Towards Multi-View Test Specification in CPPS Engineering

Abstract

In context of Industry 4.0, the engineering of Cyber-Physical Production Systems (CPPSs) need to incorporate a heterogeneous set of engineering disciplines, data models, and artefacts. The quality of related data models and engineering artefacts is success-critical for the engineering process and the planned CPPS. Software and System tests aim at improving the quality of a CPPS. However, in CPPS, risk cases are often unknown and insufficiently covered by systematic testing methods, especially in heterogeneous environments. In this paper, we describe a multi-view test specification (MVTS) approach based on a risk analysis to systematically derive regular and negative/error test cases in CPPS engineering. We build on the PPR Asset Network (PAN) that provides the structure of a CPPS from product, process, resource perspective and their dependencies, and the Failure Mode and Effect Analysis (FMEA) to efficiently identify risks in CPPS engineering. We conceptually evaluate the MVTS approach with domain experts in a feasibility study to show benefits and limitations in context of traditional software testing. First results showed benefits of the MVTS approach with the help of the PAN and FMEA to systematically capture risks and derive test cases. While the execution of test cases is often limited to the regular systems behavior, negative test are often not executed because of possible physical damages. However, negative test cases can raise the awareness of possible critical risks during CPPS planning and design.