MDM: A Mode Diagram Modeling Framework

TL;DR

This paper introduces a formal visual modeling framework called mode diagram for specifying and analyzing periodic control systems in safety-critical domains, incorporating property specification and statistical model checking.

Contribution

The paper presents a novel mode diagram framework with a property specification language and verification method tailored for periodic control systems in industry.

Findings

Successfully applied to real industry case studies

Detected two design defects in spacecraft control systems

Validated the effectiveness of the modeling framework

Abstract

Periodic control systems used in spacecrafts and automotives are usually period-driven and can be decomposed into different modes with each mode representing a system state observed from outside. Such systems may also involve intensive computing in their modes. Despite the fact that such control systems are widely used in the above-mentioned safety-critical embedded domains, there is lack of domain-specific formal modelling languages for such systems in the relevant industry. To address this problem, we propose a formal visual modeling framework called mode diagram as a concise and precise way to specify and analyze such systems. To capture the temporal properties of periodic control systems, we provide, along with mode diagram, a property specification language based on interval logic for the description of concrete temporal requirements the engineers are concerned with. The statistical model checking technique can then be used to verify the mode diagram models against desired properties. To demonstrate the viability of our approach, we have applied our modelling framework to some real life case studies from industry and helped detect two design defects for some spacecraft control systems.