The continuous time biquad state space structure

State space models of highly flexible systems can present severe numerical issues. The models derived from physical principles often lack structure. Canonical form models, are compact, but obscure any physical structure and can have coefficients that are highly sensitive to model parameters. In [1] we discussed discrete state space structure that allowed for minimal latency estimation and control while preserving the numerical properties of biquad filters. In this paper, we discuss a continuous time version, suitable for modeling from physical principles.