Template:Paper Clip Example - Revision history

Kate Racaza: Redirected page to Paper Clip Example

2012-08-15T00:19:26Z

← Older revision		Revision as of 00:19, 15 August 2012
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	~~===Paper Clip Example===~~		#REDIRECT[[Paper_Clip_Example]]

	To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and independently performed by the reader. The objective was to determine the mean number of cycles-to-failure of a given paper clip. The use cycles were assumed to be at a 45º bend. The acceleration stress was determined to be the angle to which we bend the clips, thus two accelerated bend stresses of 90º and 180º were used. The paper clips were tested using the following procedure for the 90º bend. A similar procedure was also used for the 180º and 45º test.

	*'''Open the Paper Clip.'''

	[[~~Image:openclip.png\|center\|150px\|]]~~

	~~:1) With one hand, hold the clip by the longer, outer loop.~~

	~~:2) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.~~

	~~:3) Pull the smaller, inner loop out and down 90 degrees so that a right angle is formed as shown.~~

	*'''Close the Paper Clip.'''

	~~[[Image:closeclip.png\|center\|150px\|]]~~

	~~:1) With one hand, continue to hold the clip by the longer, outer loop.~~

	~~:2) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.~~

	~~:3) Push the smaller inner loop up and in 90 degrees so that the smaller loop is returned to the original upright position in line with the larger, outer loop as shown.~~

	~~:4) This completes one cycle.~~

	~~:5) Repeat until the paper clip breaks. Count and record the cycles-to-failure for each clip.~~

	At this point, the reader must note that the paper clips used in this example were Jumbo paper clips capable of repeated bending. Different paper clips will yield different results. Additionally, and so that no other stresses are imposed, caution must be taken to assure that the rate at which the paper clips are cycled remains the same across the experiment.

	For the experiment, a sample of six paper clips was tested to failure at both 90º and 180º bends. A base test sample of six paper clips was tested at a 45º bend (the assumed use stress level) to confirm the analysis. The cycles-to-failure are given next.

	~~<div style="text-align: center;"> '''Cycles-to-Failure at <math>90^\circ </math> [[File:90degree.gif]] </div>~~
	~~<br>~~
	~~<div style="text-align: center;"> 16, 17, 18, 21, 22, 23 cycles.</div>~~
	~~<br>~~
	~~<div style="text-align: center;"> '''Cycles-to-Failure at <math>180^\circ </math> [[File:180degree.gif]]</div>~~
	~~<br>~~
	~~<div style="text-align: center;"> 4, 4, 5, 6, 6, 8 cycles.</div>~~
	~~<br>~~
	~~<div style="text-align: center;"> '''Cycles-to-Failure at <math>45^\circ </math> [[File:45degree.gif]]</div>~~
	~~<br>~~
	~~<div style="text-align: center;"> 58, 63, 65, 72, 78, 86 cycles.</div>~~

	The accelerated test data set was then analyzed in ALTA, assuming a lognormal life distribution (fatigue) and an inverse power law relationship (non-thermal) for the life-stress model. The analysis and some of the results are shown in the next figures.

	~~[[Image:degreesbend.png\|thumb\|center\|650px\|The accelerated test data analyzed in ALTA.]]~~


	~~[[Image:probweib.png\|thumb\|center\|550px\|Lognormal probability plot of both stress levels from ALTA.]]~~


	~~[[Image:accvsstress.png\|thumb\|center\|550px\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]~~

	~~The MTTF at 45 degrees is found to be 71.375467 cycles as shown next.~~

	~~[[Image:Ch12-Ex1-4.png\|thumb\|center\|400px\|The Mean Life at 45 degrees bend.]]~~

	~~The next two figures show the analysis of the base data in Weibull++ and the base MTTF estimate. In this case, our accelerated test correctly predicted the MTTF as verified by our base test.~~

	~~[[Image:ALTA14.5b.gif\|thumb\|center\|500px\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]~~

	~~[[Image:ALTA14.5.gif\|thumb\|center\|400px\|Calculated Mean Life from base test.~~]]

