Mitxela’s Tim Alex Jacobs has constructed a collection of creative wearable pendants adorned with a diagonally-charlieplexed LED matrix — which simulate fluid dynamics as they transfer round, after a thought experiment involving a mercury-powered fluid simulation simulation.
“[This is] a handcrafted piece of jewelry operating a realtime FLIP fluid simulation. The enclosure is gold plated, and the show is protected by a watch glass,” Jacobs writes of one of many pendants in query. “I have been seeking to implement a realtime fluid simulation that in the end might create a 3D digital snowglobe. Progress has been made on that entrance, however alongside the best way, we got here up with the Simsim idea, upon which this pendant relies.”
Simsim, unveiled by Jacobs in March final yr, served as a thought experiment for an additional solution to construct the pendants: a round grid of LEDs organized as to be wired to a single energy rail and with the bottom pin uncovered on the rear as pads. Behind the suitably-enclosed PCB is a shot of liquid mercury, which swirls round in a niche on the rear with a purpose to full the circuit and light-weight up the LEDs — successfully simulating a fluid simulation utilizing actual fluid, therefore Simsim. “In essence,” Jacobs defined on the time, “what we’re constructing is one huge mercury tilt swap.”
Mercury, nevertheless, is not precisely the friendliest of supplies, and preserving it from escaping the machine can be a problem — which is why the actual pendants accept a extra conventional simulation, based mostly on Matthias Müller’s work on a two-dimensional FLIP simulator. ” My fluid simulation just isn’t a direct port,” Jacobs says, “however a re-implementation following [Müller’s] tutorial.”
Contained in the housing is an STMicroelectronics STM32L432KC microcontroller, with its Arm Cortex-M4F core overclocked to 100MHz, an Analog Units ADXL362 accelerometer, and an influence system comprised of a Texas Devices TPS3839 supervisor, a low-power TI TPS7A02 regulator, and a Microchip MCP73832 cost controller linked to a LiR2450 battery charged utilizing a magnetic connector on the pendant’s base. The LED matrix, in the meantime, makes use of a twist on conventional charlieplexing referred to as “diagonal charlieplexing” — decreasing the variety of vias required by half and permitting as much as 240 LEDs to be pushed by simply 16 general-purpose enter/output (GPIO) pins, of which the pendant makes use of 216.
Inspiration for the challenge got here from Simsim, a thought experiment in utilizing actual fluid to drive a “fluid simulation” show. (📷: Mitxela)
“I feel I must spend money on but extra gear, be taught extra about jewelry making, and ideally, what I actually need is to have a good metallic store at residence,” Jacobs says of future plans for the challenge. “That both means transferring out of London or making an attempt to give you one thing that matches the house. If we wish to follow and enhance our abilities, nothing beats having our personal store that may be accessed each time and handled nevertheless and messy endlessly.”
An in depth write-up is obtainable on Jacobs’ web site.
