Search for:
Mechatronic paths with missing safety mechanisms
Explanation:
Error detections and error responses will be searched for which are part of incomplete mechatronic paths, as well as detection and prevention actions, of which no safety mechanism have been derived yet.
A mechatronic path is incomplete when an error detection occurs without an error response – and vice versa.
Example:
Abbreviations:
- The example to demonstrate the way the described Quality Rule (QR) works has the structure shown above which also contains those IQ objects to be found by the described QR. These include altogether six preventive and detection actions as well as three error detections and error responses.
- From the following failure graph, you can see how the individual failures are linked to each other and how the safety mechanisms (error detections, error responses) are embedded within the failure net.
- Using the MSR form (see next figure) and the note symbols contained, you can see that both (planned) actions DA(6) and PA(6) are not yet linked to a safety mechanism. The reason for that is that no safety mechanisms have been derived yet derived from these actions.
Applying the discussed QR in the MSR form under the above circumstances produces the following search result:
Search result: 
Because the visual analysis of the failure graph (see above) shows that on the one hand the error detections Er Det 2 and Er Det 3 have no link to an error response and because on the other hand the error response Er Resp 2 has no link to an error detection, Er Det 2, Er Det 3, and Er Resp 2 are marked as hits. Since the two note symbols for the two actions DA(6) and PA(6) in the MSR form indicate that no safety mechanisms have yet been derived from these actions, DA(6) and PA(6) are also shown as valid QR search hits.
The safety mechanism Er Resp 3 anchored at the error response is not part of the search result, because it is unlinked and not shown in the MSR form.