The Laser scanner (Active Opto-electronic Protective Device responsive to Diffuse Reflection) measures the distance between the objects that fall into its sensing field by means of the small fraction of energy that is re-diffused by the objects themselves in axis with the direction of emission.
AOPDDRs do not need a cooperating target for their operation, especially where the protected area is mobile, as is the case with AGVs, or where it is necessary to vary the position and size of the protected area during the production process.
For EN 61496-3, Laser Scanners must be classified in accordance to type 3 or lower safety sensors.
Using the Safety Laser Sensor, precise programmable horizontal protected areas of variable shape can be created (i. e. semi-circular, rectangular or segmented), suitable for all applications with no need of a separate reflective or receiving element.
It is also possible to use the Laser Scanner in a vertical position for the access protection to a dangerous area, in that case detection of the edge of the gate is mandatory (IEC TS 62046).
Any person or object entering or remaining in the safety zone during survey causes, through the self-monitored static safety outputs of the device, an emergency stop command to the control system of the protected machine. The machine’s hazardous movement will thus be interrupted.
If the warning zone is instead occupied, thanks to a non-safety dedicated solid state output, a signal is sent to the machine control system, which can be used to activate a light or a sound signal in order to prevent operators to break into the safety zone and stop the machine. Or, on an AGV application, the warning signal can be used to slow the vehicle down, so that a possible further break of the safety zone will not force it to stop abruptly, thus reducing the mechanical wear of the AGV.
The profiles of the controlled areas, as well as all the other configurable parameters, are programmable through a dedicated user interface software, installed on a laptop or PC and connected with the scanner via a serial interface.
The Laser Scanner is also able to automatically detect the controlled area by means the teach-in function.
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