Decision Matrix
The purpose of this wrench is to make it easier to assemble and remove the fuel pump from a VP-44 Cummins ISB 24-valve diesel engine. This would improve the efficiency and frustration of working on these engines.
This assignment covers the specific components of the wrench. Two assignments ago I created modules of motion for the wrench. This consisted of exploring different hinge options, exploring their strengths and weaknesses
through a multidimensional comparisson of each module. Last assignment I chose the best module for the wrench using a decision matrix to find the best option. Once I discovered the best module I created
detailed models of the tool components including the selectred module. Using knowledge from my solid mechanics course I calculated normal stress, Bearing stress, Shear stress, Hooke's Law, and safety factor and chose
a material that satisfies the dimensional, corrosion, and strength requirements. This assignment I created a decision matrix to compare the strengths and weaknesses of each component. Afterwards I finished modeling the
components then created drawing files. I made sure to keep dimensions and tolerances in mind when drawing to ensure the person using them could follow appropriately.
The wrenches will be used at a constant rate of 1 rad/s, will accept 15mm bolts, are no longer than 10 inches, and are made of a Chromium Vanadium alloy drop forged and plated in chrome. The moment about the hinge
will be calculated to help determine necessary strength at this locati n. I will also calculate normal, bearing, and shear stresses aswell as strain and safety factor to determine the validity of my chosen steel.
I am assuming the material properties listed on the material sheet aswell as the forces calculated in the static analysis sheet. After completing these calculations I can finally complete my drawings and finish
detailing a plan of acton for constructing this tool. From this I can create a bill of materials including part number, material, part name, description, and quantity.
The decision matrix works with a score of 3 being the best and a score of 1 being the worst. Its purpose is to help me understand how well the
components I designed match up to the criteria for an optimum tool. The criteria I chose were cost, durability, manufacturability, and functionality.
The two biggest ones were cost and manufacturability which go hand in hand, With durability and functionality being aspects of a good tool, weighted
accordingly. Cost and Manufacturablity go hand in hand on this tool because everything is made of the same material, cost only varies as the need for
more processing and machining increases.
The best component design was the handle, it had the best everything besides functionality. This is mostly because it is the easiest to manufacture
and sees the least amount of wear compared to the other componenets. The Hinge component had a score of 2 exactly it was in the middle between the handle
and head on evry criteria. This part is fairly difficult to manufacture and sees some wear but not as much as the head. The Head scored the least out of
the three with a score of 1.4. This is because this part is the hardest to manufacture requiring alot of post processing. This component also sees the most
amount of wear and is the most functional because it is the working end of the tool.
I learned that that it is important to think about the bigger picture, I made the mistake of thinking too narrowly
which made making three concepts for each assignment very detail oriented making this assignment unnecessarily difficult. If I were to
change something I would have been less specific with my concepts in the last assignment. I also learned how to use
creo more efficiently and creatively. It took me a while to relaern how to do drawings but I feel much more confident with
it now. I also learned that if i ever find myself stuck I should google my problem as it could have saved me hours of time in the past.
To Advisee Antonio Kraychete
Overall very good job, the presentation is clear, simple, and to the point. Maybe you could make your Description under yourTo Advisee Daniel Todd
The organization of your website is very good, simple and to the point. Maybe next time you could make your design images