Description
The application of indoor crowd sensing to monitor and encourage physical separation between individuals — primarily for infectious-disease control. Social distancing compliance overlaps with contact-tracing (which records who got close to whom) but emphasizes real-time density and pairwise-distance estimation, often coupled with feedback signage or app notifications. This is the application context in which BLE proximity estimation and crowd-density-estimation gained their broadest attention during 2020–2022.
Why it's hard
- BLE pairwise-distance estimation is noisy at the relevant 1–2 m thresholds.
- Aggregate density bounds compliance only weakly — two people at 1.5 m in a low-density room is non-compliant.
- The framing is politically and behaviorally contested; consent and adoption are non-technical bottlenecks.
- Cross-modal fusion with crowd-monitoring systems is needed but rarely deployed cleanly.
Common approaches
- BLE-based pairwise proximity flagging.
- Camera + computer-vision pose-distance estimation as a high-accuracy baseline.
- Aggregate density thresholds with zone-level alerting.
- Mobile-app feedback consuming venue-deployed sensing.