Digital fuzzy inference system using logic circuits

U.S. Patent Number: 5343553

Abstract: A digital fuzzy inference system has fuzzy inference processors each of which is provided for each of fuzzy rules and comprises if-part membership function defining circuits, a minimum-value calculation circuit and a then-part membership function defining circuit. Each of if-part inputs is supplied to a corresponding if-part membership function defining circuit in which the if-part membership function is defined in accordance with definition parameters and the membership value is calculated by referring to the defined membership function and the input value. For each of the rules, membership values are entered into the minimum-value calculation circuit to select their minimum value. The minimum value is applied to the then-part membership function defining circuit which defines a then-part membership function in accordance with definition parameters and a then-part input. Then-part membership functions for all the rules are synthesized through maximum-value calculation by a membership function synthesizing circuit. The result of synthesis serves as a fuzzy inferential result. For a fuzzy controller for controlling a controlled object in accordance with the inferential result, the center-of-gravity calculation circuit calculates a value of the center of gravity from the synthesized membership function because the inferential result needs one definite value.

Inventors: Miyazawa; Azuma (Mitaka, JP), Suzuki; Takashi (Hachioji, JP), Mizobuchi; Kozi (Hachioji, JP)

Assignee: Olympus Optical Co., Ltd. (Tokyo, JP)

Application Number: 08/018,465

Issued: 1994-08-30

Expired: 2006-08-30

Classes: 706/4 ; 706/900

Field of search: 395/3,61,900

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