Finite State Machine (FSM) Use Cases

Finite State Machines (FSMs) are powerful tools for modeling various systems and processes. Below is a categorized list of use cases along with their descriptions.

Control Systems

FSMs are commonly used in systems that require controlled sequences of operations.

Examples:

• Elevator Control: States for each floor, with transitions based on button presses.
• Traffic Light Control: States for “Red”, “Green”, “Yellow” with timed transitions.
• HVAC Systems: States like “Cooling”, “Heating”, “Idle” based on temperature input.

User Interfaces and Interaction

FSMs effectively model user interactions and navigation within applications.

Examples:

• UI Navigation: States for different screens (e.g., “Home”, “Settings”, “Profile”).
• Button Debouncing: States for “Pressed”, “Released”, “Bouncing”.
• Modal Dialogs: States for “Open”, “Closed”, “Minimized”.

Communication Protocols

FSMs define how systems exchange messages or data.

Examples:

• Network Protocols: States like “Listening”, “Connected”, “Data Transfer”.
• HTTP Requests: States for “Idle”, “Sending”, “Receiving”, “Completed”.
• Bluetooth Pairing: States like “Discoverable”, “Paired”, “Connected”.

Games and AI Behavior

FSMs model game mechanics and non-player character (NPC) behaviors.

Examples:

• Game Mechanics: States for “Playing”, “Paused”, “Game Over”.
• NPC Behavior: States for “Idle”, “Patrolling”, “Chasing”, “Attacking”.
• Turn-Based Games: States for “Player Turn”, “Enemy Turn”, “Victory”, “Defeat”.

Workflow and Process Management

FSMs are ideal for orchestrating complex process flows.

Examples:

• Business Workflows: States for “Draft”, “Submitted”, “Approved”, “Rejected”.
• Manufacturing Processes: States for “Idle”, “Processing”, “Completed”.
• E-Commerce: Order states like “Pending”, “Shipped”, “Delivered”.

Object Lifecycles

FSMs track the lifecycle of objects over time.

Examples:

• Document States: “Draft”, “Reviewed”, “Published”, “Archived”.
• User Accounts: “Created”, “Verified”, “Suspended”, “Deleted”.
• Vehicles: “Parked”, “Moving”, “Stopped”, “Broken Down”.

Software Systems

FSMs are widely used in software development for state management and feature implementation.

Examples:

• State Management: In front-end frameworks (e.g., Redux FSMs).
• Parsing Algorithms: States for “Start”, “Reading”, “Error”, “End”.
• Middleware: States for “Initializing”, “Processing”, “Error Handling”.

Robotics and Automation

FSMs model decision-making and task execution in robotics.

Examples:

• Robot Motion: States for “Idle”, “Moving”, “Charging”.
• Assembly Line Control: States for “Loading”, “Processing”, “Unloading”.
• Autonomous Vehicles: States for “Stopped”, “Moving”, “Avoiding Obstacle”.

Security Systems

FSMs model authentication and access control.

Examples:

• Authentication: States for “Logged Out”, “Logging In”, “Logged In”.
• Alarm Systems: States like “Armed”, “Disarmed”, “Triggered”.
• Access Gates: States for “Locked”, “Unlocked”, “In Use”.

Data Processing and Analysis

FSMs assist in pattern recognition and data validation.

Examples:

• Regex Engines: States for “Matching”, “Failed”, “Completed”.
• Stream Processing: States for “Reading”, “Buffering”, “Flushing”.
• Tokenizers: States for “Start”, “In Token”, “End of Token”.

Embedded Systems

FSMs control hardware components in embedded systems.

Examples:

• Microcontroller Programs: States for “Waiting”, “Processing”, “Sleeping”.
• Printers: States like “Idle”, “Printing”, “Error”.
• Consumer Electronics: States for “On”, “Off”, “Standby”.

Educational Tools

FSMs model and teach conceptual systems.

Examples:

• Language Learning: States for different grammar rules or word formations.
• Educational Games: States for levels or challenges.
• Quiz Systems: States for “Question”, “Answer”, “Feedback”.