Design maturity algorithm

• US 6,247,366 B1
• Filed: 05/21/1999
• Issued: 06/19/2001
• Est. Priority Date: 09/15/1997
• Status: Expired due to Term

• Current Assignee: Intertek Testing Services NA Incorporated (Intertek Group PLC)
• Original Assignee: Entela, Inc. (ETL SEMKO)
• Inventors: Porter, Alexander J.
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): MILLER, ROSE MARY
• Application Number:
  US09/316,574
• Time in Patent Office: 760 Days
• Field of Search: 736/62, 736/63, 736/64, 736/65, 736/66, 736/67, 736/68, 738/656, 738/659, 738/66, 734/321, 736/72, 735/71, 735/73, 735/74, 737/88, 737/94
• US Class Current: 73/571
• CPC Class Codes: G01M 7/02 Vibration-testing by means of a shake table
• CPC Class Codes: G01M 7/022 Vibration control arrangements, e.g. for generating random vibrations
• CPC Class Codes: G01M 7/04 Monodirectional test stands
• CPC Class Codes: G01M 7/06 Multidirectional test stands
• CPC Class Codes: G01M 99/007 by applying a load, e.g. for resistance or wear testing G01M99/001 takes precedence; testing the elasticity of structures G01M5/00
• CPC Class Codes: G01N 2203/0222 Temperature
• CPC Class Codes: G01N 2203/0256 Triaxial, i.e. the forces being applied along three normal axes of the specimen
• CPC Class Codes: G01N 2291/02827 Elastic parameters, strength or force
• CPC Class Codes: G01N 2291/2698 Other discrete objects, e.g. bricks
• CPC Class Codes: G01N 29/045 by imparting shocks to the workpiece and detecting the vibrations or the acoustic waves caused by the shocks measuring resonant frequency G01H13/00; measuring strength properties by application of mechanical stress G01N3/00
• CPC Class Codes: G01N 29/12 by measuring frequency or resonance of acoustic waves measuring frequency or resonant frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04, G01H13/00; acoustic resonators G10K11/04; vibration or shock testing of structures G01M7/00
• CPC Class Codes: G01N 29/46 by spectral analysis, e.g. Fourier analysis or wavelet analysis spectral signal processing per se G06F17/14
• CPC Class Codes: G01N 3/32 by applying repeated or pulsating forces
• CPC Class Codes: G11B 33/14 Reducing influence of physical parameters, e.g. temperature change, moisture, dust

Abstract

An apparatus for optimizing the design of a product or component by subjecting the product or component to multiple stimuli, such as temperature, vibration, pressure, ultraviolet radiation, chemical exposure, humidity, mechanical cycling, and mechanical loading, is described. Also described is a method for determining design maturity, technological limits, technological design maturity, predicted technological design maturity, and system target limits of products, components, and systems, respectively.

Claims

1. An apparatus for applying a force to a product, comprising:

at least one member for imparting a force, said at least one force imparting member being capable of creating six axis uniform random stresses in the product;

at least one member for transferring the force from said at least one force imparting member to the product, said at least one force transfer member engaging said at least one force imparting member;

at least one mounting member for mounting the product thereto, said at least one mounting member engaging said at least one force transfer member; and

at least one member for allowing said at least one force transfer member to move longitudinally and in all three axes.

2. An apparatus in accordance with claim 1, further comprising:

a base;

at least one support member, said at least one support member having first and second ends, said first end of said at least one support member being fastened to said base, said at least one force imparting member being fastened to said at least one support member;

at least one actuator member for actuating said at least one force imparting member; and

a planar member, said second ends of said at least one support member being fastened to said planar member, said planar member having an area defining an aperture, said at least one force transfer member extending through the aperture of said planar member.

3. An apparatus in accordance with claim 1, further comprising a first enclosure enclosing said at least one force imparting member.

4. An apparatus in accordance with claim 3, wherein said first enclosure includes an area defining an aperture for receiving said at least one force transfer member.

5. An apparatus in accordance with claim 3, further comprising a second enclosure for enclosing said at least one mounting member.

6. An apparatus in accordance with claim 5, wherein said second enclosure comprises an environmental chamber.

7. An apparatus in accordance with claim 5, wherein said second enclosure includes an area defining an aperture for receiving said at least one force transfer member.

8. An apparatus in accordance with claim 5, further comprising a third enclosure disposed between said first and second enclosures.

9. An apparatus in accordance with claim 1, further comprising:

a device for subjecting the product to vibration;

optionally, a device for subjecting the product to a temperature;

optionally, a device for subjecting the product to pressure;

optionally, a device for subjecting the product to ultraviolet radiation;

optionally, a device for subjecting the product to chemical exposure;

optionally, a device for subjecting the product to humidity;

optionally, a device for subjecting the product to mechanical cycling; and

optionally, a device for subjecting the product to mechanical loading.

