Product design question
How do you design a Roomba vacuum for the stairs?
- Product design
- Hard
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What this question tests
Physical product design under a real engineering constraint, checking whether you can identify why the current gap exists and propose a grounded, safety-first solution.
How to approach it
- Define the constraint: current robot vacuums avoid stairs entirely using drop sensors, since falling down stairs is both a safety and cost risk.
- Identify the user need: households with stairs currently need a separate vacuum or manual cleaning for stairs, since no consumer robot handles them.
- Weigh the engineering trade-off: a stair-capable Roomba needs new locomotion, like tracked wheels or a hopping mechanism, and much more sophisticated balance and fall-prevention sensing.
- Prioritize safety above all, since a malfunctioning robot on stairs risks damage or injury far more than a flat-floor model.
- Propose a phased design: start with a robot that can climb a single step safely with tracked wheels and multi-point contact sensing, rather than attempting a full staircase immediately.
- Define success as safe single-step traversal rate in testing and, eventually, full staircase completion without falls, validated over thousands of test cycles before any consumer release.
What a strong answer includes
- Explains why current Roombas avoid stairs entirely, drop sensors and fall risk, rather than assuming this is a trivial feature gap.
- Proposes a phased engineering approach, one step first, rather than promising full staircase capability immediately.
- Prioritizes safety validation with a concrete testing bar, thousands of cycles without failure, appropriate for a safety-critical feature.
Common mistakes
- Proposing a full staircase-climbing robot without acknowledging the significant safety and engineering challenges involved.
- Ignoring why current robots deliberately avoid stairs, treating it as an oversight rather than a deliberate safety trade-off.
Likely follow-up questions
- How would you test for safety before allowing this near real staircases with pets or children?
- What would be your minimum viable version of this feature?
More product design questions
- Design a TV for a car.Google · Product design · Hard
- Design a refrigerator for the blind.Google · Product design · Hard
- How do you design a camera for the elderly?Google · Product design · Medium
- Redesign Twitter for eCommerce.Shopify · Product design · Hard
- How would you go about designing a new location sharing app for Google?Google · Product design · Medium
- How would you improve Google Home?Google · Product design · Easy
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Learn the skill behind it
Chapters of the AI PM course that teach what this question tests.
- Chapter 4: Discovery and strategy for AI products
- Chapter 7: AI UX and human oversight: design for a system that is wrong sometimes
- Chapter 14: Get the job: the AI PM interview loop