Patent US5574826A successfully refreshed from Google Patents.
US5574826A
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Memory organization method for a fuzzy logic controller and corresponding device
Assignee: STMicroelectronics SRL
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Filing: 1994-06-09
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Granted: 1996-11-12
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Expires: 2014-06-09
Abstract
Abstract A method for setting up the memory of an electronic controller operates using fuzzy logic, whereby predetermined membership functions f(m) of logic variables M, defined within a universe of discourse sampled in a finite number of points m, are subjected to inference operations basically configured by IF/THEN rules with at least one front preposition and at least one rear implication. The controller includes a central control unit provided with a memory section for storing predetermined values of the membership functions f(m) which appear in the front or IF part of the fuzzy rules and have a predetermined degree of truth or membership. This method provides for storing into the memory section only the values of those membership functions f(m) which have a value of the degree of membership other than zero at the points m of the universe of discourse.
Inventors
- 👤 Biagio Russo
- 👤 Claudio Luzzi
- 👤 Rinaldo Poluzzi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:43
CPC Classifications
G; G06; G06F; G06F1/00; G06F1/02; G06F1/03; G06F1/035; G05; G05B; G05B13/00; G05B13/02; G05B13/0265; G05B13/0275; G06N; G06N7/00; G06N7/02; G06N7/04; Y; Y10; Y10S; Y10S706/00; Y10S706/90
Claims Analysis
Total Claims: 49
Claim 1
Independent Claim
111 words
A method for loading information into a memory section of an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a number of membership functions are defined for a finite number of points within a universe of discourse, the method comprising the steps of: providing values of the membership functions appearing in the preposition of at least one of the rules, each value being indicative of a degree of membership; and storing in the memory section, for each of the finite number of points, the values of only those membership functions for the point which are not zero.
Claim 2
Independent Claim
111 words
A method for loading information into a memory section of an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a number of membership functions are defined for a finite number of points within a universe of discourse, the method comprising the steps of: providing values of the membership functions appearing in the preposition of at least one of the rules, each value being indicative of a degree of membership; and storing in the memory section, for each of the finite number of points, the values of only those membership functions for the point which are not zero.
Claim 3
Dependent Claim
56 words
The method of claim 1, further comprising the step of determining which of the finite number of points has a largest number of non-zero values, and wherein the step of storing includes storing a memory word in the memory section, wherein a length of the memory word is dependent on the largest number of non-zero values.
Claim 4
Dependent Claim
61 words
The method of claim 2, further comprising the step of determining the length L of the memory word such that L=nf(m)*(dim(G)+dim(f(m)), where nf(m) is the largest number of non-zero values, dim(G) is a word size required to represent a value indicative of a degree of membership, and dim(f(m)) is a word size required to represent the number of the membership functions.
Claim 5
Dependent Claim
18 words
The method of claim 3, wherein the largest number of non-zero values is between one to five, inclusive.
Claim 6
Dependent Claim
14 words
The method of claim 4, wherein the largest number of non-zero values is three.
Claim 7
Dependent Claim
44 words
The method of claim 1, wherein the step of storing comprises storing, for each point in the finite number of points, a memory word comprising an indication of each of the membership functions with a non-zero value for the point and the non-zero value.
Claim 8
Dependent Claim
45 words
The method of claim 6, wherein the step of storing a memory word for a point comprises the step of storing the memory word for the point such that the memory word is retrievable by applying an indication of the point to the memory section.
Claim 9
Dependent Claim
136 words
An electronic controller, comprising: a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions; and a memory section for storing values of the membership functions wherein the memory section has a size defined by a number of nonzero values of the membership functions associated with a selected one of the finite number of points, the selected point having the largest number of nonzero values.
Claim 10
Dependent Claim
136 words
An electronic controller, comprising: a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions; and a memory section for storing values of the membership functions wherein the memory section has a size defined by a number of nonzero values of the membership functions associated with a selected one of the finite number of points, the selected point having the largest number of nonzero values.
Claim 11
Dependent Claim
27 words
The electronic controller of claim 8, wherein a length L of a memory word of the memory section is dependent on the largest number of non-zero values.
Claim 12
Dependent Claim
56 words
The electronic controller of claim 9, wherein the length L of the memory word is L=nf(m)*(dim(G)+dim(f(m)), where nf(m) is the largest number of non-zero values, dim(G) is a word size required to represent a value indicative of a degree of membership, and dim(f(m)) is a word size required to represent the number of the membership functions.
Claim 13
Dependent Claim
20 words
The electronic controller of claim 9 or 10, wherein the number of non-zero values is between one to five, inclusive.
Claim 14
Dependent Claim
14 words
The electronic controller of claim 11, wherein the number of non-zero values is three.
Claim 15
Dependent Claim
125 words
An electronic controller, comprising: a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions; and a memory section for storing values of the membership functions wherein the memory section stores, for each point of the finite number of points, the values of only those membership functions of the point which are not zero.
