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SICK LSI Technical Description - 06/98
3 How the LSI Works
Principle of Operation
The SICK LSI (Laser Scanner Interface) is an electronic
component with which you can interconnect one or more PLS
laser scanners to form one system and control them flexibly
according to the specific application. The LSI system is thus able
to monitor complex hazardous areas on a machine or vehicle.
Sensors, monitoring areas and monitoring cases
The LSI receives from the machine controls system certain input
signals, e.g. input A = low, input B = high. These signals activate
in the LSI one of the monitoring cases you configure using the
PLS/LSI user software.
The definition of each individual monitoring case stipulates which
monitoring area (consisting of a protective field and warning
field) is to be monitored on which of the connected sensors.
The active sensor, e.g. sensor 1, transmits the space contour it
sees to the LSI. The LSI compares the data received from the
sensor with the contour of the defined monitoring area.
Evaluation of a monitoring case in the LSI (simplified block diagram)
As soon as the LSI detects an object in the monitoring area, it
switches off the output configured for that case. In the example,
there is an object in protective field 3 and the LSI shuts off the
defined output OSSD A. This output signal is transmitted to the
machine controls system where it triggers a response, e. g.
EMERGENCY STOP.
Based on the monitoring cases, the LSI system can react flexibly
to various input signals and view various monitoring areas on the
sensors, according to application requirements. Up to two
sensors can be active at any one time under the same input
conditions (simultaneous monitoring cases).
Sensor 3
Sensor 4
Sensor 2
LSI
Input signals from
machine controls
system
(A = low, B = high)
Intrusion !
Shut-off signal to
machine controls system
e. g. EMERGENCY STOP
Defined
space contour
Object in area
Data
Sensor 1
Field 3
1
Inputs
A = low
B = high
Sensor
1
Field
3
Output
OSSD A
Monitoring case 2 active:
