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Linear System

Definition

x˙(t)=Ax(t)+Bu(t)+cy(t)=Cx(t)+Du(t)+k\begin{align*} \dot{x}(t)=Ax(t)+Bu(t)+c \\ y(t)=Cx(t)+Du(t)+k \end{align*}

where x(t)Rnx(t) \in \mathbb{R}^{n} is the system state, u(t)Rmu(t) \in \mathbb{R}^{m} is the system input, y(t)Rpy(t) \in \mathbb{R}^{p} is the system output, and ARn×nA \in \mathbb{R}^{n \times n}, BRnB \in \mathbb{R}^{n}, cRnc \in \mathbb{R}^{n}, CRp×nC \in \mathbb{R}^{p \times n}, DRp×mD \in \mathbb{R}^{p \times m}, kRpk \in \mathbb{R}^{p}.

Example

[x0˙x1˙]=[2013][x0x1]+[11]uy=[1 0][x0x1]\begin{align*} \begin{bmatrix} \dot{x_{0}} \\ \dot{x_{1}} \end{bmatrix} &= \begin{bmatrix} -2 & 0 \\ 1 & -3 \end{bmatrix} \begin{bmatrix} x_{0} \\ x_{1} \end{bmatrix} + \begin{bmatrix} 1 \\ 1 \end{bmatrix} u \\ y &= \begin{bmatrix} 1 \ 0 \end{bmatrix} \begin{bmatrix} x_{0} \\ x_{1} \end{bmatrix} \end{align*}