Dual Computer Bus Module for AS-i Safety Signal Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bus modules for safety-related signal output in AS-i bus systems require high fault tolerance and complex software development, leading to increased certification and approval efforts due to the need for error detection in computer units, which can be time-consuming and costly.
Innovation Solution
A bus module with two computer units that generate partial code sequences independently, ensuring a correct code sequence is only output if both units function properly, allowing for immediate detection of errors and reducing the required security category and certification complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single computer unit generates safety-related code sequences with high fault tolerance, then reliability is improved, but device complexity and certification effort increase
Solution Approach 1:
The code sequence generation is divided into two independent computer units, each generating only a portion of the code sequence. This segmentation reduces the complexity and certification burden for each individual unit while maintaining overall system reliability through the collaborative generation of the complete code sequence.
2Reliability
If error detection mechanisms are implemented in the computer unit, then reliability is improved, but development time and certification effort increase
Solution Approach 1:
Error detection is distributed across two computer units that independently generate portions of the code sequence. Each unit has simpler error detection requirements, reducing development time and certification effort compared to a single unit with comprehensive error detection.
Solution Approach 2:
The system uses feedback mechanisms where each computer unit monitors the other's output. If one unit produces an incorrect code portion, the other unit can detect the error through validation checks, ensuring reliability without requiring complex error detection in a single unit.
3Device complexity
If a single computer unit outputs safety-related code sequences, then device complexity is reduced, but reliability decreases due to potential undetected errors
Solution Approach 1:
The code sequence output function is segmented into two computer units that each generate a portion of the code. This segmentation increases reliability through distributed error detection while keeping the overall system structure relatively simple and maintaining compatibility with existing AS-i bus protocols.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed is a bus module that can be connected to a bus system (ASI) and comprises means (17, 27) for outputting safety-relevant signals in the form of repeated unambiguous code sequences (18). The inventive bus module further comprises a first and second arithmetic unit (10a, 10b; 20b, 20b) with means for executing software programs. A code generator program (11a, 21a) of the first arithmetic unit (10a, 20a) generates a first partial code sequence (12a) of the code sequence (18) while a code generator program (11b, 21b) of the second arithmetic unit (10b, 20b) generates the remaining portion of the code sequence (18) as a second partial code sequence (12b). Advantageously, a proper code sequence (18) is output at the output of the bus module only when both arithmetic units (10a, 10b; 20a, 20b) function properly. A deviation in the code sequence (18) that is output can then be detected by a monitor or actuator.