How do you compare design alternatives?

1 Define objectives and criteria

The first step in comparing design alternatives is to define the objectives and criteria that you want to achieve and measure. Objectives are the overall goals that you want to accomplish, such as maximizing fuel efficiency, minimizing noise, or enhancing safety. Criteria are the specific metrics that you use to quantify and compare the objectives, such as fuel consumption, decibel level, or failure rate. You should also assign weights to the criteria according to their importance and relevance.

2 Generate alternatives

The next step is to generate a set of feasible alternatives that can meet the objectives and criteria. You can use various methods to generate alternatives, such as brainstorming, sketching, modeling, or simulation. You should consider different aspects of the design, such as geometry, materials, propulsion, control, and configuration. You should also explore the trade-offs and constraints that each alternative entails, such as weight, cost, complexity, and reliability.

3 Evaluate alternatives

The third step is to evaluate the alternatives based on the criteria and weights that you defined. You can use different tools to evaluate alternatives, such as analytical methods, numerical methods, or experimental methods. Analytical methods use mathematical formulas and equations to calculate the criteria values. Numerical methods use software and algorithms to solve complex problems and simulate the behavior of the alternatives. Experimental methods use physical tests and measurements to validate and verify the alternatives.

4 Compare alternatives

The final step is to compare the alternatives and rank them according to their performance, cost, and feasibility. You can use different techniques to compare alternatives, such as scoring, ranking, or decision matrices. Scoring involves assigning numerical values to each alternative based on the criteria and weights. Ranking involves ordering the alternatives from best to worst based on the scores. Decision matrices involve displaying the scores and rankings in a table or a graph for easy visualization and analysis.

5 Adjust and iterate

Comparing design alternatives is not a one-time process, but an iterative one. You may need to adjust and refine your objectives, criteria, weights, alternatives, and evaluation methods as you learn more about the problem and the solution space. You may also need to consider other factors, such as stakeholder preferences, ethical implications, or environmental impacts. You should always review and validate your results and assumptions, and seek feedback and input from experts and peers.

6 Choose the best alternative

After comparing design alternatives, you should be able to choose the best one that meets your objectives and criteria, and satisfies your constraints and requirements. You should also be able to justify and explain your choice, and document your process and rationale. Choosing the best alternative is not always easy or obvious, but it can be rewarding and satisfying if you follow a systematic and objective approach.

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?