A VLSI implementation of a fuzzy-inference engine: Toward an expert system on a chip

Abstract

We present a VLSI implementation of an inference mechanism to cope with uncertainty and to perform approximate reasoning. The design is based on the “max-min operation” of fuzzy set theory for effective and real-time use. This inference mechanism can handle imprecise and uncertain knowledge; therefore, it can obtain human expert knowledge and simulate reasoning processes. An inference mechanism has been realized by using custom CMOS technology which emphasizes simplicity, extensibility, and efficiency. Timing simulation suggests that the inference engine can perform approximately 80,000 fuzzy logical inferences per second. A potential application of such inference engines is real-time decision making in the area of command and control and adaptive command generation of robotic systems.