THE CHALLENGEWhen a Worker Is Alone, the Device Has to Raise the Alarm Itself
A lone worker who collapses, falls, or is incapacitated cannot press a button. By the time anyone notices they are missing, minutes or hours have passed. A safety device for this role has to detect the incident on its own through fall and no-motion sensing, escalate through a defined chain, and hold a voice connection even on a marginal network. The device and the platform behind it are designed around the timing, false-alarm handling, and compliance evidence that make it usable on a real site.
One layer of the full Telematics and GPS Tracking platform, working closely with People Tracking Solutions.
WHAT'S INCLUDED
Detection, Escalation, and Voice in One Wearable
Man-Down and Fall Detection
Accelerometer and gyroscope data are fused on an STM32 low-power MCU to detect impacts, slumps, and loss of orientation. Detection thresholds are tuned per work type so a genuine fall fires while normal bending and crouching do not.
No-Motion and Tilt Timers
Configurable no-motion and prolonged-tilt timers run on the device. If the worker stops moving for the set window, the device pre-alarms locally, gives them time to cancel, then escalates if there is no response.
One-Touch and Discreet SOS
A dedicated SOS button uses a press-and-hold pattern that avoids accidental triggers, with a discreet activation option for situations where the worker cannot be seen reaching for a device.
Two-Way Voice
A speaker and microphone pair with a cellular voice or VoLTE path so a responder can talk to the worker the moment an alarm fires, assess the situation, and stay on the line until help arrives.
Scheduled Check-In
Periodic check-in prompts let the worker confirm they are safe at set intervals. A missed check-in escalates automatically, covering risks that fall and motion sensing alone would miss.
Monitoring Platform
A backend and operator console receive alarms, show worker location and status, run the escalation chain to supervisors or an alarm receiving centre, and keep a full incident log for compliance.
WHEN AN ALARM FIRES
The Few Seconds That Matter
The whole design exists for the moment something goes wrong. That sequence is engineered carefully so a real incident is escalated fast, a false alarm can be cancelled, and the worker is never left wondering whether the device worked.
Local Pre-Alarm
The device vibrates and sounds a local pre-alarm first, giving a conscious worker a short window to cancel. This is what keeps false alarms from flooding the monitoring centre.
Escalation Chain
If not cancelled, the alarm escalates through your defined chain with location attached, from supervisor to control room to alarm receiving centre, until someone acknowledges it.
Voice and Location
The responder gets the worker last known position and can open two-way voice immediately, turning an anonymous alert into a real conversation about what help is needed.
HOW IT WORKS
Sensor to Responder
On the Device
An STM32 MCU runs the fall, no-motion, and tilt logic in firmware under FreeRTOS. A Quectel cellular module handles LTE data and voice, with GNSS for position. The firmware manages alarm state, cancel windows, and the cellular link.
Over the Air
Alarms and telemetry travel over a TLS-secured channel to the platform, with voice on a parallel cellular path. The link is designed for marginal coverage with retries, store-and-forward, and a fallback SMS alert if data fails.
In the Platform
The backend ingests alarms, drives the escalation state machine, surfaces the incident on the operator console with location and worker profile, and records every step for the compliance log.
RUGGED AND COMPLIANT
Built for the Site and the Audit
A lone worker device lives on a belt or lanyard in dust, rain, and impact, and it has to produce evidence that the duty of care was met. The hardware and the records are designed for both.
Rugged Enclosure
IP67 sealing and impact resistance are targeted so the device survives drops, dust, and wet conditions on industrial and outdoor sites.
Battery for the Shift
Power is budgeted so the device covers a full shift with detection, periodic location, and headroom for an alarm with voice, with predictable low-battery warnings.
Incident Evidence
Every alarm, cancel, escalation, and voice session is timestamped and logged, giving you the record needed to demonstrate lone worker duty of care.
FAQ
Common Questions
How does the device avoid constant false alarms from fall detection?
Fall and no-motion thresholds are tuned per work type, with a local pre-alarm and a cancel window. The device vibrates and sounds before it escalates, so a worker who simply bent down or sat still can dismiss it. Only uncancelled events reach the monitoring centre.
What happens if the worker is unconscious and cannot cancel?
That is the core case the device is built for. Fall, no-motion, and tilt detection fire without any user action. If the local pre-alarm is not cancelled within the window, the alarm escalates automatically with the worker location through the defined chain.
Does it work where cellular coverage is weak?
The link is designed for marginal coverage. Alarms use retries and store-and-forward, with an SMS fallback if the data path fails. Two-way voice uses the cellular voice path, and the device reports last known good location when live position is unavailable.
Can it connect to your alarm receiving centre or control room?
Yes. The escalation chain routes alarms to your supervisors, internal control room, or a third-party alarm receiving centre, and APIs are exposed so the platform can integrate with an existing monitoring operation.
How long does the battery last?
Power is budgeted for a full shift including continuous detection, periodic location, and reserve for an alarm with two-way voice. The device gives predictable low-battery warnings so a worker is never caught with a dead device mid-shift.
Is the device built alongside the software?
Yes, both are in scope. The wearable hardware, the firmware running the detection and alarm logic, and the monitoring platform form one system, which is what keeps the timing of detection and escalation tight and consistent.
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