inconsistently improving since 1982


Category : AnaLuma, Physical Computing · No Comments · by Dec 31st, 2013

A Note on Stepper Motors

Category : AnaLuma, Physical Computing · No Comments · by Dec 5th, 2013

Stepper motors are really tough to work with. For the AnaLuma project, I decided to go with 2 28BYJ48 DC 5V 4-phase 5-wire stepper motors with these cool little driver boards (Amazon). They seemed to work great on the breadboard, but when integrated into the project, they were just too weak. After hours and hours of trial and error, I found that they worked much better arranged as a bipolar stepper motor, rather than a unipolar stepper motor, using an H-bridge (more info). This essentially doubles the power by using the full coil rather than half.

The most idiotic thing is that when I finally wired this all up, it worked great on the board, then failed again when I integrated it into my project. Once again the motors were weak. The reason? I had swapped two of the signal wires. Let this be a lesson in working hard in late hours: Chances are, when things aren’t working, there’s no problem with the hardware, or the software, or you: it’s just late.


AnaLuma V1 Complete

Category : AnaLuma, Physical Computing · No Comments · by Dec 5th, 2013

I give you AnaLuma V1.

AnaLuma Design Details

Category : AnaLuma, Physical Computing · No Comments · by Nov 13th, 2013

In this post I’m continuing to design the AnaLuma (originally called the Sun Light) first described here.

whole diagram

AnaLuma: Initial Concepts

Category : AnaLuma, Physical Computing · No Comments · by Nov 5th, 2013


Living indoors we gain new comforts. But we lose our exposure to the open sky and to the sun, breaking us away from the rhythm of sunrises and sunsets, inclination and declination.


The sun communicates our place during the day and the year, and our bodies have evolved to expect it to balance our lives.

AnaLuma attempts to provide the benefits of indoor lighting with the cadence and natural influence of the sun. The light is meant to be left on all the time in a large room, where it will provide a surrogate sun that mimics the motion of the sun through the days and seasons.

The AnaLuma is a spherical hanging lamp with a full-spectrum lightbulb inside. The sphere has a single opening in its shell that acts as a iris to represent the sun. Over the course of the day, the body of the lamp moves to align the projected sun with the real sun.

Around the base of the lamp is a semicircle of dark translucent material fading from orange to blue. In the evening hours the lamp continues to track the sun’s position, and this filter simulates the sunset and the soft blue glow of evening light.