Optical Muting Sensor Classification to Avoid Unnecessary Safety Stops

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing safety devices struggle to reliably distinguish between safety-critical and non-safety critical objects, leading to unnecessary system shutdowns when non-critical objects are present.

Innovation Solution

The safety device incorporates an optical muting sensor with an image sensor that captures a moving object in at least two different positions, analyzing patterns to determine if the object is permissible, thus allowing the safety sensor to operate in a muting mode and avoid unnecessary system shutdowns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the safety sensor triggers the safety function when detecting any object in the monitoring area, then the safety level is improved, but the system availability deteriorates due to unnecessary shutdowns when non-safety-critical objects pass through

Engineering Contradiction:
Improvesafety levelVSAvoidsystem availability
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies local quality by differentiating the treatment of objects in the monitoring area. Instead of uniformly triggering the safety function for all objects, the system evaluates object characteristics (size, shape, movement pattern) to determine whether to activate the safety function or enter muting mode. This selective approach maintains high safety levels for critical objects while preventing unnecessary shutdowns for non-critical objects like transport vehicles.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent utilizes parameter changes by analyzing multiple object parameters (dimensions, movement characteristics, position) to dynamically adjust the safety sensor's response. The evaluation electronics compare detected object parameters against predefined criteria to decide between triggering the safety function or activating muting mode, thereby optimizing both safety and availability based on real-time object characteristics.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the safety sensor operates in muting mode to allow non-safety-critical objects to pass through, then the system availability is improved, but the safety level deteriorates if safety-critical objects are not properly distinguished

Engineering Contradiction:
Improvesystem availabilityVSAvoidsafety level
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by evaluating object characteristics before the safety sensor triggers or mutes. The evaluation electronics analyze object parameters (size, shape, movement pattern) in advance to determine the appropriate mode. This preliminary evaluation ensures that safety-critical objects are identified and processed appropriately before any safety function activation or muting occurs, maintaining safety levels while enabling availability improvements.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback by continuously monitoring object detection results and adjusting the safety sensor's operational mode accordingly. The evaluation electronics provide feedback signals based on object analysis, dynamically switching between safety function activation and muting mode. This closed-loop feedback mechanism ensures that safety levels are maintained while maximizing system availability through intelligent mode selection.

Inventive Principle:
Principle #23Feedback

3Device complexity

If traditional muting sensors are used to detect permissible objects, then the device complexity is reduced, but the object classification reliability deteriorates due to inability to reliably distinguish between safety-critical and non-safety-critical objects

Engineering Contradiction:
Improvesensor system complexityVSAvoidobject classification accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent applies universality by making the safety sensor itself perform multiple functions: both safety monitoring and object classification for muting decisions. The evaluation electronics of the safety sensor are enhanced to analyze object characteristics and determine whether to activate safety functions or enter muting mode. This multi-functional approach eliminates the need for separate muting sensors while improving object classification accuracy through comprehensive object parameter analysis.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the safety sensor and muting sensor functions into a single integrated system. The safety sensor's evaluation electronics are enhanced to perform both safety-critical object detection and non-critical object identification for muting purposes. This consolidation reduces device complexity by eliminating separate muting sensors while improving classification reliability through unified, comprehensive object analysis.

Inventive Principle:
Principle #5Merging (Combining)

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

This solution enhances the reliability and availability of the safety device by accurately identifying permissible objects and preventing unnecessary system shutdowns, while maintaining a high level of safety.

Implementation Method 1

The muting sensor is an optical sensor which has an image sensor as a receiver unit, wherein a moving object is detected in at least two different positions with the optical sensor

Methodology Applied
Scientific EffectLight reflection: Reflection

Data Source

PatentEP4538580A1Safety device and method for operating a safety device
Publication Date: 2025.04.16 LEUZE ELECTRONIC GMBH & CO KG
  • EP4538580A1 patent drawingFigure 1
  • EP4538580A1 patent drawingFigure 2
  • EP4538580A1 patent drawingFigure 3~4

AI summary

The invention relates to a safety device (1) comprising a safety sensor (4) and a muting sensor (7), wherein the safety sensor (4) is configured to monitor a monitoring area. The safety sensor (4) is configured to trigger a safety function when it detects an object tampering with the monitoring area. The muting sensor (7) is configured to detect a permissible object, and the safety device (1) overrides the safety function when a permissible object is detected by the muting sensor (7). The muting sensor (7) is an optical sensor which includes an image sensor (13) as a receiver unit, wherein the optical sensor detects a moving object in at least two different positions. Based on the patterns detected by the image sensor (13), it is determined whether the object is a permissible object or not.