Efficient Test Case Generation from Product and Process Model Properties and Preconditions

In Cyber-Physical Production System (CPPS) engineering for discrete manufacturing, the definition of test cases is vital to ensure correct behavior of production processes and to test risky cases. Unfortunately, the definition of test cases requires know-how both from the CPPS engineering domain and on software test automation, and is time-consuming. In this paper, we investigate how domain experts can efficiently derive test cases for an assembly process step from process preconditions concerning product properties. We introduce the Test Case Derivation for PPR Models (TCD4PPR) method building on the Formalised Process Description and best practices from software testing. We evaluate the TCD4PPR method with an illustrative use case from industry in a feasibility study with domain experts at a large production systems engineering company for discrete manufacturing. The main result was that the domain experts found the TCD4PPR method efficient, usable, and useful. The evaluation results indicate that investing reasonable effort into modeling Product, Process, Resource (PPR) knowledge with preconditions can considerably reduce risks of untested production process behavior.