Stateflow

Stateflow (developed by MathWorks) is a control logic tool used to model reactive systems via state machines and flow charts within a Simulink model. Stateflow uses a variant of the finite-state machine notation established by David Harel, enabling the representation of hierarchy, parallelism and history within a state chart.<ref>MATLAB Tech Talks on the basics and usage of state machines</ref><ref>Simulation of Hybrid Systems Using Stateflow</ref> Stateflow also provides state transition tables and truth tables.

Common uses

Stateflow is generally used to specify the discrete controller in the model of a hybrid system where the continuous dynamics (i.e., the behavior of the plant and environment) are specified using Simulink.<ref>Template:Cite journal</ref><ref>Orion GN&C MATLAB/Simulink/Stateflow Standards</ref>

Specific applications for Stateflow include:

• Mode logic, where each discrete mode of a system is represented by a state<ref>Template:Cite journal</ref>
• Fault management, where the Stateflow chart is used to control how the system responds to faults and failures within a system<ref>Requirements-Based Testing in Aircraft Control Design</ref>
• Task scheduling, where the Stateflow chart is used to schedule when specific tasks occur, either within the Stateflow chart or within the overall Simulink model<ref>Embedded Coder Robot NXT Modeling Tips</ref>

Extensions

A number of MathWorks and third-party tools can be used with Stateflow to validate the design and generate code. For example, Simulink Verification and Validation, a MathWorks tool, can be used to check for requirements traceability and model coverage analysis. Other add-on code generation tools can be used to automatically generate C, C++, HDL, and PLC code for implementation on embedded systems.