Claim 16
Dependent Claim
125 words
An electronic controller, comprising: a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions; and a memory section for storing values of the membership functions wherein the memory section stores, for each point of the finite number of points, the values of only those membership functions of the point which are not zero.
Claim 17
Dependent Claim
40 words
The electronic controller of claim 13, wherein the memory section stores, for each point of the finite number of points, a memory word comprising an indication of the membership functions with non-zero values for the point and the non-zero values.
Claim 18
Dependent Claim
40 words
The electronic controller of claim 14, wherein the memory word for the point is stored in the memory section such that the memory word is retrievable by applying an indication of the point to an input of the memory section.
Claim 19
Dependent Claim
29 words
The electronic controller of claim 13, wherein the memory section has a size defined by one of the finite numbers of points having a largest number of non-zero values.
Claim 20
Dependent Claim
27 words
The electronic controller of claim 16, wherein a length L of a memory word of the memory section is dependent on the largest number of non-zero values.
Claim 21
Dependent Claim
56 words
The electronic controller of claim 17, wherein the length L of the memory word is L=nf(m)*(dim(G)+dim(f(m)), where nf(m) is the largest number of non-zero values, dim(G) is a word size required to represent a value indicative of a degree of membership, and dim(f(m)) is a word size required to represent the number of the membership functions.
Claim 22
Dependent Claim
21 words
The electronic controller of claim 17 or 18, wherein the largest number of non-zero values is between one to five, inclusive.
Claim 23
Dependent Claim
15 words
The electronic controller of claim 19, wherein the largest number of non-zero values is three.
Claim 24
Dependent Claim
104 words
A memory section for an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a membership function, defined for a finite number of points of a universe of discourse, appears in the preposition of at least one of the rules, the membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, wherein the memory section stores for each point of the finite number of points the values of only those membership functions for the point which are not zero.
Claim 25
Dependent Claim
104 words
A memory section for an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a membership function, defined for a finite number of points of a universe of discourse, appears in the preposition of at least one of the rules, the membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, wherein the memory section stores for each point of the finite number of points the values of only those membership functions for the point which are not zero.
Claim 26
Dependent Claim
38 words
The memory section of claim 21 which stores, for each point of the finite number of points, a memory word comprising an indication of the membership functions with non-zero values for the point and the corresponding non-zero values.
Claim 27
Dependent Claim
36 words
The memory section of claim 22, wherein the memory word for the point is stored such that the memory word is retrievable by applying an indication of the point to an input of the memory section.
Claim 28
Dependent Claim
26 words
The memory section of claim 21 having a size defined by which point of the finite numbers of points has a largest number of non-zero values.
Claim 29
Dependent Claim
27 words
The memory section of claim 24, wherein a length L of a memory word of the memory section is dependent on the largest number of non-zero values.
Claim 30
Dependent Claim
56 words
The memory section of claim 25, wherein the length L of the memory word is L=nf(m)*(dim(G)+dim(f(m)), where nf(m) is the largest number of non-zero values, dim(G) is a word size required to represent a value indicative of a degree of membership, and dim(f(m)) is a word size required to represent the number of the membership functions.
Claim 31
Dependent Claim
21 words
The memory section of claim 25 or 26, wherein the largest number of non-zero values is between one to five, inclusive.
Claim 32
Dependent Claim
15 words
The memory section of claim 27, wherein the largest number of non-zero values is three.
Claim 33
Dependent Claim
115 words
A memory section for an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a membership function, defined for a finite number of points of a universe of discourse, appears in the preposition of at least one of the rules, the membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, wherein the memory section has a size defined by a number of nonzero values of the membership functions associated with a selected one of the finite number of points, the selected point having the largest number of nonzero values.
Claim 34
Dependent Claim
115 words
A memory section for an electronic controller which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a membership function, defined for a finite number of points of a universe of discourse, appears in the preposition of at least one of the rules, the membership function having a value for each of the finite number of points, which value is indicative of a degree of membership, wherein the memory section has a size defined by a number of nonzero values of the membership functions associated with a selected one of the finite number of points, the selected point having the largest number of nonzero values.
Claim 35
Dependent Claim
27 words
The memory section of claim 29, wherein a length L of a memory word of the memory section is dependent on the largest number of non-zero values.
Claim 36
Dependent Claim
56 words
The memory section of claim 30, wherein the length L of the memory word is L=nf(m)*(dim(G)+dim(f(m)), where nf(m) is the largest number of non-zero values, dim(G) is a word size required to represent a value indicative of a degree of membership, and dim(f(m)) is a word size required to represent the number of the membership functions.
Claim 37
Dependent Claim
20 words
The memory section of claim 30 or 31, wherein the number of non-zero values is between one to five, inclusive.
Claim 38
Dependent Claim
14 words
The memory section of claim 32, wherein the number of non-zero values is three.
