Requirements-Aided Automatic Test Case Generation for Industrial Cyber-physical Systems

Abstract

Industrial cyber-physical systems require complex distributed software to orchestrate many heterogeneous mechatronic components and control multiple physical processes. Industrial automation software is typically developed in a model-driven fashion where abstractions of physical processes called plant models are co-developed and iteratively refined along with the control code. Testing such multi-dimensional systems is extremely difficult because often models might not be accurate, do not correspond accurately with subsequent refinements, and the software must eventually be tested on the real plant, especially in safety-critical systems like nuclear plants. This paper proposes a framework wherein high-level functional requirements are used to automatically generate test cases for designs at all abstraction levels in the modeldriven engineering process. Requirements are initially specified in natural language and then analyzed and specified using a formalized ontology. The requirements ontology is then refined along with controller and plant models during design and development stages such that test cases can be generated automatically at any stage. A representative industrial water process system case study illustrates the strengths of the proposed formalism. The requirements meta-model proposed by the CESAR European project is used for requirements engineering while IEC 61131-3 and model-driven concepts are used in the design and development phases. A tool resulting from the proposed framework called REBATE (Requirements Based Automatic Testing Engine) is used to generate and execute test cases for increasingly concrete controller and plant models.

A Survey of Static Formal Methods for Building Dependable Industrial Automation Systems

“…It proposes a formal semantics for a significant fragment of the instruction list language, and a direct mapping of the semantics into a model checking tool. A requirements-based test-generation and tracking simulation based execution technique for systems built using IEC 61131-3 appears in [74]. Some works, such as [75], target test-case generation for complete systems.…”

Survey on test case generation, selection and prioritization for cyber‐physical systems

“…Sinha et al [93] (2015): Problem: Sinha et al [93] argue that testing CPSs, which are typically developed in a model-driven fashion as multidimensional systems, is extremely difficult because models are often not accurate and do not correspond accurately to subsequent refinements and because the software must eventually be tested on the real system, especially where safetycritical systems such as nuclear plants are concerned [93]. Approach: The authors propose an approach for CPSs that generates test cases based on high-level functional requirements, for every phase of the design cycle and at all test levels in the model-driven engineering process, by combining V-Model and model-driven engineering.…”

A Systematic Literature Review on Model-driven Engineering for Cyber-Physical Systems

“…Results of this correlation are presented in Table 19. Applications included in these studies take into account Industry 4.0/Cyber-physical production systems (CPPS) [89,18,17,35,20,67,141,81], Industrial Applications [146,134,125], Automation Systems [23,157], evolvable production systems [30,29], and Assembly systems (ASs) [140].…”

“…Case study IKEA Gregor office chair [140], assembly production system [30], assembly system [29], Petroamazonas EP Oil Company [67], liqueur plant [141], industrial water process system [134], enterprise production line [81] Empirical study…”