Method and apparatus for cooperated design

• US 5,572,430 A
• Filed: 06/29/1992
• Issued: 11/05/1996
• Est. Priority Date: 07/03/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Nishi, Kunihiko, Imanishi, Hiroko, Kazuhiro, Sugino, Saeki, Junichi, Akasaka, Shingo
• Primary Examiner(s): Envall, Jr., Roy N.
• Assistant Examiner(s): OAKES, BRIAN
• Application Number:
  US07/905,888
• Time in Patent Office: 1,590 Days
• Field of Search: 364/468, 364/490, 364/491, 364/150, 364/148, 364/149, 364/151, 364/401
• US Class Current: 700/95
• CPC Class Codes: G06F 30/00 Computer-aided design [CAD]

Abstract

In order to derive optimum design specifications based on total evaluation performed on a product as a whole instead of individual design items during a process of determining design specifications involving a plurality of design items, candidates for the product specifications are selected by controlling design parameters for each of the design items in an integrated manner, computing values of a plurality of evaluation items evaluating candidates for the design specifications and performing total evaluation on all the evaluation items based on their computed values through collaboration among a plurality of design sections altogether auto-correcting all relevant design parameters quickly and relaxing as well as reassessing design constraints for a design parameter.

Claims

1. A collaborated design management method for supporting a process of determining specifications comprised of design parameters of a product during a design process involving a plurality of design sections or prototyping sections, said method comprising:

a first step of inputting into a computer system design parameters of a product-specification draft including at least external dimensions, materials and manufacturing conditions which are input at each design section with constraint conditions for each design parameter related to said product as well as set base data or empirical data for said constraint conditions, rules governing relations among said design parameters and a set of programs necessary for evaluation of said design parameters registered in advance;

a second step of autonomously correcting all design parameters or setting all design parameters affected by updating of a design parameter or inputting of a new design parameter;

a third step of judging whether values of said corrected design parameters meet said constraint conditions;

a fourth step of computing and displaying to a user a difference between a value of a design parameter and a constraint value in the case of a detected constraint violation by said design parameters;

a fifth step of requesting the user to correct an inputted value of said design parameter or to modify said constraint condition in the case of the detected constraint violation by said design parameter;

a sixth step of creating a list of constraint conditions related to said design parameter which violate said constraint along with set base data of said conditions and displaying said list to the user in case the user has selected an alternative to modify said constraint values;

a seventh step of re-cataloging said displayed constraint conditions after being corrected interactively, whereby all relevant design parameters are corrected automatically through collaboration among a plurality of design sections whenever a local design parameter is changed by an individual design section; and

constructing the product in accordance with the corrected relevant design parameters.

2. A computer-assisted collaborated design management system for supporting a process of determining specifications comprised of design parameters of a product during a design process involving a plurality of design sections or prototyping sections, said system comprising:

data input means for inputting into a computer system design parameters of a product-specification draft including at least external dimensions, materials and manufacturing conditions inputted at each of said design sections and prototyping sections;

design-parameter management means for controlling all design parameters for a product in an integrated manner;

design-constraint registration means for cataloging constraint conditions for each design parameter along with set base data for constraint conditions;

program registration means for cataloging rules governing relations among said design parameters or a set of programs required for computing values by said computer system of evaluation functions for said design parameters;

design-consistency management means comprising a function for loading and invoking relevant programs from said program registration means accompanying modification of a design parameter and automatically correcting all design parameters affected by the modification of said design parameter, and a function for checking whether corrected values of said design parameters meet constraint conditions cataloged in said design constraint registration means; and

constraint-relaxation and adjustment means comprising a function for listing and displaying constraint conditions in said design-constraint registration means not satisfied by design parameters in question, and a function for interactively correcting said unsatisfied design constraints and recataloging said corrected design constraints into said design-constraint registration means.

