A functioning Turing Machine

Mike Davey from Wisconsin, who describes himself as someone who “always liked to make things”, has created a fully functioning Turing machine. Many computer scientists such as myself went through at least one class where we had to learn about the theoretical intricacies of Turing’s manifestation of a computable (mathematical) function – tape, symbols, reading, writing, erasing, alphabets, halting states and so on. Well that all would have been a lot more concrete and interesting with Mr. Davey’s device at hand, shown below

 

Please visit his site, the aptly named aturingmachine.com, to see a video of the machine in action. The device is driven by a microprocessor but the “computations” - moving the tape and changing its contents under the “head” - are quite faithful to Turing’s description. The tape is not infinite but rather 1000 foot roll of white 35mm film, where binary characters can be read, written and erased. Mr. Davey says he is not deeply attached to his creation, and may be willing to part with it in a year or so.