Batteries placed in harm’s way need to be protected. A battery placed where a breakdown could endanger a life needs to be protected. Lithium-ion batteries on the bottoms of electric cars are subject to accidental damage and they are bathed in flame-retardant epoxy inside a metal sled. Phone batteries are hidden behind something that will shatter or snap before the battery suffers and warrant inspection. Hoverboard batteries are placed behind cheap plastic, and we have all seen how well that works. Batteries contain chemicals with a high density of energy, so the less exploding they do, the better.
Researchers at Oak Ridge National Laboratory have added a new ingredient to batteries that makes them armored but from the inside. The ingredient is silica spheres so fine it is safe to call it powder. The effect of this dust is that the electrolyte in every battery will harden like cornstarch/water then go right back to being a liquid. This non-Newtonian fluid works on the
principal principle of shear-thickening which, in this case, says that the suspension will become harder as shear force is applied. So, batteries get rock hard when struck, then go back to being batteries when it is safe.
Non-Newtonian fluids are much fun, but we’re also happy to see them put to use. The same principle works in special speed bumps to allow safe drivers to continue driving but jolts speeders. Micromachines can swim in non-Newtonian fluids better than water in some cases.
Like it or not speed bumps are an essential part of our road infrastructure especially in built-up places like near schools [Business Insider UK] reports non-Newtonian liquid filled speed bumps are being tested in Spain, Israel and Germany.
Traditional speed bumps do have their drawbacks; damage to the underside of low vehicles is common. While they should be uniform in dimensions, in practice they can vary significantly, making driving over unfamiliar bumps a bit unpredictable. This is all set to change with non-Newtonian bumps which are soft to drive over at slow speeds but for speeding drivers they harden up and act more like traditional bumps. This gives drivers following the letter of the law a better driving experience whilst still deterring speeding drivers..
Non-Newtonian materials are nothing new but we think this is a great way of purposing these type of materials. Roads are getting smart whether you like it or not. It’s time to embrace technology and improve our commutes. Continue reading “Smart Speed Bumps Slow Only Speeding Cars”
Navid Gornall is a creative technologist at a London advertising agency, which means that he gets to play with cool toys and make movies. That also means that he spends his every working hour trying to explain tech to non-technical audiences. Which is why he was so clearly happy to give a talk to the audience of hardware nerds at the Hackaday Belgrade conference.
After a whirlwind pastiche of the projects he’s been working on for the last year and a half, with tantalizing views of delta printers, dancing-flame grills, and strange juxtapositions of heat sinks and food products, he got down to details. What followed was half tech show-and-tell, and half peering behind the curtain at the naked advertising industry. You can read our writeup of the highlights after the video below.
Continue reading “Navid Gornall Eats His Own Face”
The idea of using nanobots to treat diseases has been around for years, though it has yet to be realized in any significant manner. Inspired by Purcell’s Scallop theorem, scientists from the Max Planck Institute for Intelligent Systems have created their own version . They designed a “micro-scallop” that could propel itself through non-Newtonian fluids, which is what most biological fluids happen to be.
The scientists decided on constructing a relatively simple robot, one with two rigid “shells” and a flexible connecting hinge. They 3D-printed a negative mold of the structure and filled it with a polydimethylsiloxane (PDMS) solution mixed with fluorescent powder to enable detection. Once cured, the nanobot measured 800 microns wide by 300 microns thick. It’s worth noting that it did not have a motor. Once the mold was complete, two neodymium magnets were glued onto the outside of each shell. When a gradient-free external magnetic field was applied, the magnets make the nanobot’s shells open and close. These reciprocal movements resulted in its net propulsion through non-Newtonian media. The scientists also tested it in glycerol, an example of a Newtonian fluid. Confirming Purcell’s Scallop theorem, the nanobot did not move through the glycerol. They took videos of the nanobot in motion using a stereoscope, a digital camera with a colored-glass filter, and an ultraviolet LED to make the fluorescent nanobot detectable.
The scientists did not indicate any further studies regarding this design. Instead, they hope it will aid future researchers in designing nanobots that can swim through blood vessels and body fluids. We don’t know how many years it will be before this becomes mainstream medical science, but we know this much: we will never look at scallops the same way again!
Continue reading “Nanobots Swim like Scallops in Non-Newtonian Fluids”