3. A computer-assisted collaborated design management network system for supporting determination of specifications comprised of design parameters of a product in a distributed design process involving a plurality of design sections and prototyping sections located at sites remote from each other, said collaborated design/development management network system comprising workstations each installed at one of said design sections and said prototyping sections and connected to each other to form a network, wherein each of said workstations serves as a collaborated design management apparatus comprising at least:

data-input means for inputting design parameters into a computer system of a product-specification draft including at least external dimensions, materials and manufacturing conditions inputted by the user;

design-parameter management means for controlling all design parameters for a product in an integrated manner;

design-constraint registration means for cataloging constraint conditions for each design parameter along with set base data for said constraint conditions;

program registration means or cataloging rules governing relations among said design parameters or a set of programs required for computing values of evaluation functions for said design parameters;

design-consistency management means comprising a function for loading and invoking relevant programs from said program registration means accompanying modification of a design parameter and automatically correcting all design parameters affected by the modification of said design parameter, and a function for checking whether or not corrected values of said design parameters meet constraint conditions cataloged in said design-constraint registration means; and

constraint-relaxation and adjustment means comprising a function for listing and displaying constraint conditions in said design-constraint registration means not satisfied by design parameters in question, and a function for interactively correcting said unsatisfied design constraints and recataloging said corrected design constraints into said design-constraint registration means.

4. A method for computer-assisted cooperative design for use by a plurality of design departments in cooperatively determining design specifications of a product having a plurality of design items, said method including a process of supporting computer data input and a process of supporting cooperative design, said process of computer data input comprising the steps of:

(a) inputting into a computer system, via an input unit, the names of the design parameters for determining the design specifications of said product in conjunction with the name of the design department having the right to determine the values of said design parameters as well as the information about whether or not any of the design parameters is associated with a trade-off among a plurality of design evaluation items, the input names and the input information being stored into a design parameter management part of a storage unit of the computer system; and

(b) inputting, via said input unit, an analysis program for each of said design evaluation items in conjunction with the design parameters needed to perform said analysis program, the input analysis program and the input design parameters being stored into an analysis program storage part of said storage unit;

said process of supporting cooperative design comprising the steps of;

(c) inputting via said input unit the values of the design parameters which a given design department has the right to determine, together with any design evaluation items needed in conjunction with said design parameters;

(d) storing the input design parameter values into said design parameter management part of said storage unit;

(e) if any design evaluation item was input in the step (c), autonomously retrieving the analysis program corresponding to the input design evaluation item from said analysis program storage part of said storage unit and, if no design evaluation item was input in the step (c), retrieving from said analysis program storage part of said storage unit the analysis program which admits as the input thereof the design parameters previously input in conjunction with the program;

(f) checking said design parameter management part to see if there exist all design parameter values needed to execute the retrieved analysis program and, if any design parameter has yet to take on a value, outputting information requesting temporary determination of a value for the undetermined design parameter onto an output unit of the design department responsible for determining the value of said undetermined design parameter so that the responsible design department supplies a design parameter value, the step (f) being followed by the next step when all design parameters needed to execute said retrieved analysis program have been given values;

(g) checking said design parameter management part to see if there exists, among the design parameters needed to execute said retrieved analysis program, any design parameter associated with a trade-off among a plurality of design evaluation items, executing said retrieved analysis program if no design parameter exists in association with said trade-off and establishing a plurality of candidate design parameter values if any design parameter exists in association with said trade-off, so that said retrieved analysis program is executed on each of said candidate design parameter values;

(h) repeating the steps (f) and (g) for the analysis programs corresponding to all evaluation items, the step (h) being followed by the subsequent steps which are carried out depending on the result of each analysis program having been executed on each of the candidate values of said design parameter associated with said trade-off among said plurality of design evaluation items;

(i) approximating the analyzed result from said analysis program by use of a polynomial of said design parameter;

(j) translating to a normalized function the analyzed result approximated by use of said polynomial, the value of said normalized function being 1 when said analyzed result is the best and 0 when said analyzed result is the worst;

(k) obtaining an evaluation expression by multiplying a variable coefficient the function for all analyzed results acquired in the step (j) and by having the multiplied results added up;

(l) determining as the optimum value of said design parameter the design parameter value maximizing said evaluation expression; and

(m) outputting said evaluation expression and said optimum value onto said output unit.

