Here, automata guru Dug North rounds up four expedient methods for improvising a worm drive given an on-hand spur gear. Digging through our archives also reveals this interesting method for coming at the problem from the other direction, i.e. improvising a spur gear for an on-hand worm!
Bruce Parker, former Chief Scientist and eleven-year veteran of NOAA’s National Ocean Service, wrote this fascinating article in the September issue of Physics Today. It covers the technical history
of the science of tide prediction leading up to the beautiful mechanical computers developed in the nineteenth and early twentieth centuries to quickly extrapolate recorded tide patterns into useful predictions, and goes on to explain how those computers were critical in planning the Normandy landings.
For those of you with an overwhelming desire to build your own subatomic particle accelerator, look no further than this Instructable by Xellers, which shows you how to convert a wine bottle into a cathode ray tube (CRT). Of course, that’s not all you need: other ingredients include a two-stage vacuum pump, a neon sign […]
“Acoustic metamaterial” may sound exotic, but researchers in France have managed to assemble one from a few multipacks of cola cans. Arranged in a grid, the drinks cans act as a superlens for sound, focusing acoustic waves into much smaller regions than their metre-long wavelengths typically allow. The cans act as resonators, directing the volume […]
This video is short, and really pretty boring if you don’t know what’s going on. Shown is a chunk of new alloy that undergoes a phase change, at about 125C, from a nonmagnetic material to one that is strongly magnetic. If you bias the system with an additional, permanent magnet, heating the system past the transition temperature produces an electric current in a nearby coil, thereby converting heat to electricity.
When we last checked in on Ben Krasnow’s homemade SEM, he had just achieved his first successful image with the device. As his latest video shows, the project has come a long way since then. It’s a long clip, by internet standards, at almost 10 minutes, but Ben does a great job of communicating what he’s doing and why, taking us through each step in the imaging process, from loading the sample, through pumping down the vacuum chamber and powering up the electronics, to fine-tuning the image itself.
Fifteen uncoupled simple pendulums of monotonically increasing lengths dance together to produce visual traveling waves, standing waves, beating, and (seemingly) random motion. The period of one complete cycle of the dance is 60 seconds. The length of the longest pendulum has been adjusted so that it executes 51 oscillations in this 60 second period. The […]
