2nd ICAI 2022

International Conference on Automotive Industry 2022

Mladá Boleslav, Czech Republic

can be generated directly in the failure net via the context menu. The purpose of the mechatronics FMEA is to be able to revaluate causations after they entered different operating conditions by means of error detections and error reactions and therefore lead to other or differently weighted effects.

3. Problem Solution

3.1 Required steps in safety measures analysis In the following text we will show how the fulfilment of safety goals for a system with electric parking brake (EPB) [6]. We can show using a suitable system FMEA (S-FMEA) model for verification safety goals. To create S-FMEA model we used APIS IQ [7] as a world-wide acceptable software tool. In creation of verification FMEA model we will follow steps: 1. Structural analysis for vehicle system with EPB. At Figure 1 we can see a structure of EPB system. Failure effects (it is a FMEA term) are defined on Vehicle level, failure modes are located on brake assembly level and failure causes on components level leads to the failure modes on Brake Assembly level 2. Functional analysis and functional net for vehicle with EPB is followed after creation of structural analysis. Functions at Vehicle level represents all safety goals derived from hazard analysis and risk assessment (HARA). A set of functions at Brake Assembly level represents implemented functions in EPB. Functions at Component level represent implemented subfunctions in EPB components (we created them from VDA-305-100 standard [5] 3. Failure Analysis and failure net. Failures at vehicle level represents violations of safety goals. Failures at Brake Assembly level represents its failure modes. Failures at Components levels generate causes of failures at Brake Assembly and at the end violation of safety goals at Vehicle level. At Figure 2 is possible to see an example from APIS IQ software screen and explanation how failure causes generate failure effects on vehicle level which exact mean violation of safety goals. 4. Safety measures analysis with APIS IQ software. Safety measures analysis we performed by APIS IQFMEA editor with its “Mechatronics FMEA” extension [7]. At Figure 3 to Figure 5 reader can see installed safety measures in system FMEA (see next chapter). 3.2 Description of safety measures and mechanism in S-FMEA built on APIS IQ software 3.2.1 Error detection functions and error detection The creation of safety measures in the S-FMEA model in the APIS IQ environment requires a specific procedure, which we will describe in the following text. The Figure 3 represents a screenshot from APIS-IQ and describes error detection mechanism which was added to S-FMEA. On left upper part of figure (APIS IQ structure editor), for Brake Assembly two structures (elements) can be seen: at level 2 “2_Failure reactions”

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