Appliance electronic control system with programmable and reconfigurable fuzzy logic controller

An appliance electronic control system for controlling at least a washing machine appliance having a tub which is filled to a predetermined water volume during operation and having a plurality of functional elements for implementing a plurality of appliance functions, said appliance electronic control system comprising:

• an element for comparing a signal representing water volume to a predetermined water volume and discontinuing a water filling operation when the tub is filed to the predetermined water volume;
• a fuzzy logic controller including:
• at least one input for receiving an input value;
• an output;
• a configuration input for receiving definitions of at least one set of input membership functions corresponding to said at least one input, definitions of a set of output membership functions, and a set of inferencing rules each defined as a plurality of control bits;
• memory elements for storing input membership function definitions, output membership function definitions and inferencing rules;
• updating elements connected to said configuration input and to said memory elements for updating membership functions and inferencing rules in said memory elements while inferencing rules are being processed during operation of the fuzzy logic controller;
• elements for calculating a degree of belief for each of the stored input membership functions based on the input value;
• an inference engine operable, for each of the stored set of inferencing rules, to calculate a scaled value for a particular output membership function based on at least one input membership function degree of belief in accordance with control bits of the inferencing rule;
• and
• elements for calculating a crisp value based on the calculated scaled values and for outputting the crisp value to said output;
• and
• an element for supplying a pressure reading to said reconfigurable fuzzy logic controller as an input, the pressure reading representing water pressure at the bottom of the washing machine tub;
• wherein said fuzzy logic controller is programmed to provide, as an output, the signal representing water volume for use by said element for discontinuing a water filling operation.

An appliance electronic control system for controlling at least a clothes drying appliance having a plurality of functional elements including a duty cycle controlled heating element for implementing a plurality of appliance functions, said appliance electronic control system comprising:

• a control element for the duty cycle controlled heating element;
• a fuzzy logic controller including:
• at least one input for receiving an input value;
• an output;
• a configuration input for receiving definitions of at least one set of input membership functions corresponding to said at least one input, definitions of a set of output membership functions, and a set of inferencing rules each defined as a plurality of control bits;
• memory elements for storing input membership function definitions, output membership function definitions and inferencing rules;
• updating elements connected to said configuration input and to said memory elements for updating membership functions and inferencing rules in said memory elements while inferencing rules are being processed during operation of the fuzzy logic controller;
• elements for calculating a degree of belief for each of the stored input membership functions based on the input value;
• an inference engine operable, for each of the stored set of inferencing rules, to calculate a scaled value for a particular output membership function based on at least one input membership function degree of belief in accordance with control bits of the inferencing rule;
• and
• elements for calculating a crisp value based on the calculated scaled values and for outputting the crisp value to said output;
• and
• elements for supplying an air temperature error signal and a rate of change of air temperature error signal to said fuzzy logic controller as inputs, the air temperature error signal representing the difference between measured air temperature within the clothes drying appliance during operation and a predetermined drying temperature;
• wherein said fuzzy logic controller is programmed to provide, as an output, a signal for controlling the duty cycle of said heating element.