Abstract

Lee A. Rubel defined the extended analog computer to remove the limitations of Shannon’s general purpose analog computer. Partial differential equation solvers were a “quintessential ” part of Rubel’s theoretical machine. These components have been implemented with “empty space ” (VLSI circuits without transistors), as well as conductive plastic. For the past decade research at Indiana University has explored the design and applications of extended analog computers. The machines have become increasingly sophisticated and flexible. The “empty ” computational area solves partial differential equations. The rest of the space includes fuzzy logic elements, configuration memory and input/output channels. This paper describes the theoretical definition, architecture and implementation of these unconventional computers. Two applications are described in detail. Rubel’s model can be viewed as an abstract specification for a distributed supercomputer. We close with a description of this inexpensive 64-node supercomputer that is based on our current single processor, and which has been placed into the public domain. The next step is to implement the improved architecture in VLSI, and seek computation speeds approaching trillions of partial differential equations per second.

Citations