Parts used

Glo Slo is Live!

You can now see glo slo in place, outside Parker gallery. Why is it facing the corner? Well, glo slo is positioned so as to minimise the amount of street lights falling on the glow in the dark face.

How It Works

Spin the main arm of glo slo. The pale green material on the 'face' of glo slo is glow in the dark - or phosphorescent. The material used absorbs light, and re-emits green light, dimming over time. This material is 'charged up' by shining a light of a shorter wavelength - higher energy - on it. We charge up this material with an LED light shining back onto the face. Here, a near-UV light has been used; an LED with peak emission around 400 nm. This is why it is still visible to us. This LED is placed on the end of a double pendulum - a 'simple' system which provides a dynamic demonstraion of chaotic motion - just try get it to repeat the same path twice! :) In fact, because the central pivot is from a sander - there is an additional subtle eccentricity to glo slows movement. All combined this provides a light trail of the path the pendulum arm has followed. Wait, what about the blue LED? Ah, that is another story :)

Updates

Update 3

Re-made LED driver circuit. Copied it onto perf-board for mounting onto second arm. Mounted battery, changed up the clearances a bit to help it fit.

Update 2

The dynamics was an unknown, so I got to playing with that. The arms are unweighted at this stage. It was notable that the main arm does not return to the high position, after losing the initial energy. While spinning the arms while holding the board it became clear that quite a bit of energy would be lost (won't spin very long) if glo slo did not have a firm mounting. Alternatively, having lighter arms, using a fly-wheel, or more counter balance would likely help.

Update 1

Materials gathered for most of project, excluding mounting frame. Materials check; wow! this glow in the dark vinyl glows for a long time. Too long? We will find out... The banner image for this page was made using this vinyl. Made a test circuit for the LED, confirmed all is well.