Printed circuit boards used to be green or tan, and invariably hidden. Now, they can be artful, structural, and like electronic convention badges, they are the entire project. In this vein, we find Open LEV, a horseshoe-shaped desktop bauble bristling with analog circuitry supporting an acoustic levitator. [John Loefler] is a mechanical engineer manager at a college 3D printing lab in Florida, so of course, he needs to have the nerdiest stuff on his workspace. Instead of resorting to a microcontroller, he filled out a parts list with analog components. We have to assume that the rest of his time went into making his PCB show-room ready. Parts of the silkscreen layer are functional too. If you look closely at where the ultrasonic transducers (silver cylinders) connect, there are depth gauges to aid positioning. Now that’s clever.
Using SPICE to simulate an electrical circuit is a common enough practice in engineering that “SPICEing a circuit” is a perfectly valid phrase in the lexicon. SPICE as a software tool has been around since the 70s, and its open source nature means there are more SPICE tools around now to count. It also means it is straightforward enough to use with other software as well, like integrating LTspice with Python for some interesting signal processing circuit simulation.
[Michael]’s latest project involves simulating filters in LTspice (a SPICE derivative) and then using Python/NumPy to both provide the input signal for the filter and process the output data from it. Basically, it allows you to “plug in” a graphical analog circuit of any design into a Python script and manipulate it easily, in any way needed. SPICE programs aren’t without their clumsiness, and being able to write your own tools for manipulating circuits is a powerful tool.
This project is definitely worth a look if you have any interest in signal processing (digital or analog) or even if you have never heard of SPICE before and want an easier way of simulating a circuit before prototyping one on a breadboard.