Zombie projects

I post many of my projects on public sites for two reasons: (a) they *might* be useful to other people and (b) they *will* get lost if I store them on my home computer. It surprises me when I have a project that has been around for a while and then, seemingly out of the blue, there’s some activity. That is the case with my goiolink package that interfaces Vernier’s Go!Link adapter (and compatible sensors) with Mathematica running on a Raspberry Pi. (Clearly, something that many, many people are doing…)

So I was reasonably surprised that within the span of a few weeks earlier this semester, I received several communications about my code. There is clearly some small interest in reproducing my setup but folks are having problems following the directions. I have little experience in distributing software, and because the Vernier/Mathematica/RPi crowd is a fairly small one, I have access to very few beta testers. If there’s any hope of others using my software, it looks like I’ll need to streamline the installation. So here it goes.

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The Pi Projector

In a week, I return to teaching classes, and my course is going to meet face to face. The pandemic has kept me indoors more or less since the week before Thanksgiving, so I am itching to see students. That said, I’m aware that the virus is not at all contained, and there’s little chance for me to get the vaccine in the near future. [Yes, as a faculty member, I’m allowed to get the vaccine, and I can get it … sometime in April … when classes will be essentially over.

Thanks, government.

Enough of my soap box. I wanted a way to interact with students during office hours, but was worried if we were trying to show work on a computer screen or piece of paper (and thus breaking social-distancing guidelines). I decided solve this problem as I normally do lately – with the help of a Raspberry Pi.

Enter – the Pi Projector.

The Pi Projector, complete with CNC case and a cooling fan!
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LED spectroscopy

I’m working on a project that will include using LEDs as light sensors, and one of the first tasks is to learn a bit more about the wavelengths of light that are emitted by an array of LEDs. Since I’ve recently created a Mathematica interface to an Ocean Optics spectrometer (on a Raspberry Pi, naturally), the first task was pretty straightforward.

Emission spectra of several LEDs. rgb(b,g,r) are in a common cathode RGB led while the others are varieties from Adafruit.
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