10. An apparatus in accordance with claim 9, further comprising:

a device for controlling the amount of vibration that the product is subjected to by the apparatus;

optionally, a device for controlling the level of temperature that the product is subjected to by the apparatus;

optionally, a device for controlling the level of pressure that the product is subjected to by the apparatus;

optionally, a device for controlling the level of ultraviolet radiation that the product is subjected to by the apparatus;

optionally, a device for controlling the level of chemical exposure that the product is subjected to by the apparatus;

optionally, a device for controlling the level of humidity that the product is subjected to by the apparatus;

optionally, a device for controlling the amount of mechanical cycling that the product is subjected to by the apparatus; and

optionally, a device for controlling the amount of mechanical loading that the product is subjected to by the apparatus.

11. An apparatus in accordance with claim 1, wherein said at least one force imparting member comprises a plurality of actuators, said plurality of actuators operating at different frequencies with respect to one another, wherein the difference in frequencies of said plurality of actuators creates a six axis uniform random stress in the product, said plurality of actuators being capable of producing a frequency in the range of about 2 Hz to about infinity.

12. An apparatus in accordance with claim 1, wherein there are three force transfer members.

13. An apparatus in accordance with claim 1, wherein said at least one force transfer member comprises an elongated member.

14. An apparatus in accordance with claim 1, wherein said at least one force transfer member has first and second spaced and opposed ends, said first and second ends having a ball-shaped member extending therefrom.

15. An apparatus in accordance with claim 1, wherein said at least one mounting member has first and second spaced and opposed ends, said first and second ends having an area defining a socket disposed therein.

16. An apparatus in accordance with claim 15, wherein said ball-shaped member engages said socket so at to permit said at least one force transfer member to rotate freely about said at least one mounting member.

17. An apparatus in accordance with claim 1, further comprising at least one hub member engaging said at least one force imparting member and said at least one force transfer member.

18. An apparatus in accordance with claim 17, wherein said at least one hub member includes a surface having an area defining a socket disposed therein.

19. An apparatus in accordance with claim 18, wherein said ball-shaped member engages said socket so at to permit said at least one force transfer member to rotate freely about said at least one hub member.

20. An apparatus in accordance with claim 1, wherein said at least one member for allowing said force transfer member to move longitudinally and in all three axes comprises a gimbal.

21. A method for determining the design maturity measure of a product that has encountered at least first and second unique failure modes during an elapsed time period of a stress test procedure or any portion thereof, comprising:

(a) determining the total number of unique failure modes (N) encountered during the stress test procedure or any portion thereof;

(b) determining the elapsed time period until the first unique failure mode was encountered (Y) during the stress test procedure or any portion thereof;

(c) determining the elapsed time period until the second unique failure mode was encountered (X) during the stress test procedure or any portion thereof; and

(d) calculating the design maturity measure in accordance with the formula;

[((X−

Y)/(N−

1))/Y];

wherein X is the elapsed time period until a final unique failure mode was encountered, or any other unique failure mode was encountered other than an initial unique failure mode, during the stress test procedure or any portion thereof;

wherein Y is the elapsed time period until the initial unique failure mode was encountered, or any other unique failure mode was encountered other than the final unique failure mode, during the stress test procedure or any portion thereof; and

N is the total number of unique failure modes encountered during the stress test procedure or any portion thereof.

22. The method in accordance with claim 21, further comprising calculating the design maturity measure percentage in accordance with the algorithm:

[(DMM)100];

wherein DMM is the design maturity measure.

23. The method in accordance with claim 21, further comprising recording the total number of unique failure modes encountered.

24. The method in accordance with claim 21, further comprising recording the elapsed time until the at least first failure mode was encountered.

25. The method in accordance with claim 21, further comprising recording the elapsed time until the at least second failure mode was encountered.

26. A method for determining the primary technological limit of a product that has encountered at least first and second unique failure modes during an elapsed time period of a stress test procedure, comprising:

determining the design maturity measure in accordance with the formula;

(((X−

Y)/(N−

1))/Y);

wherein X is the elapsed time period until a final unique failure mode was encountered, or any other unique failure mode was encountered other than an initial unique failure mode, during the stress test procedure;

wherein Y is the elapsed time period until the initial unique failure mode was encountered, or any other unique failure mode was encountered other than the final unique failure mode, during the stress test procedure; and

N is the total number of unique failure modes encountered during the stress test procedure; and

determining if the design maturity measure is less than or greater than 0.1;

wherein the primary technological limit of the product is defined as either the shortest elapsed time period in which a unique failure mode was encountered that had a design maturity measure of less than 0.1, or if there is not a unique failure mode that has a design maturity measure of less than 0.1, then the elapsed time period of the stress test procedure.

27. The method in accordance with claim 26, further comprising identifying the shortest elapsed time period in which a unique failure mode was encountered that had a design maturity measure of less than 0.1.

