Interview Questions › Product Design

Design the core interaction model and spatial OS for everyday AR smart glasses

Design the spatial user interface, interaction paradigm (eye tracking + micro-gestures + voice), and notification glanceability for lightweight, all-day wearable Augmented Reality (AR) glasses.

Context

Heavy VR UI concepts (giant floating 2D windows, reach-and-grab hand waving) cause arm fatigue ("gorilla arm"), social embarrassment in public, and obscure real-world peripheral vision.

Clarifying questions to ask first

• What is the field of view (~50° diagonal FOV in a standard optical waveguide frame)?
• How are interactions performed without looking weird in public? (Subtle finger micro-gestures on an EMG neural wristband).

How to approach it

1. Design Principles for All-Day Wearable AR: "Glanceable & Ephemeral", "Zero Social Embarrassment in Public", "Zero Occlusion of Real-World Safety Hazards", "Minimal Battery & Thermal Footprint"
2. Design Multi-Modal Spatial Interaction Paradigm:
3. 1. "Micro-Hand Gestures via EMG Wristband" (Subtle finger taps in pocket or by hip: index-to-thumb tap selects, thumb-swipe scrolls with zero arm raising)
4. 2. "Eye-Gaze Intention Detection with Dwell Suppression"
5. 3. "Contextual Peripheral UI Anchoring" (Notifications appear subtly in upper peripheral vision and dismiss automatically when looking away)
6. 4. "World-Anchored Spatial Holograms" (Turn-by-turn walking arrows painted onto physical pavement; translations pinned directly over foreign signs)

Framework: Spatial Wearable Constraints -> Multi-Modal Input Hierarchy (EMG Micro-Gestures + Gaze + Voice) -> Glanceable UI State Machine -> Environmental World-Anchoring -> Public Usability Metrics

Sample answer

• Raising hands in the air to swipe virtual screens is fatiguing and socially awkward; EMG wristband micro-gestures by the side of the leg provide discreet, effortless control
• Notifications must be contextual and ephemeral, vanishing the instant real-world attention is required

1. MVP: Gaze + EMG finger-pinch micro-interaction, glanceable heads-up notifications, world-locked pedestrian AR navigation arrows, and live optical sign translation

Executive design: A discreet spatial operating system for AR glasses powered by eye-gaze targeting, imperceptible EMG finger micro-gestures, and context-aware ephemeral holograms.

What interviewers look for

• Gorilla Arm Prevention & Micro-Gesture Ergonomics
• Field-of-View (FOV) Information Density
• Real-World Safety & Visual Distraction Mitigation
• Context-Aware Environmental AI (Multi-Modal Vision)