Fuzzy control apparatus in which rules can be changed, method of

Details Fuzzy control apparatus in which rules can be changed, method of Fuzzy control apparatus in which rules can be changed, method of

1991-12-13

1996-05-07

Moore, David K.

395900, 395 61, G06F 1518, G06G 700

Patent

active

055154760

DESCRIPTION:

BRIEF SUMMARY
DESCRIPTION

1. Technical Field
This invention relates to a fuzzy control apparatus, and to a method of operating the same, in which rules are capable of being changed during execution (operation) of fuzzy reasoning. The invention relates also to a system having a plurality of control apparatus for controlling one controlled object, especially a control system in which a changeover can be made among a plurality of control apparatus by fuzzy reasoning, and to a method of controlling this system.
2. Background Art
A fuzzy control apparatus is provided with an input of a controlled variable from a controlled object, executes so-called modus ponens reasoning, and outputs a manipulated variable (a fuzzy-control output) to be applied to the controlled object. Fuzzy reasoning often is expressed by control rules ("If . . . , then . . . " rules) in an "If . . . , then . . . " format.
A fuzzy control apparatus is available in which the control rules can be changed by a manual or remote operation during execution (operation) of fuzzy reasoning. In a fuzzy control apparatus of this kind, there is the possibility that the fuzzy-control output will vary suddenly according to the content of a changed rule. When a fuzzy-control output undergoes a sudden change, there is the danger that the controlled object will be adversely affected.
In order to deal appropriately with a controlled object having a characteristic that differs depending upon state, and in order to raise the accuracy of control, a system which controls one controlled object by using a plurality of control apparatus has been proposed. In a control-system of this kind, which control apparatus among the plurality thereof is to be given charge of controlling the controlled object is decided using an arithmetic expression that is expressed arithmetically, and a changeover is performed manually by an attendant.
However, in accordance with the arithmetic decision regarding the control apparatus to be put in charge and the changeover based upon this decision, it is difficult to arithmetically express, in accurate fashion, the timing at which the control apparatus is changed over, and to evaluate the timing. In addition, it is difficult to perform a highly accurate changeover.
Further, in a manual changeover performed by an attendant, a problem which arises is that reproducibility of changeover timing is poor and a variance develops in the results of control. For example, in a case where the operation of a moving object is controlled, a problem encountered is that smooth control of operation cannot be carried out. In addition, in a case where the manufacturing process of an article is controlled, a variance develops in the quality of the articles manufactured. Disclosure of the Invention
An object of the present invention is to provide a fuzzy control apparatus, and a method of operating the same, in which a fuzzy-control output can be varied smoothly even in a case where a rule is changed during operation.
Another object of the present invention is to provide a fuzzy control apparatus and a method of operating the same, in which a rule is capable of being changed only under a condition that a control output may not be suddenly varied.
Still another object of the present invention is to provide a control system and a control method in which the changeover among a plurality of control apparatus for controlling one controlled object can be performed appropriately at all times.
A fuzzy control apparatus in which a rule can be changed in accordance with the present invention is characterized by having fuzzy reasoning means in which a rule is capable of being changed during operation, means for storing a fuzzy reasoning output which prevails immediately prior to a rule change, synthesizing output means for combining, and outputting as a fuzzy-control output, the stored fuzzy reasoning output which prevailed immediately prior to the rule change and a fuzzy reasoning output which prevails following the rule change, and means for altering a combining ratio of the synthesizi

REFERENCES:
patent: 4864490 (1989-09-01), Nomoto et al.
patent: 4976377 (1990-12-01), Higuchi et al.
patent: 5051932 (1991-09-01), Inoue et al.
patent: 5079704 (1992-01-01), Sakai et al.
patent: 5084754 (1992-01-01), Tomitaka
patent: 5167005 (1992-11-01), Yamakawa
patent: 5168549 (1992-12-01), Takagi et al.
patent: 5175795 (1992-12-01), Tsuda et al.
Nikkei Electronics, Jul. 27, 1987, pp. 148-152, published by Nikkei McGraw-Hill.

Affiliated with

Also associated with

Rating

Fuzzy control apparatus in which rules can be changed, method of does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fuzzy control apparatus in which rules can be changed, method of, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuzzy control apparatus in which rules can be changed, method of will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1233966