Richard House: /* Paper Clip Example */

2012-08-09T07:13:44Z

Paper Clip Example

← Older revision		Revision as of 07:13, 9 August 2012
Line 3:		Line 3:
	To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and independently performed by the reader. The objective was to determine the mean number of cycles-to-failure of a given paper clip. The use cycles were assumed to be at a 45º bend. The acceleration stress was determined to be the angle to which we bend the clips, thus two accelerated bend stresses of 90º and 180º were used. The paper clips were tested using the following procedure for the 90º bend. A similar procedure was also used for the 180º and 45º test.		To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and independently performed by the reader. The objective was to determine the mean number of cycles-to-failure of a given paper clip. The use cycles were assumed to be at a 45º bend. The acceleration stress was determined to be the angle to which we bend the clips, thus two accelerated bend stresses of 90º and 180º were used. The paper clips were tested using the following procedure for the 90º bend. A similar procedure was also used for the 180º and 45º test.

			*'''Open the Paper Clip.'''

			[[Image:openclip.png\|center\|150px\|]]

			:1) With one hand, hold the clip by the longer, outer loop.

	~~1) '''Open the Paper Clip.'''~~		:2) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.
	~~<br>~~
	~~[[Image~~:~~openclip.png\|center\|150px\|]]~~
	~~<br>~~
	2) With ~~one~~ hand, ~~hold the clip by~~ the ~~longer~~, ~~outer~~ loop.

	3) ~~With the thumb and forefinger of the other hand, grasp~~ the smaller, inner loop.		:3) Pull the smaller, inner loop out and down 90 degrees so that a right angle is formed as shown.

	~~4) Pull~~ the ~~smaller, inner loop out and down 90 degrees so that a right angle is formed as shown~~.		*'''Close the Paper Clip.'''

	~~5) '''Close the Paper Clip.'''~~
	~~<br>~~
	[[Image:closeclip.png\|center\|150px\|]]		[[Image:closeclip.png\|center\|150px\|]]
	~~<br>~~
	6) With one hand, continue to hold the clip by the longer, outer ~~loop.~~		:1) With one hand, continue to hold the clip by the longer, outer loop.

	~~7) With the thumb and forefinger of the other hand, grasp the smaller, inner~~ loop.

	8) ~~Push~~ the ~~smaller inner loop up~~ and ~~in 90 degrees so that~~ the smaller ~~loop is returned to the original upright position in line with the larger~~, ~~outer~~ loop ~~as shown~~.		:2) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.

	9) ~~This completes one cycle~~.		:3) Push the smaller inner loop up and in 90 degrees so that the smaller loop is returned to the original upright position in line with the larger, outer loop as shown.

	10) ~~Repeat until the paper clip breaks. Count and record the cycles-to-failure for each clip~~.		:4) This completes one cycle.

			:5) Repeat until the paper clip breaks. Count and record the cycles-to-failure for each clip.

	At this point, the reader must note that the paper clips used in this example were Jumbo paper clips capable of repeated bending. Different paper clips will yield different results. Additionally, and so that no other stresses are imposed, caution must be taken to assure that the rate at which the paper clips are cycled remains the same across the experiment.		At this point, the reader must note that the paper clips used in this example were Jumbo paper clips capable of repeated bending. Different paper clips will yield different results. Additionally, and so that no other stresses are imposed, caution must be taken to assure that the rate at which the paper clips are cycled remains the same across the experiment.


	For the experiment, a sample of six paper clips was tested to failure at both 90º and 180º bends. A base test sample of six paper clips was tested at a 45º bend (the assumed use stress level) to confirm the analysis. The cycles-to-failure are given next.		For the experiment, a sample of six paper clips was tested to failure at both 90º and 180º bends. A base test sample of six paper clips was tested at a 45º bend (the assumed use stress level) to confirm the analysis. The cycles-to-failure are given next.


