If you want to find your inner peace... over and over again, this might be an interesting project for you :-). Of course it is more a fun project than really useful. I just had the idea of making something like this and the execution is a little bit crude, but it works.

Videolink

Things I needed to get this done:

Arduino (nano)
Servo
Breadboard and some wires
Soldering iron
Wooden bowl, box... etc.
Thin Plywood
Fine sand
and some household tools, nothing special

Step 1: Making the Lid

The box was flying around in our basement, so I just had to saw a lid from thin plywood. After I marked the center I drilled a hole and thinned the plywood a little bit to make more room for the servo. To complete this step, I just glued two pieces of scrap wood to the lid and screwed the servo onto the lid.

Step 2: Adding the Electronics

As for the arduino code I just took the example sweep code and added a delay at the beginning of the loop so that you have time to gain inner peace ;-).

For the power supply I took a 9v block and added it to a usb plug with a power switch in between, so that you can power up the "destruction feature" as you wish. For the cables to the servo I used some header terminals and soldered jumper wires to them so that the arduino can be easily taken out of the box. After everything was soldered I used some electrical tape to isolate everything.

Step 3: Making the Fork and Assembling the Box

As a tool for the micro zen garden you need some kind of fork. I made this out of scrap wood and three small nails. At first I just hammered the nails in but that made the wood split. So a pre-drilled the holes with my Dremel and that worked out fine.

A small piece of wire mesh was mounted onto the servo and so your sculpting will not last very long once the servo starts to turn ;-).

Thank you for reading and if you watch the video, you will see what this useless device does.