Abstract

An arrangement (apparatus and method) using fuzzy logic controls a plurality of devices in response to inputs. The time-division-multiplexed input signals are demultiplexed and fuzzified according to predetermined fuzzy sets. Each crisp input is fuzzified by determining the distance of the crisp input from a center of the membership function of the fuzzy set and linearly complementing the result with respect to the width of the membership function, thereby eliminating the necessity for determining the shape of the membership function. The center may be a fixed value or a "floating" input. The fuzzified input signals are input to an asynchronous multipath feedforward network which determines a minimum rule term for each rule processed. The multipath feedforward network is dedicated to process the fuzzified input signals in parallel and to determine the minimum rule term using a minimum amount of circuitry. A maximum comparator circuit compares the minimum rule term of each rule corresponding to an output in order to determine the rule which provides the optimum output in response to the fuzzified inputs. An output register defuzzifies the output signal, time-division-multiplexes the output signals, provides feedback to the fuzzifier, and outputs the multiplexed output signals to the devices to be controlled. Other features include a timing generator which minimizes cycle times, a timer processor which provides time-variable inputs, and a keyboard controller.

Other References

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