	<div style="text-align: center;"> '''Cycles-to-Failure at <math>90^\circ </math> [[File:90degree.gif]] </div>		<div style="text-align: center;"> '''Cycles-to-Failure at <math>90^\circ </math> [[File:90degree.gif]] </div>
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	<div style="text-align: center;"> 58, 63, 65, 72, 78, 86 cycles.</div>		<div style="text-align: center;"> 58, 63, 65, 72, 78, 86 cycles.</div>

	~~<br>~~
	The accelerated test data set was then analyzed in ALTA, assuming a lognormal life distribution (fatigue) and an inverse power law relationship (non-thermal) for the life-stress model. The analysis and some of the results are shown in the next figures.		The accelerated test data set was then analyzed in ALTA, assuming a lognormal life distribution (fatigue) and an inverse power law relationship (non-thermal) for the life-stress model. The analysis and some of the results are shown in the next figures.

			[[Image:degreesbend.png\|thumb\|center\|650px\|The accelerated test data analyzed in ALTA.]]


			[[Image:probweib.png\|thumb\|center\|550px\|Lognormal probability plot of both stress levels from ALTA.]]


	~~[[Image:degreesbend.png\|thumb\|center\|650px\|The accelerated test data analyzed in ALTA.]]~~		[[Image:accvsstress.png\|thumb\|center\|550px\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]
	~~<br>~~
	~~<br>~~
	~~[[Image:probweib.png\|thumb\|center\|500px\|Lognormal probability plot of both stress levels from ALTA.]]~~
	~~<br>~~
	~~<br>~~
	[[Image:accvsstress.png\|thumb\|center\|~~500px~~\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]

	~~<br>~~
	The MTTF at 45 degrees is found to be 71.375467 cycles as shown next.		The MTTF at 45 degrees is found to be 71.375467 cycles as shown next.

	~~<br>~~
	[[Image:Ch12-Ex1-4.png\|thumb\|center\|400px\|The Mean Life at 45 degrees bend.]]		[[Image:Ch12-Ex1-4.png\|thumb\|center\|400px\|The Mean Life at 45 degrees bend.]]


	The next two figures show the analysis of the base data in Weibull++ and the base MTTF estimate. In this case, our accelerated test correctly predicted the MTTF as verified by our base test.		The next two figures show the analysis of the base data in Weibull++ and the base MTTF estimate. In this case, our accelerated test correctly predicted the MTTF as verified by our base test.

	~~<br>~~
	[[Image:ALTA14.5b.gif\|thumb\|center\|500px\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]		[[Image:ALTA14.5b.gif\|thumb\|center\|500px\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]

	~~<br>~~
	[[Image:ALTA14.5.gif\|thumb\|center\|400px\|Calculated Mean Life from base test.]]		[[Image:ALTA14.5.gif\|thumb\|center\|400px\|Calculated Mean Life from base test.]]

	~~<br>~~

Chris Kahn: /* Paper Clip Example */

2012-06-25T13:16:10Z

Paper Clip Example

← Older revision		Revision as of 13:16, 25 June 2012
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	[[Image:degreesbend.png\|thumb\|center\|~~200px~~\|The accelerated test data analyzed in ALTA.]]		[[Image:degreesbend.png\|thumb\|center\|650px\|The accelerated test data analyzed in ALTA.]]
	<br>		<br>
	<br>		<br>
	[[Image:probweib.png\|thumb\|center\|~~200px~~\|Lognormal ~~probabiliyt~~ plot of both stress levels from ALTA.]]		[[Image:probweib.png\|thumb\|center\|500px\|Lognormal probability plot of both stress levels from ALTA.]]
	<br>		<br>
	<br>		<br>
	[[Image:accvsstress.png\|thumb\|center\|~~200px~~\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]		[[Image:accvsstress.png\|thumb\|center\|500px\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]

	<br>		<br>
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	<br>		<br>
	[[Image:Ch12-Ex1-4.png\|thumb\|center\|~~200px~~\|The Mean Life at 45 degrees bend.]]		[[Image:Ch12-Ex1-4.png\|thumb\|center\|400px\|The Mean Life at 45 degrees bend.]]


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	<br>		<br>
	[[Image:ALTA14.5b.gif\|thumb\|center\|~~150px~~\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]		[[Image:ALTA14.5b.gif\|thumb\|center\|500px\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]

	<br>		<br>
	[[Image:ALTA14.5.gif\|thumb\|center\|~~200px~~\|Calculated Mean Life from base test.]]		[[Image:ALTA14.5.gif\|thumb\|center\|400px\|Calculated Mean Life from base test.]]

