Some projects evolve impressively, morphing into innovative creations that defy expectations. One such endeavor is the groundbreaking fluid simulation pendant conceived by [mitxela]. This dazzling piece of jewelry features a matrix of tiny LEDs that ingeniously simulate the movement of liquid, creating a mesmerizing effect that captivates onlookers.

The inspiration behind this pendant seems straightforward: combine art with technology to produce a stunning accessory. However, the journey to perfection was fraught with obstacles. While the complexity of fluid dynamics on a microcontroller could have posed significant challenges, [mitxela] found that the LED matrix presented the most difficulties. Fitting 216 LEDs onto a compact 25-mm diameter PCB while maximizing efficiency proved to be a true test of engineering finesse.

To overcome these hurdles, [mitxela] implemented a clever technique known as diagonal charlieplexing. This method significantly reduced the number of necessary connections, allowing for a dense arrangement of LEDs while remaining manageable for the limited GPIO of the STM32 microcontroller. This innovation not only enhanced the design but also provided a buffer against solder bridging, a common pitfall in such intricate projects.

As with any project by [mitxela], metalworking played a pivotal role in the pendant's creation. The evolution of the gold-plated brass case was particularly noteworthy, with multiple iterations made to reach the final design. The pendant now features a beautifully crafted brass cup that houses a rechargeable LiR2450 battery, a magnetic charging connector, and the core PCB, all elegantly sealed under a watch crystal for both protection and style.

What sets this pendant apart is its fluid simulation capability, which responds dynamically based on the pendant's orientation. The realism is nothing short of extraordinary, effortlessly creating the illusion of liquid motion, bringing life to the accessory as it sways with every movement.

[Mitxela's] latest creation not only showcases remarkable engineering but also blurs the lines between technology and artistry. Watch the captivating demonstration in the video below to see the fluid simulation pendant in action and get a glimpse of the meticulous build process that led to this stunning piece of wearable technology!

This innovative project exemplifies the future of jewelry—where functionality meets design, and science paves the way for artistic expression.