The Differential Analyzer
Abstract
The Differential Analyzer, so named in 1930 by its inventor, designer and builder, Dr. Vannevar Bush (then at the Massachusetts Institute of Technology), is a power driven machine for obtaining mechanically and printing in numerical tabular form the solution of any one of a wide variety of total differential equations. The machine at Aberdeen Proving Ground, adapted from the original (now obsolete) Differential Analyzer at Cambridge, Massachusetts, is officially "The Bush Differential Analyzer." The name "Differential Analyzer" was doubtlessly chosen because of the analogy which this name suggests, with the various well-known types of harmonic analyzers. However, this name has been thought by many to be somewhat of a misnomer. The machine parts perform as indicated below, beyond certain few restricted algebraic operations, only quadratures. Although this machine has the essential advantage over early types of planimeters and integraphs of being devised to accept as input for one part of the machine the output of another part, it does not "analyze differentials". It cannot even obtain the derivative of an arbitrarily given smoothly varying function. Save at most in one case, it will not (as now set up) multiply a given variable by a given constant unless this constant is, save for sign, the product of a small number of "simple rations". Because of the extraordinary flexibility of interconnections in the machine, and the theoretical possibility of adjoining one or more further "tables" if needed, other types of problems might be handled quite differently from those which now employ the full time of the machine. For theoretical purposes, the Differential Analyzer may be described as a group if independently operable submachines (each with fixed and movable parts) interconnected by rigid shafts or cable drives, the entire mechanical group being housed on a rigid steel frame. There are also electrical control elements with an elaborate separate panel board.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 23, 1942
- Accession Number
- ADA593830
Entities
People
- Albert A. Bennett
Organizations
- Ballistic Research Laboratory