Hi, this is Wayne again with a topic “Making Fun: Brainwave Zen Garden”.
Brainwave headsets are fun, but the usual charts and graphs aren’t a very exciting visual. I want my headset to give me feedback, as i practice meditating, but in a relaxing way i decided to use electroencephalography to create a new take on the desktop zen garden to reduce cost and complexity. I’M going to limit the travel of the rake to a single axis and spin the garden underneath like a phonograph. This lazy susan is perfect. I played around with many rake systems and went with the simplest thing that worked a solid aluminum rod kept on track by an aluminum tube.
I made a little block to hold the tubing in place near the edge of the garden. These old vex parts went together easily to form a mechanism that pushes and pulls the rake. I did some math to get enough rake travel to cover the garden from the servo’s 180 degrees of movement. The platform is just a scrap of fancy plywood. I popped the base off the lazy, susan and nailed down a couple blocks to hold it on one side. On the other side of the garden, i cut a hole in the platform and mounted the motor on a hinge with a rubber band to hold the wheel tight to the lazy susan. I glued the rake guide in place then mounted the servo. The servo is on an angled block to align its range of travel with the other parts.
The rake only has one tine made from 14 gauge copper wire slipped into a hole i drilled in the end of the rake handle. I don’t want to look at a display while meditating, but one might be useful for troubleshooting and setup. I put a character lcd and a piece of quarter inch syntra with the power switch to make room for the electronics.
Underneath i glued on a couple of feet. The electronics consist of an arduino, an lcd from adafruit, a blue smurf silver bluetooth, modem from sparkfun a battery box and switch from radio shack and a whole bunch of wire and connectors from pololu glue on edging will hide the plywood’s end grain and a coat of Danish oil will make it look nice. The programming is basic, just reading the data from the headset, with the bluetooth, modem and moving the rake servo back and forth the speed at which the rake moves is tied to the meditation value from the headset. If i’m not meditating well, the rake moves quickly and sporadically scribbling randomly in the sand, the deeper the meditation, the more theta waves my brain produces and the slower the rake moves. If i’m meditating quite deeply, the rake draws lovely spirals.
The human brain emits different types of waves, including alpha beta delta and theta theta waves. The ones used to set our meditation score have been linked to fantasy imagination and creativity. Have yourself a nice meditation, then go see what you can create. .
