Product Improvement and Design Documentation

Introduction
At this point in the design process, you should have a conceptual design that is justifiably the best potential solution that has been considered to address your design problem. However, just solving a problem will not automatically make a product commercially successful. The cost of development and production, government regulations, and product competition can create an environment in which the anticipated product sales will not support the development of the product. Other product characteristics that are more difficult to measure can also significantly affect the success of a product. Some of these qualitative considerations include product safety and potential liability, the global market and economy, the potential for other uses of the product, and the social trend toward environmental awareness and sustainability.
In this activity your team will assess your preliminary conceptual design with respect to a variety of factors that could affect its commercial success. Based on the results of your assessment, your team will optimize your design and create CAD working drawings that will be used to create a prototype.
Equipment
  • Engineering notebook
  • Internet access
  • Solid modeling software
Procedure
Following is a list of some factors that may affect the commercial success of your product. Keep these factors in mind as you create detailed documentation of your design.
  • Function. Can you simplify the operation of the product? Will the product function properly every time it is used?
  • Aesthetics. Can you improve the visual appeal of the product? Keep your target market in mind.
  • Ergonomics.Is the product well suited for human use? Is it user-friendly? Can you improve the ease of use?
  • Safety. Is the product safe to use? Are there any components that may pose a hazard?
  • Cost. Can you reduce cost by using alternate materials or reducing the amount of materials in the design? Can you change the design to simplify the manufacturing or assembly process of the product?
  • Standardization. Can you use standard tools and parts instead of requiring custom tools or parts?
  • Quality Control. Are there parts or components of the product that will be difficult to manufacture correctly? Can you alter the design to better control the quality of the product in the manufacturing stage?
  • Ease of Maintenance. Is the product easy to maintain? Can you improve the product to reduce the need for maintenance? Can the cost of maintenance be reduced by altering the design to require less expensive tools or parts in order to properly maintain the product?
  • Durability. Will the product function properly for the duration of its design life with minimal maintenance? Can the product be designed such that all components wear out simultaneously as it reaches the end of its design life?
  • Environment.Consider the lifecycle (as discussed in Lesson 1.1) of your product.Is the manufacturing process harmful to the environment or employees involved in the manufacturing process? Does the manufacturingprocess produce excess waste or hazardous material? Will disposal of the product emit toxins? Can the product or components of the product be reused or recycled? Can you reduce the overall impact of the product on the environment?
  1. Assign individual responsibilities among team members to complete each of the following tasks.
  2. Based on the concept sketch of the selected solution, create detailed annotated sketches of each part of your design in your notebook. Each group member should review every part drawing to ensure compatibility with other parts and adherence to the approved design scheme. Obtain the signature of each group member on each part sketch to indicate approval of the part.
  3. Create a 3D computer model of your proposed design.
  4. Create a set of CAD working drawings todocument your team’s proposed design. The drawing set should include dimensioned part drawings and assembly drawing(s) as necessary. Include all necessary dimensions, material callouts, notes, a parts list, and details necessary to construct a prototype of the product.
  5. Assign each of the factors listed above to a team member – each team member will be responsible for two or more assigned factors. Make a copy of theworking drawings for each team member, plus an extra copy for the next part of this activity. Each team member will then assess the product design with respect to assigned factor(s). Make notes and revisions to the drawings as necessary to document suggested improvements to the product. Keep these marked up prints as documentation.
  6. As a team discuss all of the suggested improvements and decide which improvements will be implemented. Mark up a clean set of working drawings to indicate your final design decisions. Obtain the signature of all group members on the mark up to indicate approval of the design changes.
  7. Revise the CAD model and drawings as necessary to reflect the approved changes. Print a set of revised working drawings.
  8. Complete a peer review of the entire drawing set. This should be documented with a set of marked up prints. To mark up the drawings, at least one member of your team must review each view, table, list, note, etc. on the drawing. Every item included on the drawings should be highlighted (usually yellow) if it is correct or corrected with a red pencil if it is incorrect. The checker should initial each drawing. It is a good idea to have every member of the team review each of the final drawings.
  9. Estimate the cost to produce one prototype of your proposed design according to the drawings. The cost should include the cost of materials (including raw materials, fasteners, and purchased components or subassemblies) and labor needed to build the prototype. Although a thorough cost analysis would consider other costs related to taking the product to market (such as manufacturing equipment, distribution, marketing, overhead, and selling the product), we will restrict our analysis here to material and manufacturing labor costs.
  10. Research and document the cost of each component of your design. Revise the parts list within your working drawings to include a column for cost. Input an estimated cost for each part.
  11. Estimate the time necessary to construct your prototype and an hourly wage for a person to assemble the product. Use these estimates to approximate a total cost of labor to build the prototype.
  12. Approximate the production cost for your product by summing the material cost and labor cost.
Conclusion
  1. What other design factors could be considered to improve your team’s design? How would you change your design to achieve this goal?
  1. Why is it important for every member of the team to be involved in the implementation of design changes?
  1. How can a 3D model improve a product design? Did your design change as a result of information gained from the 3D model of your product?
  1. How will the cost of production change from your estimate for the cost of a prototype if your product is mass produced? What factors (in addition to raw materials and labor) will affect production cost?

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Engineering Design and Development Component 2 Product Improvement and Design Documentation – Page 1