Sand Automata

Recently I did work on Automata. Sharing the same here.

Performance of this acrobat is powered by Sand. 

Many such old toys, driven by sand, always fascinated me. This is how I built one.

Instead of building a mechanism inside a rectangular box, I built this funnel and wheel from a cardsheet. This allowed me to test each step independently and make changes accordingly. 

Once I was happy with the movement of the acrobat, I placed this funnel inside a rectangular box and sealed it.

With a nice background picture, watching the performance of an acrobat was the best thing to happen.  Acrobat can perform for 30 seconds. To repeat this, I have to rotate the box clockwise to collect all the sand back in the funnel.

Now details about the build.

Cardsheet Funnel

Instead of building compartments in a box, an independent funnel is built with a cardsheet. This helps a lot in initial testing and finer adjustment. Triangle like shape is cut with each side - 15 cm. Sand will enter from this slot. A 6 cm extension on one side of the triangle will house the wheel. Large opening near the extension is sealed with paper with a small hole. 

Wheel

The Cardsheet wheel is made with a radius of 4 cm. 1 cm wide strips are pasted to form 8 small compartments. Toothpick acting as an axle is placed slightly off-center. This is important for two -way movement of the wheel. Larger wheel means more sand and hence acrobat can move full 

circle. 

Acrobat

Initially I made acrobat with PVC sheet, pins and blank refill. But this was heavy for the wheel I built. Hence I had to build another one with a thinner plastic sheet. 

Water instead of Sand

I tried using water instead of sand to power the acrobat. Wheel I designed was small. It could not move the acrobat as planned. 

Just  a Box

Initially, I built a mechanism in a used cardboard box. But testing and alignment was an issue. I also found that the weight of the acrobat was more for the wheel employed.

Tinkering

Try with other materials as well like these millets used in bird feeder. 

Enjoyed building sand automata. Sharing some versions which of course did not work to my satisfaction.

Thank You.