The challenge
Enterprises needed a simple way to screen for elevated body temperature at entry points and production floors while keeping queues short and preserving privacy. Operations teams wanted a compact device, easy onboarding, and clear alerts only when action is needed.
Goals
- Fast contactless screening
- Minimal false positives
- No touch onboarding and updates
- Event only notifications with role based access
The solution
SequoiaAT designed a palm sized wall mounted device that pairs a thermal sensor with a compact optical module. The system processes thermal frames continuously. When an elevated event is detected, the optical module captures a frame and the device prepares an event package for alerting authorized managers.
Calibration profiles and alignment values are stored in non volatile memory so firmware can be re flashed without losing tuning. The device supports secure OTA and can roll back if the new image fails checks.
Core capabilities
- ESP32 platform with FreeRTOS tasks for scan, web, Wi Fi, and updates
- Circular queue interface between capture tasks and AI module
- Configurable recipients for event emails
- AP mode for first time setup from mobile
How it works
- Init task sets up sensors, Wi Fi, and peripherals
- Thermal task scans continuously and detects an elevated event
- Optical task captures a frame and enqueues both frames
- AI module dequeues, associates the subject, and prepares an alert
- Email is sent to the configured manager with necessary details
Security and privacy
- Event only capture of face image
- Retention policy controlled by the business
- Least privilege access and role based visibility
Phase 1
Single location, single device. Alert by email to managers when an event is detected. Pilot and validation.
Phase 2
Single location, multiple devices. Centralized configuration and monitoring.
Phase 3
Multi tenant fleet with secure provisioning, health dashboards, and audit trail.
Results
The pilot showed quick screening times and clear action signals for supervisors. The OTA path reduced downtime for updates. Storing calibration values in independent memory kept maintenance simple.
Where this fits
- Life sciences campuses Learn more
- Clean tech and industrial sites Capabilities
- IoT programs and device fleets Our IoT work
Why Sequoia Applied Technologies
- Embedded to cloud delivery with a product mindset
- Hands on device bring up, calibration, and field validation
- Privacy and security reviews as part of engineering
- Cross domain teams in AI/ML, mobile, and test automation
Deployment and next steps
- Site survey and mounting plan
- Network and onboarding checklist
- Manager notification setup and test run
- Privacy notice update and opt in flow as per policy
- Go live with monitoring and OTA rollout plan
