Now that your team has generated several ideas, it is time to identify strengths and weaknesses of each design to eventually produce a final sketch of your team's bioreactor.
For the alternatives that remain, list their strengths and weaknesses in relation to the design criteria. To make your decisions, you might have to do more research, testing each alternative and gathering data about its performance. These test results must be recorded and compared with results from other tests, so that fair and accurate decisions can be made about which solution is best.
Sometimes, the testing will suggest that, if you change one alternative slightly, or combine two or more alternatives, you will end up with a better solution. The design improvements can lead to better performance, increased safety, and lower cost. In this phase, the design is critically examined by noting how other designs perform to see how it can be improved.