Dual-Controller Circuit Verification Using Challenge-Response Checks

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current safety-critical automation tasks require dedicated and expensive hardware, limiting their implementation on standard industry hardware and complicating continuous monitoring and control without interrupting the process.

Innovation Solution

A circuit arrangement using two electronic computing devices with internal and external data sensors, employing a challenge-response mechanism for authentication and functional checks, allowing safe operation on standard industry hardware without dedicated fail-safe PLCs, enabling seamless upgrades and secure system reactions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If dedicated fail-safe PLC hardware is used for safety-critical automation tasks, then system reliability is improved, but hardware cost and complexity increase

Engineering Contradiction:

Improvesystem reliabilityVSAvoidhardware complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent creates a virtual copy of the safety-critical control function by implementing it as software on standard hardware. Instead of using dedicated fail-safe PLC hardware, the control function is copied and executed on commercially available standard hardware platforms, thereby reducing hardware complexity and cost while maintaining reliability through software-based safety mechanisms

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent replaces the mechanical/electrical dedicated hardware system (fail-safe PLC) with a software-based control system running on standard hardware. This substitution eliminates the need for specialized hardware while achieving the same safety-critical functions through software implementation and virtualization

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If dedicated fail-safe PLC hardware is used, then safety functionality is ensured, but cost increases

Engineering Contradiction:

Improvesafety functionalityVSAvoidcost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent employs commercially available standard hardware that is inexpensive and readily replaceable, substituting expensive dedicated fail-safe PLC hardware. The standard hardware can be easily manufactured and deployed at lower cost, while the software-based safety mechanisms ensure continued safety functionality

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent makes standard hardware capable of performing safety-critical functions through software implementation. The same standard hardware platform can serve multiple purposes including both safety-critical control and general automation tasks, thereby reducing overall system cost while maintaining safety functionality

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Ease of manufacture

If standard industry hardware is used, then cost is reduced, but reliability for safety-critical tasks deteriorates

Engineering Contradiction:

ImprovecostVSAvoidreliability for safety-critical tasks

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent introduces a software layer as an intermediary between the standard hardware and the safety-critical control functions. This software intermediary ensures that reliability requirements are met by implementing safety mechanisms, monitoring, and control logic that guarantee safe operation even when using cost-reduced standard hardware

Inventive Principle:

Principle #24Intermediary (Mediator)

4Reliability

If homogeneous redundant components are used on two electronic computing devices, then reliability is improved, but development costs increase

Engineering Contradiction:

ImprovereliabilityVSAvoiddevelopment costs

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent uses identical or homogeneous electronic computing devices for redundant deployment. Both computing devices run the same safety-critical control software and can interchangeably perform the safety functions, simplifying development and maintenance while ensuring reliability through redundancy

Inventive Principle:

Principle #33Homogeneity

Data Source

PatentEP4502739A1Method for testing the functionality of a circuit for a control of a machine by means of the circuit, computer program product, computer-readable storage medium and circuit

Publication Date: 2025.02.05 SIEMENS AG

Figure 1
Figure 2

AI summary

The invention relates to a method for verifying the functionality of a circuit arrangement (16) for controlling a machine (12), comprising the steps of: providing a first electronic computing device (18) for generating a first control signal (20) for the machine (12), wherein the first electronic computing device (18) has at least a first internal and a second external data sensor (22, 40); providing a second electronic computing device (28) for generating a second control signal (30) for the machine (12), wherein the second electronic computing device (28) has at least a second internal and a first external data sensor (32, 38); generating a second request-response method (54) for the first electronic computing device (18) and/or a first request-response method (56) for the second electronic computing device (18);Evaluating the second request-response procedure (54) and/or evaluating the first request-response procedure (56); and verifying the functionality depending on the evaluation. Furthermore, the invention relates to a computer program product, a computer-readable storage medium, and a circuit arrangement (16).