Free vocabulary hub
Criteria, constraints, and the engineering design loop
Good design starts with the real problem and the people it serves. NASA and JPL education materials pair criteria with constraints; Stanford d.school frames problem framing and user-centered design.
Deciding what challenge you are really trying to solve before you build—clarifying the need, the user, and the situation rather than rushing to a gadget idea.
Real-world extension: Poor problem framing often leads to elegant solutions for the wrong problem.
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Keeps the needs of specific people in view while creating a solution—understanding and responding to real users instead of assuming everyone wants the same thing.
Real-world extension: Shapes accessibility tools, apps, medical devices, and classroom products.
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The features that define success in a design problem—strength, accuracy, usefulness, comfort, or other goals a solution should meet.
Real-world extension: Engineers prioritize criteria because no design can maximize everything at once.
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The limits a design must work within—time, cost, size, materials, or environment. Real design always involves both criteria and constraints.
Real-world extension: Spacecraft, bridges, and consumer products all face strong constraints that shape what is possible.
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Generating many possible solutions before one is selected. Variety increases the chance of finding an effective path forward.
Real-world extension: Professional teams use structured brainstorming to compare concepts before expensive builds.
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A simplified representation of an idea, object, or system that helps you think and test before building the full version.
Real-world extension: Wind-tunnel models, 3D simulations, and scale prototypes all serve this role in engineering.
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An early version built to learn from, not just to impress—used to discover strengths, weaknesses, and next-step questions.
Real-world extension: Prototypes can be physical, digital, or even “no-build” experiences that test an idea quickly.
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Trying a model or prototype deliberately to gather evidence about how it performs, often with controlled variables and fair comparisons.
Real-world extension: Testing in real engineering ranges from classroom load tests to spacecraft vibration and thermal tests.
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The cycle of making, testing, improving, and trying again. Improvement usually comes through repeated rounds, not a single pass.
Real-world extension: Standard in aerospace, robotics, games, and product development.
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When improving one feature makes another harder to maximize—such as stronger but heavier.
Real-world extension: Trade-offs appear everywhere: battery size vs. weight, speed vs. safety margins.
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