Method for estimating changes in product life resulting from HALT using exponential acceleration model
View Patent ↗A method provides early estimation of product life using accelerated stress testing data. In an embodiment, data measured from a product operating in a first, high-stress environment is used to predict how long the product will operate in a second, normal operating environment before failure, using an exponential acceleration model. An additional feature of the present invention provides a quantified indication of how much the product has improved from a redesign.
1. A machine-readable medium storing computer-executable instructions to perform a method of estimating a life of a product, the method comprising:
determining accelerated stress testing data for the product using the relationship t F =AF×exp(t A ), the accelerated stress testing data representing the response of the product operating in a first environment; and
calculating the mean-time-between-failures (MTBF) for the product operating in a second environment based on the accelerated stress testing data,
wherein t F is a time to failure on a field use time scale, AF is an acceleration factor, and t A is a time to failure on an accelerated time scale.
2. The machine-readable medium of claim 1 , wherein said first environment is more likely than the second environment to cause the product to fail.
3. The machine-readable medium of claim 1 , wherein the accelerated stress testing data represents the length of time the product operates in the first environment before the product fails.
4. The machine-readable medium of claim 1 , wherein the accelerated stress testing data is derived from a plurality of different stress tests.
5. The machine-readable medium of claim 4 , wherein the plurality of different stress tests includes a temperature test and a vibrational test.
6. The machine-readable medium of claim 1 , the method further comprising calculating upper and lower confidence limits for the MTBF calculation.
7. The machine-readable medium of claim 1 , wherein said accelerated stress testing data is determined at least in part from bill of materials (BOM) information on the product.
8. The machine-readable medium of claim 1 , wherein said step of calculating is performed during the design of the product.
9. The machine-readable medium of claim 1 , wherein said step of calculating is performed prior to manufacturing the product for commercial use.
10. The machine-readable medium of claim 1 , wherein the accelerated stress testing data includes accelerated stress testing data for a previous design of the product.
11. The machine-readable medium of claim 10 , wherein the accelerated stress testing data for the previous design of the product is derived from stress testing in an environment less likely to cause failure than said first environment.
12. The machine-readable medium of claim 10 , the method further comprising calculating a change in MTBF from the previous design of the product.
13. The machine-readable medium of claim 10 , the method further comprising calculating a factor increase or decrease in the life of the product as compared to the life of the previous design of the product.
14. The machine-readable medium of claim 10 , wherein the accelerated stress testing data is derived from a plurality of different stress tests.
15. The machine-readable medium of claim 14 , wherein the different stress tests include a temperature test and a vibrational test.
16. The machine-readable medium of claim 10 , wherein said step of calculating is performed during the design of the product.
17. The machine-readable medium of claim 10 , wherein said step of calculating is performed prior to manufacturing the product for commercial use.
18. A machine-readable medium storing computer-executable instructions to perform a method of estimating a life of a product, the method comprising:
determining accelerated stress testing data for the product using the relationship t F =AF×exp(t A ), the accelerated stress testing data representing the response of the product operating in a first environment; and
calculating the mean-time-between-failures (MTBF) for the product operating in a second environment based on the accelerated stress testing data,
wherein said first environment is more likely than the second environment to cause the product to fail;
wherein the accelerated stress testing data is derived from a plurality of different stress tests; and
wherein t F is a time to failure on a field use time scale, AF is an acceleration factor, and t A is a time to failure on an accelerated time scale.
19. A machine-readable medium storing computer-executable instructions to perform a method of estimating a life of a product, the method comprising:
determining accelerated stress testing data for the product using the relationship t F =AF×exp(t A ), the accelerated stress testing data representing the response of the product operating in a first environment; and
calculating the mean-time-between-failures (MTBF) for the product operating in a second environment based on the accelerated stress testing data,
wherein said first environment is more likely than the second environment to cause the product to fail;
wherein said accelerated stress testing data is determined at least in part from bill of materials (BOM) information on the product; and
wherein t F is a time to failure on a field use time scale, AF is an acceleration factor, and t A is a time to failure on an accelerated time scale.