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Revision as of 20:24, 20 March 2007

First Report

We received your report on the active climbing cam and were impressed with your work; however, we wish you had made your conclusions and recommendations more clear and up front. Detailed comments follow:

• In our company (and in most companies that we know of) the executive summary typically outlines your conclusions, not just a summary of what topics will be discussed in the report. This would be helpful for us in the next report, since our executives typically do not have time to read the full report.
  • Ans: For the first stage of our design, we were able to do product dissections and perform some analysis. Because of a failure of our product is fatal to its users, we recognized some important requirements. The product must be able to withstand a big dynamic load, it must be long lasting and the signs of damage should be clear. We have identified a few customer needs in order to direct us to the right path in redesigning our product. Some of these needs are less weight, easy placement and removal, easy to handle harness, affordable, low maintenance and accommodates different hand sizes. Of all these are important when we are thinking of opportunities in redesigning our product. We were able to disassemble our product although it was a bit difficult to do so since part of the product was welded. There are 12 different parts and 24 parts in total. The weight of the cam that we dissected was 52.5g. The cam that we dissected was an old design cam and has been used many times. Even though the weight is small, climbers carry a few cams, carabiners, chalk and nuts. All of these equipments add up to the weight that they have to carry when climbing. This is why reducing weight of our product is important but of course safety comes first. We performed FMEA, DFMA and DFE. FMEA for this product is crucial as mentioned before, a failure is fatal. From our FMEA, failure of the main cable and trigger wires are the most hazardous. The parts that usually fail first are the sling and the trigger wires. Because of this, we are thinking of integrating signs of wear or a detector to show if the product should be retired. From our DFMA, it shows that most of our products are machined and there are a few welding. So, in our DFE analysis, we suggested casting instead of machining as this will result in reducing waste of material. The welding can also be replaced by either redesigning our product without the need to weld. The products may be recycled by sending the product back to companies that sell them. After finishing these analyses, we are moving on towards research on the product and ideas for redesigning the product to fulfill the requirements that we have set earlier.
• You made an interesting observation that skilled climbers typically place, while less skilled climbers remove. Does this have any specific implications for the design?
• How is the design strapped to climber when not in use?
• We appreaciated your description of functionality, but we found it somewhat hard to understand without picture or diagram. The assembly photograph you included later was helpful, but we found it somewhat difficult to cross reference each part name.
• It was not clear to us what you concluded from your DFMA studies – Do you recommend any or all of the suggestions you made in the table?
• In your DFE analysis, you commented on the feasibility of recycling the product at its end of life. Do you think this is realistic? Where would our climbers take the product for recycling?
  • Ans: Recycling climbing cams are realistic. We have done some research and found out that retired cams can be returned to their manufacturers for research and recycling.
• In your FMEA we were surprised to not see any failures due to the climber attempting to force the equipment into a difficult crack, damaging it, or getting it snagged while attached to the climbers harness and not in use. Do you think these issues are unlikely or unimportant?
• A free body diagram would help in analysis of function and discussion of what happens in a fall. Please include such a diagram and a numerical analysis to get an estimate of the factor of safety and components that receive the most stress.

Additional Comments

It would be useful if the prefaces to each section contained a bit more generalized information, and if more conclusions were available in the executive summary and in the individual sections.

Revision

We received your revised first report, but we were not able to find your responses to our comments directly. We would like you to respond directly on the “discussion” page and let us know as soon as you do so. We found a force analysis in your second report, but a free body diagram of an individual cam, including reaction forces, normal forces, etc., would be helpful in analyzing the product, and we would like to see this analysis as part of the revised first report. Finally, there is no need to keep a separate “1st report” page, since the full page history is recorded on the wiki.