28. A method for determining the secondary technological limit of a product that has encountered at least first and second unique failure modes during an elapsed time period of a stress test procedure, comprising:

determining the design maturity measure in accordance with the formula;

(((X−

Y)/(N−

1))/Y);

wherein X is the elapsed time period until a final unique failure mode was encountered, or any other unique failure mode was encountered other than an initial unique failure mode, during the stress test procedure;

wherein Y is the elapsed time period until the initial unique failure mode was encountered, or any other unique failure mode was encountered other than the final unique failure mode, during the stress test procedure; and

N is the total number of unique failure modes encountered during the stress test procedure; and

determining if the design maturity measure change is less than or greater than 0.1 between any two sequential unique failure modes;

wherein the secondary technological limit of the product is defined as either the shortest cumulative time under the stress test procedure in which the difference in design maturity measure between any two sequential unique failure modes is less than 0.1, or if there is not a design maturity measure change of less than 0.1 between any two sequential unique failure modes, then the elapsed time period of the stress test procedure.

29. The method in accordance with claim 28, further comprising identifying the shortest elapsed time period in which a unique failure mode was encountered that had a design maturity measure change of less than 0.1.

30. A method for determining the primary technological design maturity measure of a system having at least two components, wherein the components have at least one primary technological limit, comprising:

determining the highest primary technological limit of any of the components of the system based on time;

determining the lowest primary technological limit of any of the components of the system based on time; and

determining the primary technological design maturity measure of the system in accordance with the formula;

[((PT_MAX)−

(PT_MIN))/(N−

1))/(PT_MIN)];

wherein PT_MAX is the highest primary technological limit of any of the components of the system based on time;

wherein PT_MIN is the lowest primary technological limit of any of the components of the system based on time; and

wherein N is the number of components of the system.

31. A method for determining the secondary technological design maturity measure of a system having at least two components, wherein the components have at least one secondary technological limit, comprising:

determining the highest secondary technological limit of any of the components of the system based on time;

determining the lowest secondary technological limit of any of the components of the system based on time; and

determining the secondary technological design maturity measure of the system in accordance with the formula;

[((ST_MAX)−

(ST_MIN))/(N−

1))/(ST_MIN)];

wherein ST_MAX is the highest secondary technological limit of any of the components of the system based on time;

wherein ST_MIN is the lowest secondary technological limit of any of the components of the system based on time; and

wherein N is the number of components of the system.

32. A method for determining the predicted primary technological design maturity measure of a system having at least two components, wherein the components have at least one primary technological limit, comprising:

determining the highest primary technological limit of any of the components of the system based on time;

determining the penultimate lowest primary technological limit of any of the components of the system based on time; and

determining the predicted primary technological design maturity measure of the system in accordance with formula;

[(PT_MAX)−

(PT_2MIN))/(N−

1))/(PT_2MIN)];

wherein PT_MAX is the highest primary technological limit of any of the components of the system based on time;

wherein PT_2MIN is the penultimate lowest primary technological limit of any of the components of the system based on time; and

wherein N is the number of components of the system.

33. A method for determining the predicted secondary technological design maturity measure of a system having at least two components, wherein the components have at least one secondary technological limit, comprising:

determining the highest secondary technological limit of any of the components of the system based on time;

determining the penultimate lowest secondary technological limit of any of the components of the system based on time; and

determining the predicted secondary technological design maturity measure of the system in accordance with formula;

[((ST_MAX)−

(ST_2MIN))/(N−

1)/(ST_2MIN)];

wherein ST_MAX is the highest secondary technological limit of any of the components of the system based on time;

wherein ST_2MIN is the penultimate lowest secondary technological limit of any of the components of the system based on time; and

wherein N is the number of components of the system.

34. A method for determining the primary system target limit, wherein the system has at least one primary technological limit, the at least one primary technological limit having an elapsed time associated therewith, comprising:

determining which, if any, of the primary technological limits are associated with a design maturity measure of less than 0.1 based on either a primary technological design maturity determination or a predicted primary technological design maturity measure determination;

wherein if there is at least one primary technological limit associated with a design maturity measure of less than 0.1, then the primary technological limit having the shortest elapsed time is the primary system target limit;

wherein if there is no primary technological limit associated with a design maturity measure of less than 0.1, then the primary technological limit having the longest elapsed time is the primary system target limit.

35. A method for determining the secondary system target limit, wherein the system has at least one secondary technological limit, the at least one secondary technological limit having an elapsed time associated therewith, comprising:

determining which, if any, of the secondary technological limits are associated with a design maturity measure of less than 0.1 based on either a secondary technological design maturity determination or a predicted secondary technological design maturity measure determination;

wherein if there is at least one secondary technological limit associated with a design maturity measure of less than 0.1, then the secondary technological limit having the shortest elapsed time is the secondary system target limit;

wherein if there is no secondary technological limit associated with a design maturity measure of less than 0.1, then the secondary technological limit having the longest elapsed time is the secondary system target limit.