Interview Questions › Product Design

Design a child safety wearable for amusement parks

Design a child safety wearable wristband and mobile companion system for parents visiting crowded theme parks, festivals, and public zoos.

Context

Over 2,000 children get separated from their parents daily in large theme parks, creating sheer panic for parents and operational delays for park security.

Clarifying questions to ask first

• Is this a park-rented wristband or a personal consumer device brought from home? (Park-issued rental linked to park ticket app).
• How long must the battery last? (Min 24 hours on single charge).

How to approach it

1. Identify User Needs: Parents (instant location tracking without battery anxiety, geo-fence alerts), Children ages 3-10 (comfortable, waterproof, tear-proof, fun to wear), Park Staff (fast child identification and reunification)
2. Design Hardware & Connectivity Constraints: GPS + Ultra-Wideband (UWB) for precise indoor/crowd localization, NFC tap badge for park staff, child-proof clasp that cannot be pulled off accidentally
3. Design Companion App & Real-Time Safety Features:
4. 1. "Digital Leash" Dynamic Geofencing: Alerts parent phone immediately if child moves >20 feet away in a crowd
5. 2. Augmented Reality "Find My Child" Camera Compass (shows directional arrow overlay pointing through crowds)
6. 3. Park Security Emergency Beacon: Instantly broadcasts child photo and last-known location to all park security gates
7. Define privacy, data encryption, and battery longevity standards

Framework: User Personas (Parent, Child, Security) -> Physical Wearable Hardware Design -> Connectivity Architecture (UWB/BLE) -> Software Emergency & AR Guidance -> Safety Metrics

Sample answer

• GPS fails in dense crowds and indoor pavilions; Ultra-Wideband (UWB) is required for directional sub-meter precision
• Wristband must be impossible for a toddler to unbuckle without a parent key or dual-pinch clasp

1. MVP: Waterproof silicone UWB wristband, dynamic proximity bluetooth leash, AR camera locator, and 1-tap "Child Lost" security dispatch trigger

Executive design: A durable UWB child wristband paired with an AR directional mobile locator, dynamic proximity geo-fencing, and instant park security emergency dispatch.

What interviewers look for

• Hardware Durability & Child Clasp Ergonomics
• UWB & Sub-Meter Crowd Tracking Precision
• Parent Mobile UI & AR Directional Guidance
• Child Privacy & Data Purge Security