Talk:Umbrella
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(New page: ==Client comments on the Mechanical Analysis== It is a well-written mechanical analysis, which focuses on the U-shape linkage, a critical component in umbrella design. The analysis inclu...) |
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| + | =Client Comments on Report= | ||
| + | We received your [http://ddl.me.cmu.edu/ddwiki/index.php?title=Umbrella&oldid=16529 report]. Your most important findings seem to be that 1) the umbrella is already well optimized for DFMA, including the use of symmetry to reduce unique part count, 2) usability factors hold the most potential for improvement, and 3) that the top failure modes include canopy tearing and arm failure (which matches our data). You found that a 10 pound compressive axial load will buckle the current arm. Is compressive axial loading to cause buckling the primary mode of failure for these arms, rather than, for example, bending? We are looking forward to seeing your research findings and ideas in the next report. | ||
| + | Detailed comments follow: | ||
| + | # You mention the issue of nonuniform coverage; however, users often tip the umbrella rather than hold it perfectly vertical. How would this affect coverage and the drip pattern. | ||
| + | # Please include an assembly drawing with parts labeled to contextualize your parts list. Also, you did not include any text to describe the parts list. Were there any findings? | ||
| + | # Your list of stakeholder needs looks quite good, but you didn't include any text to introduce it. Are there any major trends or findings? | ||
| + | # You mention that there is much variability in attaching the handle to the shaft. Does this create problems in causing visual variation in a bin full of "identical" umbrellas that would communicate low quality to consumers and hurt sales? | ||
| + | # You mention that the fasteners do not need to be manufactured - do you mean that they are purchased from suppliers where they are manufactured at large economies of scale? | ||
| + | # Nice job in breaking down the product into categories for your LCA; however, wholesale trade would not capture assembly costs - only trade. You may reconsider your breakdown. | ||
| + | # What scale was used for your FMEA assessments? | ||
| + | # Your mechanical analysis is quite good, but is buckling under axial loading the most likely mechanism of failure? What role would shear flow play, given that this is an open channel design? You mention the possibility of a closed-channel design - would such a design still function in folding up, and would it strengthen the arms significantly? | ||
| + | # Your documentation of alternative umbrella designs is excellent, but we had difficulty understanding the description of the auto-open-close design from your text. Maybe a picture or diagram with labeled components would help to clarify. | ||
| + | # Please comment on your design process. | ||
==Client comments on the Mechanical Analysis== | ==Client comments on the Mechanical Analysis== | ||
It is a well-written mechanical analysis, which focuses on the U-shape linkage, a critical component in umbrella design. The analysis includes both analytical calculation and finite element simulation for the buckling with well described assumptions. | It is a well-written mechanical analysis, which focuses on the U-shape linkage, a critical component in umbrella design. The analysis includes both analytical calculation and finite element simulation for the buckling with well described assumptions. | ||
Revision as of 13:11, 30 September 2008
Client Comments on Report
We received your report. Your most important findings seem to be that 1) the umbrella is already well optimized for DFMA, including the use of symmetry to reduce unique part count, 2) usability factors hold the most potential for improvement, and 3) that the top failure modes include canopy tearing and arm failure (which matches our data). You found that a 10 pound compressive axial load will buckle the current arm. Is compressive axial loading to cause buckling the primary mode of failure for these arms, rather than, for example, bending? We are looking forward to seeing your research findings and ideas in the next report.
Detailed comments follow:
- You mention the issue of nonuniform coverage; however, users often tip the umbrella rather than hold it perfectly vertical. How would this affect coverage and the drip pattern.
- Please include an assembly drawing with parts labeled to contextualize your parts list. Also, you did not include any text to describe the parts list. Were there any findings?
- Your list of stakeholder needs looks quite good, but you didn't include any text to introduce it. Are there any major trends or findings?
- You mention that there is much variability in attaching the handle to the shaft. Does this create problems in causing visual variation in a bin full of "identical" umbrellas that would communicate low quality to consumers and hurt sales?
- You mention that the fasteners do not need to be manufactured - do you mean that they are purchased from suppliers where they are manufactured at large economies of scale?
- Nice job in breaking down the product into categories for your LCA; however, wholesale trade would not capture assembly costs - only trade. You may reconsider your breakdown.
- What scale was used for your FMEA assessments?
- Your mechanical analysis is quite good, but is buckling under axial loading the most likely mechanism of failure? What role would shear flow play, given that this is an open channel design? You mention the possibility of a closed-channel design - would such a design still function in folding up, and would it strengthen the arms significantly?
- Your documentation of alternative umbrella designs is excellent, but we had difficulty understanding the description of the auto-open-close design from your text. Maybe a picture or diagram with labeled components would help to clarify.
- Please comment on your design process.
Client comments on the Mechanical Analysis
It is a well-written mechanical analysis, which focuses on the U-shape linkage, a critical component in umbrella design. The analysis includes both analytical calculation and finite element simulation for the buckling with well described assumptions.