Claim 39
Independent Claim
213 words
A method for using an electronic controller which includes a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a corresponding value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions, and a memory section for storing predetermined values of the membership functions wherein the memory section stores, for each of the finite number of points, an indication of and the value corresponding to only those membership functions for which the degree of membership of the point is not zero, the method comprising the steps of: receiving an input indicative of one of the finite number of points; obtaining from the memory the predetermined non-zero values of the membership functions for the received point and identities of corresponding membership functions; selecting a membership function; and restoring effective values of the membership functions from the obtained non-zero values and identities to extract predetermined weights involved in the rules which configure the inference operations.
Claim 40
Independent Claim
213 words
A method for using an electronic controller which includes a central control unit which performs inference operations according to rules, each rule comprising at least one preposition and at least one implication, wherein a plurality of membership functions are defined for a finite number of points of a universe of discourse, each membership function having a corresponding value for each of the finite number of points, which value is indicative of a degree of membership, and wherein at least one of the rules has a preposition including one of the membership functions, and a memory section for storing predetermined values of the membership functions wherein the memory section stores, for each of the finite number of points, an indication of and the value corresponding to only those membership functions for which the degree of membership of the point is not zero, the method comprising the steps of: receiving an input indicative of one of the finite number of points; obtaining from the memory the predetermined non-zero values of the membership functions for the received point and identities of corresponding membership functions; selecting a membership function; and restoring effective values of the membership functions from the obtained non-zero values and identities to extract predetermined weights involved in the rules which configure the inference operations.
Claim 41
Dependent Claim
49 words
The method of claim 34, wherein the step of restoring comprises the steps of: comparing the selected membership function to the indications of the membership functions stored for the received point; and outputting zero when an indication of the selected membership function is not stored for the received point.
Claim 42
Dependent Claim
64 words
The method of claim 34, wherein the step of restoring comprises a step of comparing bits of a part (w(f(m) i )) of the memory word output from the memory section related to the membership functions (f(m) i ) with bits of a reference word (w(f rif )) contained in a program memory in which the rules which configure the inference operations are stored.
Claim 43
Dependent Claim
82 words
The method of claim 36, wherein the step of comparing said part (w(f(m) i )) of the memory word output from the memory section with bits of said reference word (w(f rif )) from said program memory obeys the following logic relationship: if w(f.sub.rif)=w(f(m).sub.i) then weight=value 1.sub.f(m)i, and if w(f.sub.rif)≠w(f(m).sub.i) then weight=0, wherein weight is a value selected during the step of restoring, and 1 f (m)i is a value corresponding to an i-th membership function where i is a non-negative integer.
Claim 44
Dependent Claim
108 words
An electronic controller, comprising: means for receiving an input which indicates one of a finite number of points; a memory section for storing predetermined values of the membership functions wherein the memory section stores, for each of the finite number of points, an indication of and the value of only those membership functions for which the degree of membership of the point is not zero; a calculating section for performing the fuzzy logic inference operations; and a buffer section, between the memory section and the calculating section, for regenerating effective values of the membership functions to extract predetermined weights involved in the rules which configure the inference operations.
Claim 45
Dependent Claim
108 words
An electronic controller, comprising: means for receiving an input which indicates one of a finite number of points; a memory section for storing predetermined values of the membership functions wherein the memory section stores, for each of the finite number of points, an indication of and the value of only those membership functions for which the degree of membership of the point is not zero; a calculating section for performing the fuzzy logic inference operations; and a buffer section, between the memory section and the calculating section, for regenerating effective values of the membership functions to extract predetermined weights involved in the rules which configure the inference operations.
Claim 46
Dependent Claim
88 words
The electronic control device of claim 38, wherein the buffer section comprises a comparator having a first input for receiving an indication of a selected membership function from the central control unit and a second input connected to the output of the memory for receiving the indications of and the values of membership functions stored for the point indicated by the means for receiving and having an output which provides a zero output when the selected membership function is not indicated by the indications received from the memory.
Claim 47
Dependent Claim
71 words
An electronic control device of claim 38, wherein the buffer section comprises a program memory, in which all the rules for the inference operations are stored, and having an output indicative of a membership function; and a comparator, for comparing bits of a part of the memory word output from the memory section and related to the membership functions, with bits of a reference memory word contained in the program memory.
Claim 48
Dependent Claim
28 words
The electronic control device of claim 40, wherein the comparator is connected to the program memory through a micro-encoder which selects the reference words within the program memory.
Claim 49
Dependent Claim
34 words
The electronic control device of claim 40, wherein the comparator has inputs connected to respective outputs of the memory section and the program memory, and is connected to the input of the calculating section.
References Cited (Backward Citations)
US5287432A
Cited
JPH04100153A
Cited
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| 7.5 Years (Year 8) | 2003-11-12 | 2004-05-13 | 2004-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-11-12 | 2008-05-13 | 2008-11-12 | $7700.00 | Window Closed / Lapsed |