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| Your first design
challenge will be to design a layout for a spacecraft
cabin, but where do you start? How does an engineer go
about creating, evaluating, improving, and implementing a
design? The following discussion takes you through the
steps. You will use these steps with each of the design
challenges in SpaceCAD.
Step 1. State the problem. The first step is to describe the problem you are trying to solve in your design. What are you trying to accomplish, and what are the specifications and limitations you need to follow? The original Redstone rockets used in the Mercury Program had a limited payload capacity. This means they were limited in the amount of weight they could lift into space. Consequently, the original Mercury spacecraft was very small. For the purposes of this exercise, assume you have only one cubic yard for pilot space. Your single person spacecraft needs to accommodate everything an astronaut would need in a 6-hour mission. The astronaut needs to be able to navigate the spacecraft; monitor its progress, condition, and position; communicate with mission control and be securely restrained to prevent injury during takeoff and landing. The original capsule, which you drew in Lesson 6, was about 11 feet in length and 6 feet in diameter.
Mercury capsule dimensions
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 | How much space do you have in the capsule for necessary equipment? |
| Which items need to be within quick reach? |
| Which items need to be visible at all times? |
| What is a breakdown of how the astronaut will spend his/her time during the 6-hour mission? |
Step 3. List resources for information you need. List Internet URLs, books, articles, and resource people.
Here are some pictures we found that you could use to help you with this design problem. Search the NASA web site for additional information to help you with your design.
Mercury Instrument Panel
Click picture for larger view.
http://www.hq.nasa.gov/office/pao/History/diagrams/mercury2.gif
Interior view of crew station
Click picture for larger view.
http://www.hq.nasa.gov/office/pao/History/diagrams/mercury7.gif
Mercury Interior Layout
Click picture for larger view.
http://www.hq.nasa.gov/office/pao/History/diagrams/mercury1.gif
Step 4. Write down all the useful information you get from the above resources here.
Step 5. Use CAD or pencil and paper to sketch ideas. At this point you should be simply brainstorming, not creating the final design. So do not eliminate any of your initial ideas yet.
Step 6. Of the solutions you sketched in Step 5, which are your 3 best? Describe them here. Also, list their relative strengths and weaknesses as solutions to the problem.
Step 7. Select your best solution and explain why it was the best.
Step 8. Give details about how you will construct the solution you chose. Include a detailed CAD drawing and step-by-step description. Include dimensions.
After you have completed steps 1-8, you would be ready to start construction of the solution. Since this is a CAD web site, we will not be completing construction steps. However, if you were really building the solution you would
| Construct a prototype |
| Devise a testing plan to see how well the solution works |
| Report results of the testing |
| Evaluate how well the design met the solution requirements |
| Write a report to describe strengths and weaknesses of the solution discovered through testing |
| Develop ideas for improvements |
If the solution was not successful, you could start the design process over. You might decide to improve the design, go back and try one of the alternative ideas from step 5, or start back at step 1 by refining the problem statement.
Ready for your first design challenge? Don't be limited by the actual design of the capsule. Use your imagination, but work within the constraints of the problem (Step 1). When you have completed your design, please share it with us. Email your .cad, .jpg or .gif file to us.