	<br>		<br>

Chuck Smith: /* Paper Clip Example */

2012-04-25T23:28:21Z

Paper Clip Example

← Older revision		Revision as of 23:28, 25 April 2012
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	1) '''Open the Paper Clip.'''		1) '''Open the Paper Clip.'''
	<br>		<br>
	[[Image:openclip.png\|center\|~~300px~~\|]]		[[Image:openclip.png\|center\|150px\|]]
	<br>		<br>
	2) With one hand, hold the clip by the longer, outer loop.		2) With one hand, hold the clip by the longer, outer loop.
Line 17:		Line 17:
	5) '''Close the Paper Clip.'''		5) '''Close the Paper Clip.'''
	<br>		<br>
	[[Image:closeclip.png\|center\|~~300px~~\|]]		[[Image:closeclip.png\|center\|150px\|]]
	<br>		<br>
	6) With one hand, continue to hold the clip by the longer, outer loop.		6) With one hand, continue to hold the clip by the longer, outer loop.
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	[[Image:degreesbend.png\|thumb\|center\|~~400px~~\|The accelerated test data analyzed in ALTA.]]		[[Image:degreesbend.png\|thumb\|center\|200px\|The accelerated test data analyzed in ALTA.]]
	<br>		<br>
	<br>		<br>
	[[Image:probweib.png\|thumb\|center\|~~400px~~\|Lognormal probabiliyt plot of both stress levels from ALTA.]]		[[Image:probweib.png\|thumb\|center\|200px\|Lognormal probabiliyt plot of both stress levels from ALTA.]]
	<br>		<br>
	<br>		<br>
	[[Image:accvsstress.png\|thumb\|center\|~~400px~~\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]		[[Image:accvsstress.png\|thumb\|center\|200px\|The resulting Acceleration Factor vs. Stress plot from ALTA.]]

	<br>		<br>
Line 64:		Line 64:

	<br>		<br>
	[[Image:Ch12-Ex1-4.png\|thumb\|center\|~~400px~~\|The Mean Life at 45 degrees bend.]]		[[Image:Ch12-Ex1-4.png\|thumb\|center\|200px\|The Mean Life at 45 degrees bend.]]


Line 70:		Line 70:

	<br>		<br>
	[[Image:ALTA14.5b.gif\|thumb\|center\|~~300px~~\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]		[[Image:ALTA14.5b.gif\|thumb\|center\|150px\|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]

	<br>		<br>
	[[Image:ALTA14.5.gif\|thumb\|center\|~~400px~~\|Calculated Mean Life from base test.]]		[[Image:ALTA14.5.gif\|thumb\|center\|200px\|Calculated Mean Life from base test.]]

	<br>		<br>

Nikki Helms: /* Paper Clip Example */

2012-04-02T17:47:04Z

Paper Clip Example

← Older revision		Revision as of 17:47, 2 April 2012
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	1) '''Open the Paper Clip.'''		1) '''Open the Paper Clip.'''
	<br>		<br>
	[[Image:openclip.~~gif\|thumb~~\|center\|300px\|]]		[[Image:openclip.png\|center\|300px\|]]
	<br>		<br>
	2) With one hand, hold the clip by the longer, outer loop.		2) With one hand, hold the clip by the longer, outer loop.
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	5) '''Close the Paper Clip.'''		5) '''Close the Paper Clip.'''
	<br>		<br>
	[[Image:closeclip.~~gif\|thumb~~\|center\|300px\|]]		[[Image:closeclip.png\|center\|300px\|]]
	<br>		<br>
	6) With one hand, continue to hold the clip by the longer, outer loop.		6) With one hand, continue to hold the clip by the longer, outer loop.

