in most other applications, from carpentry to construction to shipbuilding, were nails or pegs, items that are a lot simpler to manufacture. While large wood lathes predate Archimedes, smaller lathes suitable for metalworking were developed much later. Canon whose barrels were cut with a boring machine, a cousin of the lathe, didn’t appear until the 18th century.
Even when lathes and thread-cutting machines became widely available during the Industrial Revolution, for quite some time the only screws that could be mass produced were had cylindrical rather than tapered shafts, the kind commonly called machine screws. Finally, in the mid-19th century, inventors perfected machines to economically cut tapered screws that could be used in wood or metal that wasn’t threaded before fastening. Even then, most screws were of poor and inconsistent quality, which held back the advancement of manufacturing. Eventually, developments such as the Robertson square drive screw, adapted by, among others, Ford for use in its Model T cars, brought about permanent advancements in the mass production of complex machines.
Today, a hundred years after Robertson permanently elevated fastener technology to a higher level, the tools used to build (and repair) most everything are finally gaining the sophistication to take advantage of leading edge fasteners. A key element in this process has been the adoption of electronic technologies widely used elsewhere, such as in smartphones, to improve the versatility of hand tools.
Currently, everyone from professional tradesmen to home do-it-yourselfers seems to be migrating from the use of nails driven by hammers (and nail guns) to high-technology screws and tools to insert them.
Modern power screwdrivers sense the operator’s hand motion and amplify it. These tools react when nudged into action, turning clockwise or counter-clockwise in response to the user’s hand motion. When they are running they light the work area. These tools don’t yet have vision systems of their own and instead depend on the operator’s eye-to-hand coordination for guidance, but smarter screwdrivers with capabilities that resemble those in factory floor robots are on the way. Handheld power screwdrivers use non-slip fast change chucks that accept a wide variety of bits. These tools can not only drive screws, they can also drill and countersink holes or spin nuts onto bolts.
These gadgets are catching like wildfire, not only because they are so ingeniously engineered but also because they are very inexpensive. Small power screwdrivers can cost as little as $20, although some of the more upscale models can cost close to $100. Even so, these tools are widely viewed as items of immense practical value because they are such amazing time-savers.
When people need more powerful tools they move up a level to cordless, electronically controlled drill/drivers, impact drivers, and hammer drivers. These power tools weigh just a couple pounds apiece and typically cost only less than $150 per tool. Nevertheless, they enable home builders to efficiently install framing, mount drywall and put together wooden decks; they quickly pay for themselves. Moreover, the resultant work is far sturdier than comparable work done with hammers and nails. To pick just one simple example, a wooden deck built with nails often warps over time, lifting planks and increasing maintenance costs. The same boards held in place by screws are very unlikely to break loose even though time and weather produce substantial stresses within each plank, putting a lid on repair costs.
To control their motors and manage their use of power, handheld power tools use microprocessors and firmware similar to the technology in mobile communications devices. Like power screwdrivers, drills and drivers have work area lights but lack vision input. But they do have very effective electromechanical drives. All but the least costly power tools made today use light and capable lithium-ion battery packs. Motors on moderately priced tools use brush-and-commutator designs that can be controlled with relatively primitive circuitry. Newer and thus far more costly tools have brushless motors that take advantage of rare earth permanent magnets and very clever switching circuitry to provide quite a bit of torque, very long battery life, and the technical possibility of incorporating load sensors, temperature sensors, rotational velocity sensors, and other smart or self-aware features. The upshot is that a small handheld driver with smart torque management can sink 3-inch lag bolts all day long, if the operator has a spare battery and rapid charger on hand. Moreover, a smart driver using high-tech screws used by a craftsman with decent skills and a bit of experience will hardly ever tear apart a screw head or breaks the shaft of a fastener.
Today’s tools require manual adjustment of their clutch mechanisms, typically with a ring on the chuck that is a bit like the adjustment ring on a manual camera. But the next step, the centralized and automated setting of tools to match for each phase of a construction project, is just around the corner. The missing elements are jobsite or workshop servers . . . and data radios in the tools. It is possible, even likely, that jobsite local smart tool networks will be based on tablets and communications technologies similar to the ones used in smart home security systems. But right now the situation is in flux.
Technology vendors, including IBM, can get in on the ground floor as construction and workshop technology evolves to plug handhold tools and the craftsmen using them into the Internet of Things. Sure, jobsite automation has a lot in common with factory automation, giving industrial automation suppliers an advantage. But sometimes technology leaps ahead in ways that leave legacy vendors beached while providing new entrants outstanding opportunities. The automation of tools and workshops could rhyme with the way audio entertainment evolved from physical tape distribution to streaming distribution, rapidly shifting the entire business from the Walkman to the iPod.
It looks like there is a huge opportunity about to emerge, but until the Internet of Workshop Things reveals its Steve Jobs and its iPod, nobody can guess what company will be to the IoT what Apple was to personal media players (and much more). When it comes to the advancement of industrial computing, IBM, the Trumpish trumpeter of the Internet of Things, is nowhere to be seen. IBM may be happy to set up offices in snazzy San Francisco or the geek elite’s Kendall Square, but the company just doesn’t seem to be very interested in actually getting any of its employees’ hands dirty. And that is not a good way for IBM to become a live player in the Internet of Things.
Maybe IBM can win some or all of this market by working it top down, providing service backbones to Home Depot, Lowe’s, Tractor Supply, Ace Hardware, and their ilk, possibly finding a way to tap into Harbor Freight.
When it comes to automating workshop tools and tying them into cloud-based systems that can learn procedures and ultimately help the craftsmen using the tools, there is some pretty advanced communication technology already in use when machinists, mechanics, carpenters, and even DIY enthusiasts want to prepare work and later measure the outcome of workshop or factory activities.
Builders routinely use laser-based devices to measure distances, areas and volume and to read angles, ascertaining what is level and what is plumb. Some of these devices can talk to phones, tablets or PCs. Machinists have long since measured distances and sizes with electronic micrometers and calipers that talk to computing devices via USB interfaces, but until recently the only widely available devices were those built by the world’s leaders in metrology, such as Mitutoyo or Fowler. Today, versions of these devices for less demanding applications are cheap enough for the home woodworker or mechanically inclined hobbyist.
So, there seem to be strong indications that networks of tools and instruments, if not the whole Internet of Things, already pretty routine in factories, will soon become a practical aspect of industrial processes carried out in the field, such as homebuilding, and in small workshops, such as auto repair centers. Where there are benefits ranging from improved personnel management to more accurate monitoring of tools and materials, smart and connected devices will appear in the hands of contractors, including solo craftsmen, and ordinary homeowners who wish to take on house and garden maintenance tasks.
To one observer, it looks like the development of this part of the Internet of Things is going to be a bottom-up more than a top-down process. If IBM wants to be a part of it, it can try to win over the planners shaping the future of tool vendors or perhaps tool makers like Bosch, Makita or Stanley, it may have to find a way to hunker down with the blue collar folk and their upstream suppliers. It might not be that difficult, even if it seems unlikely. The company’s big shots could start by visiting one of their own machine shops to see how IBM’s own Things might be Internetted. There isn’t a machine shop in white-collar Armonk, but IBM might still have one in what’s left of Pokie or maybe Endicott, which aren’t all that far away, in case anyone at headquarters actually cares, and in case they haven’t yet gotten around to turning off the last of the lights in the old factories.