Hunter Safety Lab’s IRIS Detect technology uses an infrared laser to detect the reflective strip found on high-visibility safety vests.
IRIS Detect is a vehicle-mounted infrared laser sensor that can detect the retro-reflective strip on standard Class II and III high-vis apparel. The major advantage of IRIS Detect over most other industrial pedestrian detection systems is that it does not require ground-personnel to carry an electronic tag, or change their behaviour in any way.
IRIS (“Infrared Retroreflector Identification System”) is a patented technology developed by Hunter Safety Lab. IRIS sensors continuously emit pulses of non-visible laser into blind-spots around the machine. The driver receives an audio-visual alert when someone is detected in the blind-spot.
Detection range and field-of-view
IRIS Detect has been optimised to detect ground personnel working near mobile plant, and features a 60 x 45 degree detection area, with a 10 metre (30 feet) detection range.
Multiple sensors can be used to create coverage zones tailored to particular applications. For example 3 sensors can provide full 180 degree coverage behind a vehicle. Depending on the application requirements, the detection start and finish distance can be configured to lie anywhere within the 1 to 10 metre detection range.
Detection ranges up to 150 metres are possible by designing the sensor to have a narrower field of view.
IRIS Detect uses a high-spec pulsed laser diode to provide reliable detection performance under all lighting conditions, from complete darkness to intense glare from the sun on wet pavement.
Standard Class II safety vests typically have a total of about 3000cm2 (465in2) of reflective strip applied to them. The IRIS Detect sensor requires a minimum of approximately 75cm2 (11.6in2) of reflective material within its field of view. This enables reliable detection even when the person is in a sub-optimal orientation such as side-on or crouched down.
Safety and compliance
IRIS sensors comply with relevant US and EU standards including Class-IM laser eye safety, EMC, REACH, ROHS.
The sensor has no moving parts and can withstand the shock and vibration associated with heavy machinery. The IP69K rated enclosure ensures complete weather resistance for year round operation, including during wash-down.
In-cab control box
The in-cab control-box provides an audio-visual alarm to the operator and, if interlocked, can automatically stop or govern the machine. The control-box can log details such as detection distance, direction and time. This data can be analyzed by site safety managers to provide information about the quantity and type of human/machine interactions for that machine.
If desired, video cameras can be integrated into the IRIS Detect system to record detection events as they take place. Automatically triggered by a detection, the video camera saves a 1 minute segment of footage around the event for later analysis. This feature offers heath and safety managers a unique opportunity to capture and review close calls that would otherwise go unreported.
Retroreflectors are materials that have been engineered to reflect light back to the source. Common examples are the grey glass-bead reflective strip found on constructions vests, and the high performance micro-prismatic reflective material found on road signs.
Reflective apparel will often be the most common reflector on a work site, but care needs to be taken to minimise the frequency of unwanted detections from sources such as road cones and road signs. Unwanted detections undermine the system’s effectiveness and can be minimised by:
- Mounting the sensor high and angling it towards the ground,
- Setting the cut-off distance to the minimum effective range,
- Aligning the sensor so its field of view covers only genuinely hazardous areas,
- Using non-reflective road cones if permitted,
- Activating sensors in context, e.g only activate the rear sensors when reverse gear is engaged,
- Applying visually transparent infrared blocking film to any problem reflective sources.