Nikki Helms at 21:51, 21 March 2012

2012-03-21T21:51:48Z

← Older revision		Revision as of 21:51, 21 March 2012
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	~~[[Paper Clip Example]]~~
	===Paper Clip Example===		===Paper Clip Example===

Nikki Helms at 21:47, 21 March 2012

2012-03-21T21:47:38Z

← Older revision		Revision as of 21:47, 21 March 2012
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			[[Paper Clip Example]]
	===Paper Clip Example===		===Paper Clip Example===

Athanasios Gerokostopoulos: Created page with '===Paper Clip Example=== To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and indepen…'

2012-03-21T17:30:30Z

Created page with '===Paper Clip Example=== To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and indepen…'

New page

===Paper Clip Example===

To illustrate the principles behind accelerated testing, consider the following simple example which involves a paper clip and can be easily and independently performed by the reader. The objective was to determine the mean number of cycles-to-failure of a given paper clip. The use cycles were assumed to be at a 45º bend. The acceleration stress was determined to be the angle to which we bend the clips, thus two accelerated bend stresses of 90º and 180º were used. The paper clips were tested using the following procedure for the 90º bend. A similar procedure was also used for the 180º and 45º test.

1) '''Open the Paper Clip.'''
<br>
[[Image:openclip.gif|thumb|center|300px|]]
<br>
2) With one hand, hold the clip by the longer, outer loop.

3) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.

4) Pull the smaller, inner loop out and down 90 degrees so that a right angle is formed as shown.

5) '''Close the Paper Clip.'''
<br>
[[Image:closeclip.gif|thumb|center|300px|]]
<br>
6) With one hand, continue to hold the clip by the longer, outer loop.

7) With the thumb and forefinger of the other hand, grasp the smaller, inner loop.

8) Push the smaller inner loop up and in 90 degrees so that the smaller loop is returned to the original upright position in line with the larger, outer loop as shown.

9) This completes one cycle.

10) Repeat until the paper clip breaks. Count and record the cycles-to-failure for each clip.

At this point, the reader must note that the paper clips used in this example were Jumbo paper clips capable of repeated bending. Different paper clips will yield different results. Additionally, and so that no other stresses are imposed, caution must be taken to assure that the rate at which the paper clips are cycled remains the same across the experiment.

For the experiment, a sample of six paper clips was tested to failure at both 90º and 180º bends. A base test sample of six paper clips was tested at a 45º bend (the assumed use stress level) to confirm the analysis. The cycles-to-failure are given next.

<div style="text-align: center;"> '''Cycles-to-Failure at <math>90^\circ </math> [[File:90degree.gif]] </div>
<br>
<div style="text-align: center;"> 16, 17, 18, 21, 22, 23 cycles.</div>
<br>
<div style="text-align: center;"> '''Cycles-to-Failure at <math>180^\circ </math> [[File:180degree.gif]]</div>
<br>
<div style="text-align: center;"> 4, 4, 5, 6, 6, 8 cycles.</div>
<br>
<div style="text-align: center;"> '''Cycles-to-Failure at <math>45^\circ </math> [[File:45degree.gif]]</div>
<br>
<div style="text-align: center;"> 58, 63, 65, 72, 78, 86 cycles.</div>

<br>
The accelerated test data set was then analyzed in ALTA, assuming a lognormal life distribution (fatigue) and an inverse power law relationship (non-thermal) for the life-stress model. The analysis and some of the results are shown in the next figures.

[[Image:degreesbend.png|thumb|center|400px|The accelerated test data analyzed in ALTA.]]
<br>
<br>
[[Image:probweib.png|thumb|center|400px|Lognormal probabiliyt plot of both stress levels from ALTA.]]
<br>
<br>
[[Image:accvsstress.png|thumb|center|400px|The resulting Acceleration Factor vs. Stress plot from ALTA.]]

<br>
The MTTF at 45 degrees is found to be 71.375467 cycles as shown next.

<br>
[[Image:Ch12-Ex1-4.png|thumb|center|400px|The Mean Life at 45 degrees bend.]]

The next two figures show the analysis of the base data in Weibull++ and the base MTTF estimate. In this case, our accelerated test correctly predicted the MTTF as verified by our base test.

<br>
[[Image:ALTA14.5b.gif|thumb|center|300px|The base <math>45^\circ </math> data analyzed in ReliaSoft's Weibull++, utilizing a lognormal distribution shown on lognormal probability paper.]]

<br>
[[Image:ALTA14.5.gif|thumb|center|400px|Calculated Mean Life from base test.]]

<br>