Finite State Machine

Finite state machines for modeling control logic

A finite state machine is a model of a reactive system. The model defines a finite set of states and behaviors and how the system transitions from one state to another when certain conditions are true.

Finite state machines are used to model complex logic in dynamic systems, from automatic transmissions to robotic systems to mobile phones. Examples of this complex logic include:

• Scheduling a sequence of tasks or steps for a system
• Defining fault detection, isolation, and recovery logic
• Supervising how to switch between different modes of operation

You can model finite state machines with Stateflow software and integrate them into a Simulink model. These finite state machines are represented by state charts, which provide additional capabilities beyond traditional finite state machines, including:

• Modeling hierarchical states for large-scale systems
• Adding flow graphs to define complex decision logic
• Defining orthognal states to represent systems with parallelism

General Introduction

• Stateflow Overview 1:58 (Video)
• Introduction to Stateflow for Controls Applications 22:01 (Video)
• Modeling Logic in Communications Applications (Part 1) 8:20 (Video)
• Finite State Machine Concepts (Documentation)

Aerospace and Defense Applications

• Fault Detection for an Aircraft Control System (Example)
• Develop Logic for a Launch Abort System 12:46 (Video)
• Spacecraft Automated Landing System 17:56 (Video)
• Requirements-Based Testing in Aircraft Control Design (AIAA Paper)

Automotive Applications

• Modeling a Fault-Tolerant Fuel Control Systems (Example)
• Automotive Powertrain Control System 17:21 (Video)
• Automatic Transmission Control (Example)
• Hybrid Electric Vehicle Modeling and Simulation (Webinar)

See also: control logic, state diagram, control systems, embedded systems, state-chart