Friday, September 20, 2019

Autumn 2019 report to the Computer Conservation Society

This was presented by Doron Swade on September 19, 2019 to the Computer Conservation Society

In a visit from the US in March Tim Robinson reviewed a collection of ‘mystery’ material consisting of content that had eluded listing or cataloguing in earlier programmes by the Science Museum, and by Allan Bromley who produced, in 1991, the first near-comprehensive listing of the Babbage technical archive.  Logging this last cache of material is now complete and it appears that only about a third of the original material survives. This estimate is based on references in the Sketchbooks to material that should be in this cache but were not found there, or elsewhere. Findings have been shared with Science Museum archivists accompanied by suggestions of how this material might fit into the structure of the new Babbage catalogue, available now online, created by the Science Museum. There is material in the Buxton archive in Oxford that awaits attention but the primary technical archive of Babbage papers held by the Science Museum has now been viewed and relevance to the AE design logged.

With the archive review essentially complete, a process that took over three years, Tim has shifted attention to developing a simulation environment to describe, explore, and verify the mechanical designs. So far this involves ‘logical’ simulation which features aspects of Babbage’s Mechanical Notation, the language of signs and symbols he devised to describe the machines and as a design aid, not unlike a later Hardware Description Language (HDL). Features of the Mechanical Notation that are reflected in the simulation tools include the notion of a ‘piece’ (an aggregation of parts that acts or is acted on as an ensemble), ‘working points’ (the points of influence and action between pieces), ‘assemblies’ and ‘connections’. It is hoped that this high-level simulation will be extended in due course to solid modelling and techniques for visualisation as a design aid, a manufacturing front-end, and for education.

Doron Swade