How do you select the best design alternatives?

1 Design alternatives

Design alternatives are the different possible solutions that can meet the requirements and objectives of a given design problem. For example, if you are designing a new aircraft, you may have several alternatives for the wing shape, the engine type, the fuselage configuration, and so on. Each alternative will have its own advantages and disadvantages in terms of performance, cost, safety, environmental impact, and other factors.

2 Evaluation criteria

Evaluation criteria are the measurable or qualitative attributes that you use to assess the value and feasibility of each design alternative. They can be derived from the customer needs, the market demands, the technical specifications, the regulatory standards, and the project constraints. Some examples of evaluation criteria are fuel efficiency, noise level, payload capacity, reliability, maintainability, and customer satisfaction.

3 Evaluation methods

Evaluation methods are the systematic and logical procedures that you use to apply the evaluation criteria to the design alternatives and rank them according to their relative merits. There are different types of evaluation methods, such as analytical, empirical, experimental, and simulation-based methods. Some examples of evaluation methods are cost-benefit analysis, multi-criteria decision analysis, trade-off studies, sensitivity analysis, and optimization techniques.

4 Evaluation tools

Evaluation tools are the software or hardware applications that you use to support the evaluation methods and facilitate the data collection, analysis, and presentation. They can help you perform complex calculations, model physical phenomena, simulate operational scenarios, visualize results, and communicate findings. Some examples of evaluation tools are spreadsheets, databases, CAD software, CFD software, flight simulators, and virtual reality systems.

5 Evaluation process

Evaluation process is the sequence of steps that you follow to conduct the evaluation of the design alternatives and select the best one. It can vary depending on the scope, complexity, and stage of the design problem, but it usually involves the following steps: define the evaluation criteria and weights, collect and verify the data for each alternative, apply the evaluation methods and tools, compare and rank the alternatives, perform sensitivity and robustness checks, and document and justify the selection.

6 Evaluation challenges

Evaluation challenges are the difficulties and uncertainties that you may encounter during the evaluation process and that may affect the quality and validity of your results. They can arise from various sources, such as incomplete or inaccurate data, conflicting or changing criteria, subjective or biased judgments, computational or experimental errors, and ethical or social dilemmas. You should be aware of these challenges and try to overcome them by using reliable data sources, transparent and consistent methods, robust and flexible tools, and ethical and responsible practices.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?