As the Iraqi army retreated at the end of the first Gulf War, they took the term “scorched Earth policy” quite literally. Kuwaiti oil wells were set alight en masse, creating towering infernos that blackened the sky.
As it turns out, extinguishing a burning oil well is no easy feat. In the face of this environmental disaster, however, a firefighting team from Hungary made a name for themselves out on the desert sands, astride a jet-engined tank named Big Wind.
3D printing is a popular process, though one of the hangups is that parts are typically produced in just one flat color. [Aad] has been working on a simple modification to his Prusa i3 printer, however, that enables the production of full-color parts.
Note the dual vertical assemblies – one carrying the extruder, the other carrying an inkjet print head.
The hack is simple, consisting of a second vertical frame added on to the printer. Rather than mounting a second extruder, however, there’s a inkjet printer head delivering CMYK water-based inks. After the main extruder lays down each layer of clear PLA plastic, the print is then moved under the inkjet head, which lays down colored inks before the next layer is printed, as seen in this print video.
[Aad] notes the results are presently imperfect. The ink seems to bleed between layers, mixing with the plastic after it is laid down. Further testing with different inks and filaments is in the pipeline, however, aiming to improve quality and contrast of the results.
While addressable LED strips are all the rage, [Mike] from [mikeselectricstuff] has been working on an installation using the more basic two-wire strips that are simply controlled via PWM dimming. He’s recently figured out a tidy way to send sensor signals down these strips without adding any additional cabling.
The circuit in question.
The build uses 24 V LED tape, which consists of gangs of 6 LEDs in series with a forward voltage of 3V. Thus, these strips don’t even begin to light until approximately 18V is across them.
By adding a 15 V Zener diode and a resistor across the MOSFET which dims the LEDs, a voltage of around 9 V can be put across the LEDs without lighting them up when the MOSFET PWM dimmer is in its off phase. A PIC10F322 microcontroller and an accelerometer can then be run from this voltage, with the aid of a 3.3 V regulator wired in parallel with the LEDs. The regulator must also be able to handle the full 24 V when the LEDs are switched on.
A transistor is also wired up, switching a 2.2 K resistor in parallel with the LEDs. When turned on by the PIC, this transistor causes roughly a 10 mA current to flow through the Zener diode and its series resistor. The voltage developed across that series resistor can be measured as the transistor is turned on and off. In this case, the pulse width used to turn that transistor on is relative to motion detected by the accelerometer on the end of the LED strip.
Turning the LEDs on at 100% duty cycle prevents the system working, as the pulse widths generated by the sensor circuit can’t be detected when the LED line is held high all the time. However, in practice, it matters not — running the LEDs at a maximum 98% duty cycle eliminates the issue.
It’s an ingenious way to send sensor signals down a two-wire LED strip, even if it does take a second to wrap one’s head around it. It also seems to do a great job of adding motion-reactive effects to the LED strips in question. It’s not the first LED project we’ve seen from [Mike], either. Video after the break.
As the world grapples with the issue of climate change, there’s a huge pressure to move transport away from carbon-based fuels across the board. Whether it’s turning to electric cars for commuting or improving the efficiency of the trucking industry, there’s much work to be done.
It’s a drop in the ocean in comparison, but the world of motorsports has not escaped attention when it comes to cleaning up its act. As a result, many motorsports are beginning to explore the use of alternative fuels in order to reduce their impact on the environment.
Sales of electric vehicles continue to climb, topping three million cars worldwide last year. All these electric cars need batteries, of course, which means demand for rechargeable cells is through the roof.
All those cells have to come from somewhere, of course, and many are surprised to learn that automakers don’t manufacture EV batteries themselves. Instead, they’re typically sourced from outside suppliers. Today, you get to Ask Hackaday: why aren’t EV batteries manufactured by the automakers themselves? Continue reading “Ask Hackaday: Why Don’t Automakers Make Their Own EV Batteries?”→
Pascal is not one of the biggest programming languages these days; it’s fallen into the background as the world moved on to newfangled things like C#, Python and Java. However, the language has its fans, one of whom put together a new compiler which targets retro platforms – and it goes by the name Turbo Rascal.
The list of supported platforms is extensive, with Turbo Rascal able to compile highly-optimized binaries for the C64, Amiga 500, BBC Micro, IBM PC, Atari ST, Game Boy, Amstrad, NES, ZX Spectrum, and more. There’s a usable IDE and even an included graphics editor for getting projects put together quickly. Also known by its full name of Turbo Rascal Syntax Error, or TRSE, it’s the work of one [Nicolaas Groeneboom].
The compiler runs on 64-bit Windows, Linux, and OS X, and there are extensive tutorial videos available on YouTube, too. Thus, there’s no excuse not to start developing a new retro game immediately. Check out the demo video below, and remember – as long as we keep using it, Pascal isn’t dead!
Building basic computers from the ground up is a popular pastime in the hacker community. [Kevin] is one such enthusiast, and decided to whip up a video interface for his retro Z80 machine.
The output from [Kevin]’s build.The computer in question is a RC2014 Classic ][, a popular single-board 8-bit computer kit. As standard, it doesn’t have a video output, so [Kevin] built one using the PIO interface of the Raspberry Pi Pico.
74-series logic is pressed into service to handle address selection, enabling the Pico and Z80 to effectively communicate. Wait states in the Z80 are used to avoid the vintage chip tripping over when the two are communicating. The Pico outputs video in 160 x 120 resolution with eight bits of color per pixel, using a simple resistor-ladder DAC to do basic VGA.
The build serves as a great way to get familiar with programming both the Pi Pico and the Z80 itself. With that said, it’s probably possible to simply just emulate the Z80 on the Pi Pico given the latter runs at a default clock rate of 125 MHz, eclipsing the RC2014’s snail-like 7.3728 MHz main clock.
