The design process practice questions.

A student has six weeks of a design project left. The current plan allocates four weeks to generating further concepts, one week to making a prototype and one week to writing up. Nothing has been made yet and no user has tested anything. Which single change to the plan best serves an iterative process?

• Shorten the write-up week to allow a second week of concept work
• Replace the making week with a computer rendering of the final concept
• Move two of the concept weeks into making and user testing
• Keep the plan as it stands and record the missing tests as a limitation

Answer: Move two of the concept weeks into making and user testing

An iterative process needs at least one made and tested version before the outcome is fixed, so hours spent making and testing buy evidence that a fifth week of sketching cannot. Recording the missing tests as a limitation documents the failure instead of preventing it, and a rendering cannot be handled by a user.

A team is drafting the specification for a folding walking stick. Which of the four statements below can be objectively tested on the finished product?

• The product must appeal to environmentally conscious young buyers
• The product must feel comfortable to hold for long periods
• The product must look modern alongside competing products
• The handle must withstand a 250 N pull without permanent set

Answer: The handle must withstand a 250 N pull without permanent set

A specification point is testable only if it names a quantity, a unit and a pass condition, so a stated pull force with no permanent deformation can be checked on a rig. Appeal, comfort and appearance are stated as opinions and would need to be rewritten with a measurable proxy such as a rated score from a user panel.

After a first round of testing, a team alters the latch geometry of a lunch box, retests the modified box with the same users on the same tasks and rechecks every point of the specification, then repeats the whole modify-and-retest loop twice more. Which characteristic of the design process does this show?

• Iteration - repeating a cycle to refine the solution
• Standardisation - reusing an agreed component across products
• Optimisation - tuning one variable towards its best value
• Validation - checking that a product meets a legal standard

Answer: Iteration - repeating a cycle to refine the solution

Iteration means running the same test-modify-test loop again so that each version is measured against the previous one under identical conditions. Changing the users or the tasks at the same time would destroy the comparison the loop depends on.

A team has agreed a measurable specification for a bicycle lock with its client and has not yet drawn anything. Which activity normally comes next in an iterative design process?

• Writing the design brief with the client
• Generating a range of initial concepts
• Carrying out the final evaluation against the criteria
• Ordering the production tooling for the body

Answer: Generating a range of initial concepts

The specification defines the target, so the next move is to open out the solution space with several competing concepts before narrowing down. The brief precedes the specification, and evaluation and tooling both depend on a chosen solution that does not yet exist.

A council states that a new bus shelter must be installed within a footpath 2.4 m wide and must not exceed a stated capital budget. Within the design process, these two statements are best described as which of the following?

• Aesthetic criteria for the final concept
• User needs gathered from primary research
• Constraints that limit the solution space
• Evaluation criteria applied only after manufacture

Answer: Constraints that limit the solution space

Constraints are fixed limits inside which every acceptable solution must sit, so a concept that breaches them is discarded rather than scored. Criteria, by contrast, are qualities on which competing concepts are compared.

At the end of a development phase a team scores its prototype against every numbered point of the specification and records which points the prototype fails. What is the main purpose of this activity within an iterative process?

• To demonstrate to the client that the original brief was correct
• To replace the need for user trials with the final product
• To establish the selling price of the finished product
• To decide which parts of the design need a further iteration

Answer: To decide which parts of the design need a further iteration

Evaluation against the specification is diagnostic: the failed points identify exactly where the next loop of development must be directed. Treating it as a final verdict removes the feedback that makes the process iterative.