Using Simulink

System Functions

Each Simulink block type is associated with a set of system functions that specify the time-dependent relationships among its inputs, states, and outputs. The system functions include

• An output function, f_o, that relates the system's outputs to its inputs, states, and time
• An update function, f_u, that relates the future values of the system's discrete states to the current time, inputs, and states
• A derivative function, f_d, that relates the derivatives of the system's continuous states to time and the present values of the block's states and inputs

Symbolically, the system functions can be expressed as follows

where t is the current time, x is the block's states, u is the block's inputs, y is the block's outputs, x_d is the block's discrete derivatives, and x'_c is the derivatives of the block's continuous states. During a simulation, Simulink invokes the system functions to compute the values of the system's states and outputs.

States

Block Parameters