Anyone who’s ever cut ribbon, grosgrain or otherwise, may be dismayed by the frayed edge. There are methods of avoiding this, like cutting the ribbon diagonally, or double-diagonally into a forked point, or cutting it straight across and cauterizing the threads with a lighter. But if you have a thirteen dozen baker’s dozens’ worth of goodies to festoon, ain’t nobody got time for that.
[IgorM92] made this hot wire ribbon cutter for his wife, who has a yummy-looking baking business. It combines the cutting and the heat-sealing into a single step by using the heating element from an old soldering iron. If you don’t have one of those, you could just as easily use the nichrome wire from an old hair dryer, a toaster, or wire-wound resistor.
Since the idea is essentially shorting a power source to heat up a wire, it should be done safely. [IgorM92] used a phone charger to condition mains power down to 5 V. There isn’t much else to the circuit, just a rocker switch, a power-indicating LED, and its resistor, but this simple project will no doubt save a lot of time and labor. Burn past the break to watch it ramp up production.
You may have seen the Ruideng range of programmable power supply modules from China: small and relatively inexpensive switch-mode buck converters, with microprocessor control and a front panel featuring a large colour OLED screen. Given 30 volts or so they can supply any lower voltage with the extra bonus of current limiting. They’ve been so successful over the several years they’ve been available that they’ve even spawned their own Chinese clones, and countless hacker projects, for instance on the DPS300X and DPS500X models.
Late last year a new module came from Ruideng, the Riden-branded RD6006 combines the basic idea of the previous modules with an extremely flexible front panel with full keypad and rotary encoder, creating something like the front panel to a decent bench power supply but without the accompanying power supply. I ordered one, waited for it to clear customs, took it to my bench, and reviewed it. Continue reading “Review: The Riden RD6006W DC Power Supply Module”→
COVID-19 can seem like a paper tiger, when looking at bare mortality rates. The far greater problem is the increase in fatalities as health systems are stretched to the limit. With thousands of patients presenting all at once, hospitals quickly run out of beds and resources and suddenly, normally survivable conditions become life threatening. One Italian hospital found themselves in such a position, running out of valves for a critical respirator device needed to save their patients. Supplies were running out – but additive manufacturing was able to save the day.
While the article uses the term “reanimation device”, it’s clear we’re talking about respirators here, necessary to keep patients alive during respiratory distress. The valve in question is a plastic part, one which likely needs to be changed over when the device is used with each individual patient to provide a sterile flow of air. After the alarm was raised by Nunzia Vallini, a local journalist, a ring around of the 3D printing community led to a machine being sent down to the hospital and the parts being reproduced. Once proven to work, things were stepped up, with another company stepping in to produce the parts in quantity with a high-quality laser fusion printer.
Researchers from Denmark’s Aarhus University have developed a method for autonomous drone scanning and measurement of terrains, allowing drones to independently navigate themselves over excavation grounds. The only human input is a starting location and the desired cliff face for scanning.
For researchers studying quarries, capturing data about gravel, walls, and other natural and man-made formations is important for understanding the properties of the terrain. Controlling the drones can be expensive though, since there’s considerable skill involved in manually flying the drone and keeping its camera steady and perpendicular to the wall it is capturing.
The process designed is a Gaussian model that predicts the wind encountered near the wall, estimating the strength based on the inputs it receives as it moves. It uses both nonlinear model predictive control (NMPC) and a PID controller in its feedback control system, which calculate the values to send to the drone’s motor controller. A long short-term memory (LSTM) model is used for calculating the predictions. It’s been successfully tested in a chalk quarry in Denmark and will continue to be tested as its algorithms are improved.