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Additional CAD components

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I am using autocad fusion 360 to model additional components.

Here is an animated model of a switch:
  And this one is a bit more complicated, a 'stop': Ryan 3D printed some of the base components for me. Here is the main piece of the 'stop'.
The part is so small that the channels are not very clean. Ryan also said he wouldn't be able to get great resolution on the 1 mm thick moving part. He suggested that we use his CNC to mill them out of wood or plastic instead.

I think my initial design of the 'stop' is too complicated. It would also be nice if all the components would lie flat on a board. My friend Justin drew a picture on a white board that showed a trigger to stop and release marbles. Here, a marble gets stopped on the left channel until a marble comes down the right and hits the trigger, releasing the marble on the left.



I also think I would like to use some micro bearings and maybe machine the moving parts out of aluminum. Also I have been doing so…

Marble Separator Prototype

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He is ready to separate the chaff from the wheat with his winnowing fork. - Mathew 3:12

I like to define the ones as wheat and the zeros as chaff. I need to build a winnowing fork to separate the marbles for operations like sorting. I have a couple of landscaping pitchforks in the garage with tines the perfect distance to separate 'shooters' from 'cats-eyes', but they are way too big to go into a computer and I need them to spread wood chips.

Recall that we defined a separator as a component that takes in a marble and routes it one direction if it is a large marble (wheat) and routes it another direction if it is a small marble (chaff).

Here is a youtube video of my first separator made with popsicle sticks and glue:


Eureka! I've done it! This is the first of my components to build my marble computer!! And it's pretty small, only about 3x2x6 = 36 cubic inches. With only 8 components in an AND gate, an average gate might be 288 in^3. Then a full adder with 9 g…

Marble AND gate description

We can use the language defined in the previous post to describe a marble AND gate. Where i1 and i2 are the inputs, o1 is the output, and X is dumped into a marble recycling bin.

i1     i2   Two marbles are dropped into two channels, maybe not at the same time.
    Y        The two channels narrow into one.
   12       A switch sends the first marble to the left
    -|        Where it is stopped until the second marble comes through
    Y       Now the marbles are nearly time synchronized and narrow into a single channel
   //\        Where they are separated big from small
  Z  |       Any big marbles are delayed, ensuring that if there is a small marble, it goes first
   Y        Then back into a single channel
   12       The first marble goes to the left output and the second one is dumped
o1   X

So this device waits until both inputs have come in and then slows down any big marbles, ensuring that if there is a small marble it will be output and the other marble will be dumped. …

Marble Computer Language

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In symbols one observes an advantage in discovery which is greatest when they express the exact nature of a thing briefly and, as it were, picture it; then indeed the labor of thought is wonderfully diminished.  - Liebniz

To build an AND gate, we need some smaller components. We also need a language to talk about the smaller components.

1. Consider a marble run component with one input track and two output tracks. If a big marble is put into the input track, it comes out on the left output track. If a small marble is put into the input track, it comes out on the left hand track.

We call this component a Separator. We use the following symbol, an inverted Y with a double hash to denote which side the big marble comes out:
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//\

2. Consider a marble run component with one input track and one output track. The marble going into the input track comes out of the output track but is delayed.

We call this component a Delay with the symbol:
Z

3. Consider a marble run component with one in…

Marble AND Gate definition

According to wikipedia: 'Walther Bothe, inventor of the coincidence circuit, got part of the 1954 Nobel Prize in physics, for the first modern electronic AND gate in 1924'

Well, lets try to trivialize his incredible contribution to the scientific achievement of mankind by trying to repeat his feat with dollar store marbles, popsicle sticks, and glue.

Lets start by defining a marble AND gate. We begin by defining a large marble to be a true, and a small marble to be a false. Then a marble and gate will take in 2 inputs and produce 1 output. We can produce a table of inputs and outputs as:

i1 i2 output
o o   o
o O  o
O o  o
O O O

Any marble machine that corresponds to the above table is an AND gate!

Initial Musings

I want to build a computer out of marbles.

I told a few people about this plan and they look at me like I am crazy.

What do I mean by making a computer out of marbles?

Modern digital computers take in instructions called 'programs' and execute them by running electricity through specialized gates. The results are then usually either returned or stored. Instead of running electricity through electronic gates, I intend to run marbles through mechanical gates using gravity to the same end (albeit slower and smaller).

The 'DigiComp II' and the 'Rule 110' marble computers are already built, but I will be doing something a bit different than those and other marble computers I've seen. My computer will use 2 different sized marbles for 1's and 0's and not store all information in the marbles themselves rather than the state of the machine.