The one thing we have learned over the current pandemic is that we need the internet, and the faster the better. Though cost is surely a hurdle, the amount of bandwidth available has its bottlenecks rooted from the underlying technology. Enter new technology from an Australian Research team who have claimed to have field tested internet speeds as fast at 44.2 terabits per second.
The breakthrough in bandwidth is attributed to a new optical chip that employs optical frequency combs or micro-comb, and has been published by [Corcoran et al] of Monash University. The team exploits the ability of certain crystals to create resonant optical fields called solitons and these form highly efficient optical transmission system. For the uninitiated, optical frequency combs are an optical spectrum of equidistant lines whose values if fixed, can be used to measure unknown frequencies. The original discovery earned Roy J. Glauber, John L. Hall and Theodor W. Hänsch the Nobel Prize in Physics in 2005, and though it is a relatively new field it has seen a lot of activity in the research community.
The experimental setup has a resonator with a free spectral range spacing of 48.9GHz, and from the generated optical fields or lines, 80 were selected. Using a side-band modulator the bands were doubled and eventually with 64 QAM modulation facilitated a symbol rate of 23 Gigabaud. Now at this point, the paper says that this experiment is still an under-utilization of the available resources. The extra connectivity speed may be helpful in gaming and streaming but we will be needing faster drives to get our emails attachments downloaded faster. If you are inspired and want to play with lasers and optical communications, check out the DIY Laser Optical Link.
Thanks [Anil Pattni] for the tip.
Vacuum pumps are powerful tools because the atmospheric pressure on our planet’s surface is strong. That pressure is enough to crush evacuated vessels with impressive implosive force. At less extreme pressure differences, [hopsenrobsen] shows us how to cleverly use kitchen materials for vacuum molding fiberglass parts in a video can be seen after the break. The same technique will also work for carbon fiber molding.
We’ve seen these techniques used with commercially available vacuum bags and a wet/dry vac but in the video, we see how to make an ordinary trash bag into a container capable of forming a professional looking longboard battery cover. If the garbage bag isn’t enough of a hack, a ball of steel wool is used to keep the bag from interfering with the air hose. Some of us keep these common kitchen materials in the same cabinet so gathering them should ’t be a problem.
Epoxy should be mixed according to the directions and even though it wasn’t shown in the video, some epoxies necessitate a respirator. If you’re not sure, wear one. Lungs are important.
Fiberglass parts are not just functional, they can be beautiful. If plastic is your jam, vacuums form those parts as well. If you came simply for vacuums, how about MATLAB on a Roomba?
Thank you [Jim] who gave us this tip in the comments section about an electric longboard.
Continue reading “Vacuum Molding With Kitchen Materials”
If only we had affordable artificial muscles, we might see rapid advances in prosthetic limbs, robots, exo-skeletons, implants, and more. With cost being one of the major barriers — in addition to replicating the marvel of our musculature that many of us take for granted — a workable solution seems a way off. A team of researchers at MIT present a potential answer to these problems by showing nylon fibres can be used as synthetic muscles.
Some polymer fibre materials have the curious property of increasing in diameter while decreasing in length when heated. Taking advantage of this, the team at MIT were able to sculpt nylon fibre and — using a number of heat sources, namely lasers — could direct it to bend in a specific direction. More complex movement requires an array of heat sources which isn’t practical — yet — but seeing a nylon fibre dance tickles the imagination.
Continue reading “Nylon Fibre Artificial Muscles — Powered By Lasers!”