SMT-Based Model Checking of Industrial Simulink Models

• Published in: Formal Methods and Software Engineering Vol. 13478; pp. 156 - 172
• Main Authors: Ishii, Daisuke, Tomita, Takashi, Aoki, Toshiaki, Ngo, The Quyen, Do, Thi Bich Ngoc, Takai, Hideaki
• Format: Book Chapter
• Language: English
• Published: Switzerland Springer International Publishing AG 2022; Springer International Publishing
• Series: Lecture Notes in Computer Science
• Subjects: MATLAB/Simulink; Model checking; SMT solvers
• ISBN: 9783031172434; 3031172434
• ISSN: 0302-9743; 1611-3349
• DOI: 10.1007/978-3-031-17244-1_10

The development of embedded systems requires formal analysis of models such as those described with MATLAB/Simulink. However, the increasing complexity of industrial models makes analysis difficult. This paper proposes a model checking method for Simulink models using SMT solvers. The proposed method aims at (1) automated, efficient and comprehensible verification of complex models, (2) numerically accurate analysis of models, and (3) demonstrating the analysis of Simulink models using an SMT solver (we use Z3). It first encodes a target model into a predicate logic formula in the domain of mathematical arithmetic and bit vectors. We explore how to encode various Simulink blocks exactly. Then, the method verifies a given invariance property using the k-induction-based algorithm that extracts a subsystem involving the target block and unrolls the execution paths incrementally. In the experiment, we applied the proposed method and other tools to a set of models and properties. Our method successfully verified most of the properties including those unverified with other tools.