![]() The restoring force on a torsion pendulum is a torsion spring – a narrow ribbon of metal, usually Invar to avoid temperature-induced rate changes – from which the pendulum hangs.) (A conventional pendulum is brought back to its resting position by gravity, which is said to be the "restoring force" on the oscillator a torsion pendulum rotates in a horizontal plane rather than swinging in the vertical plane like a conventional pendulum. The Atmos pendulum beats very slowly, at only one oscillation per minute, the Long Now prototype's pendulum beats at the same rate. Like the Atmos pendulum, it's suspended from an Invar torsion spring. The pendulum itself is a three-armed torsion pendulum, similar to the one found in an Atmos clock. The clock shows mean local solar time, so there's a mechanism for correcting for the Equation of Time as well. The latter consists of a piece of metal that, when struck by sunlight at noon, will change its dimensions, and input a noon correction to the timekeeping mechanism to compensate for any accumulated inaccuracy due to rate fluctuations in the pendulum. ![]() Nuclear power as an option was rejected early on (for various fairly obvious reasons, including poor maintainability over such a long time period) and no single timekeeping source was satisfactory – Hillis and his team considered a number of very intriguing options, including solid material flow, gravitational tidal fluctuations, and a simple spring and mass they eventually settled on a combination of a pendulum, and an additional solar correction component. ![]() No one to my knowledge has ever tried to build something that stands a rational chance of running for 10 millennia, and the process of developing key aspects of this engineering challenge included evaluating candidate power sources, timekeeping mechanisms, materials, and so on. The prototype is almost nine feet tall overall and was constructed in order to test the key concepts behind the project, which was originally conceived by computer scientist, inventor, and entrepreneur Daniel "Danny" Hillis (who's famous for his work on massively parallel computer architecture) in 1986. While visiting London with Breguet last week, we were able to view the prototype, which is part of an exhibition called "The Making Of The Modern World." The clock is two floors down from the main draw for watch enthusiasts, which is the Clockmaker's Company collection of clocks and watches (which features a number of Breguets, which we'll be looking at soon) but it's well worth the detour, to put it mildly. Prior to the installation of the full scale final mechanism, however, the Long Now Foundation (which was established in 1996 and which "hopes to provide a counterpoint to today's accelerating culture and help make long-term thinking more common") created a prototype that is in itself an extremely impressive achievement, and which is currently on long-term loan to the Science Museum in London. Underwritten in part by a $42 million donation from Amazon founder Jeff Bezos, the Clock Of The Long Now – a gigantic mechanism sitting inside a 500-ft.-deep vertical tunnel – is designed to run for at least 10,000 years, with minimal human intervention. Somewhere in the Texas desert, one of the most remarkable engineering projects in the history of clockmaking in particular, and horology in general, is unfolding. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |