Robust Control Toolbox
Design robust controllers for uncertain plants
Robust Control Toolbox™ provides functions and blocks for analyzing and tuning control systems for performance and robustness in the presence of plant uncertainty. You can create uncertain models by combining nominal dynamics with uncertain elements, such as uncertain parameters or unmodeled dynamics. You can analyze the impact of plant model uncertainty on control system performance and identify worst-case combinations of uncertain elements. H-infinity and mu-synthesis techniques let you design controllers that maximize robust stability and performance.
The toolbox adds robust tuning to the automated tuning capabilities of Control System Toolbox™. The tuned controllers can be decentralized with multiple tunable blocks spanning multiple feedback loops. You can optimize performance for the nominal plant while enforcing a lower, minimum performance over the entire range of uncertainty.
Build detailed uncertain models by combining nominal dynamics with uncertain elements, such as uncertain parameters or neglected dynamics. Represent uncertain systems using uncertain state-space and frequency response models.
Add uncertainty when linearizing Simulink models by designating some blocks as uncertain.
Robust Stability and Performance
Calculate the disk-based gain and phase margins of SISO and MIMO feedback loops. Quantify how uncertainty affects the stability and performance of your control system. Compute robust stability and robust performance margins for system-specific uncertainty.
Identify worst-case combinations of uncertain element values. Compute the worst-case values of tracking error, sensitivity, and disk margins. Compare nominal and worst-case scenarios.
Monte Carlo Analysis
Generate random samples of uncertain system within the specified uncertainty range. Visualize how uncertainty affects the system time and frequency responses. Use the Uncertain State Space block to inject uncertainty in Simulink and perform Monte Carlo simulations.
H-infinity and Mu Synthesis
Synthesize robust MIMO controllers using algorithms such as H-infinity and mu-synthesis.
Optimize H-infinity performance of fixed control structures. Automate loop-shaping tasks using the mixed-sensitivity or Glover-McFarlane approaches.
Robust Tuning of Uncertain Control Systems
Specify tuning requirements such as tracking performance, disturbance rejection, noise attenuation, closed-loop pole damping, and stability margins. Simultaneously tune for multiple plant models or control configurations. Maximize performance over the uncertainty range of plant parameters. Assess controller robustness in time and frequency response plots.
Reduce model order using additive or multiplicative error methods based on Hankel singular values of the system. Reduce the order of controllers produced by H-infinity and mu-synthesis algorithms to eliminate superfluous states while preserving the essential dynamics.
Synthesize discrete-time robust controllers using mu synthesis
Compute smallest destabilizing gain or phase perturbations
Visualize disk-based stability margins
Model gain and phase variations and enforce stability margins for robust controller design