5. The method for computer-assisted cooperative design according to claim 4 wherein, at said step (f) temporarily setting design parameter values, if said responsible design department does not supply the values of said undetermined design parameters, appropriate values are obtained from previously field-proven data for said design parameters.

6. The method for computer-assisted cooperative design according to claim 4 wherein, at step (h), at least one of said all evaluation items is an estimate value of the manufacturing cost.

7. A cooperative design support apparatus for use by a plurality of design means in cooperatively determining design specifications of a product having a plurality of design items, said cooperative design support apparatus comprising:

(a) a design parameter management means for storing either the names or the values of the design parameters for determining the design specifications of said product in conjunction with the name of the design means having the right to determine the values of said design parameters as well as the information about whether any of said design parameters are associated with a trade-off among a plurality of design evaluation items;

(b) an analysis program storage means for storing an analysis program for each of said design evaluation items in conjunction with the design parameters needed to perform said analysis program;

(c) a data input means for inputting the values of the design parameters which a given design means has a right to determine, together with any design evaluation items needed in conjunction with said design parameters;

(d) an analysis execution means whereby, if any design evaluation item was input through said data input means, the analysis program corresponding to the input design evaluation item is retrieved from said analysis program storage means and, if no design evaluation item was input, the analysis program which admits as the input thereof the design parameters previously input in conjunction with the program is retrieved from said analysis program storage means, whereby a check is made to see if there exists all design parameter values needed to execute the retrieved analysis program and, if any design parameter has yet to take on a value, a command is sent to a design parameter temporary determination request means for outputting information requesting temporary determination of a value for the undetermined design parameter onto an output unit of the design means responsible for determining the value of said undetermined design parameter so that the responsible design means supplies a design parameter value, whereby, if all design parameters needed to execute said retrieved analysis program have been given values, a check is made to see if there exists, among the design parameters needed to execute said retrieved analysis program, any design parameter associated with a trade-off among a plurality of design evaluation items, and whereby said retrieved analysis program is executed if no design parameter exists in association with said trade-off, and a plurality of candidate design parameter values are established if any design parameter exists in association with said trade-off, so that said retrieved analysis program is executed on each of said candidate design parameter values;

(e) an analyzed result storage means for storing the analyzed result from said analysis program;

(f) said design parameter temporary determination request means outputting the information requesting temporary determination of a value for any undetermined design parameter;

(g) a trade-off evaluation means for approximating the analyzed result from said analysis program using a polynomial of said design parameter associated with said trade-off among said plurality of design evaluation items, whereby the analyzed result approximated by use of said polynomial is translated into a normalized function, the value of said normalized function being 1 when said analyzed result is the best and 0 when said analyzed result is the worst, whereby an evaluation expression is obtained by multiplying the function for all analyzed results obtained by a variable coefficient and by summing the multiplied results, and whereby the design parameter value maximizing said evaluation expression is determined as the optimum value of said design parameter; and

(h) a result display means for outputting said evaluation expression and said optimum value onto said output unit.

8. The apparatus for cooperative design according to claim 7 further comprising workstations, each associated to one of said design items, and buses for connecting said workstations to each other through a communication control means, wherein said workstations may be installed at sites remote from each other.

9. The apparatus for cooperative design according to claim 8 further comprising workstations, each assigned to one of said design items, buses for connecting said workstations to each other through a communication control means and at least one central workstation connected to said buses, wherein each of said workstations assigned to said design items comprises at least data input means, design parameter management means and analysis means, whereas said central workstation includes at least means for performing total evaluation.