Light Curtain Area Segmentation to Avoid Unnecessary Shutdowns
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing monitoring devices with light curtains often trigger unnecessary shutdowns when non-safety-critical objects pass through the monitored area, leading to system downtime and reduced availability.
Innovation Solution
A monitoring device with a safety controller and light curtain system that uses a function block to define configurable areas, enabling flexible muting and adaptive control of beam axes based on object size and type, ensuring only safety-critical interventions trigger shutdowns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the light curtain triggers a shutdown signal when an object interrupts the beam axes, then safety is ensured, but system availability decreases due to unnecessary shutdowns when non-safety-critical objects pass through
Solution Approach 1:
The light curtain's beam axes are divided into multiple selectable groups, where each group can be independently configured to trigger safety functions. This segmentation allows the system to differentiate between safety-critical and non-safety-critical beam interruptions, enabling selective shutdown behavior that maintains safety while avoiding unnecessary production stoppages.
Solution Approach 2:
Instead of triggering a complete system shutdown when any beam axis is interrupted, the system applies partial action by allowing interruptions in non-critical beam groups without triggering safety functions. This partial muting approach maintains safety for critical areas while permitting non-critical object passage, thereby preserving system availability.
2Productivity
If the entire light curtain is muted to allow non-safety-critical objects to pass, then system availability improves, but safety is reduced as the monitoring function is completely bypassed
Solution Approach 1:
The light curtain is segmented into multiple beam groups with different safety criticalities. Instead of muting the entire light curtain, only specific non-critical beam groups are muted, while critical beam groups remain active and capable of triggering safety functions. This selective muting approach preserves both safety and availability.
Solution Approach 2:
Different regions of the light curtain's monitoring area are assigned different safety qualities. Areas monitored by critical beam groups maintain full safety monitoring, while areas monitored by non-critical beam groups allow muted operation. This local differentiation enables simultaneous safety and availability in different spatial zones.
3Productivity
If partial muting is applied to specific beam axes, then system availability improves by allowing non-safety-critical objects to pass, but the complexity of configuring and managing beam groups increases
Solution Approach 1:
The safety controller is designed with multi-functional capabilities to automatically perform beam group identification, safety criticality assessment, and muting configuration. This universal functionality reduces the manual configuration burden despite the increased system capabilities, making the complex partial muting approach more manageable.
Solution Approach 2:
The system incorporates automatic beam group identification and configuration capabilities that reduce manual setup requirements. The safety controller can automatically analyze beam interruption patterns and configure appropriate muting strategies, enabling the system to partially configure itself and reduce overall configuration complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system minimizes unnecessary shutdowns by precisely adapting to non-safety-critical objects, maintaining system availability and safety by selectively muting beam axes during object passage.
Implementation Method 1
The light curtain features a series of transmitter-receiver pairs forming beam axes, by means of which a planar monitoring area is monitored
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The invention relates to a monitoring device (10) with a safety sensor in the form of a light curtain (1) and with a safety controller (14) which is connected to the light curtain (1) via a secure data connection (17). The light curtain (1) has a series arrangement of transmitter-receiver pairs forming beam axes (S1-S12), by means of which a monitoring area is monitored. The safety controller (14) includes a function block (18) and configuration means by which areas (B1, B2, B3) of the light curtain (1) are defined, each with a predetermined number of beam axes (S1-S12). These areas (B1, B2, B3) are supplied to the function block (18) as input signals. The light curtain (1) generates an output signal for each area (B1, B2, B3), and the output signals are read into the function block (18) via the secure data connection (17).The function block (18) generates a switching signal depending on the output signals.