»But does it run Linux?«

A clocked binary marble adder


2018 | Installation | Brass,  MDF, Arduino, Servos  |  55 x 35 x 96 cm


Concept

Computers are universal machines. With the input we give them they can do whatever we want them to. What is information to us, is nothing but signals to the machine: endless strings of ones and zeros whose meaning arises solely from our interpretation. A computer's only function is to process these signals an to apply mathematical and logical functions on them.


The most fundamental of all operations is the addition of two numbers, from which all others can be derived. This makes the simple addition of two numbers, executed millions of times a second in modern devices, one of the most important algorithms. But the processes inside these devices remain abstract and hardly graspable. This clocked mechanical adder transfers one of these hidden processes into human dimensions.



Version 2 at the 35th Chaos Communication Congress

The first version in action


How it works

The installation is the mechanical implementation of a serial adder logical circuit. Binary numbers are represented by marbles (glass meaning "one" and wood meaning "zero"). Hence both logical states are physically present and visible. A feature of the machine is its clock cycle that mimics the procedure of computers. The clock signal with the length of 13s is provided by three servos. At the beginning they open the inputs of all active components. All parts reset autonomously.  The whole logical circuit is executed mechanically; merely the clock signal is provided by a microcontroller.

 

For more information, have a look at the detailed documentation (in german).


Realisation

All components consist of soldered brass wire. Steel bolts form the framework that is mounted on medium density fibreboard. Currently, the installation is in its second version.



Logical composition:

1:  Two numbers are put into the input registers. With every clock cycle, the last bit is released.

2: The first half adder gives out the interim sum of the two input bits

3: Carry bits are saved in a one-bit-memory.

4: The second half adder gives out the sum of the interim sum and the carry bit.5: the result is given to the output register


Construction history: from sketch to prototype