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Loop-Shaping Design

Tune feedback loops for specified bandwidth and stability margins

At the command line, use looptune to tune SISO or MIMO feedback loops using a loop-shaping approach. looptune tunes a feedback loop to specified bandwidth and stability margins. In Control System Tuner, use Quick Loop Tuning for loop shaping of feedback loops.


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slTunerInterface for control system tuning of Simulink models
looptuneTune MIMO feedback loops in Simulink using slTuner interface
looptuneOptionsSet options for looptune
loopviewGraphically analyze results of control system tuning using slTuner interface
looptuneSetupConstruct tuning setup for looptune to tuning setup for systune using slTuner interface
looptuneTune fixed-structure feedback loops
looptuneOptionsSet options for looptune
loopview Graphically analyze MIMO feedback loops
looptuneSetupConvert tuning setup for looptune to tuning setup for systune
viewGoalView tuning goals; validate design against tuning goals
evalGoalEvaluate tuning goals for tuned control system


Loop-Shaping Basics

Set Up Your Control System for Tuning with looptune

To use looptune, create a parameterized representation of your controller and a numeric model of your plant.

Structure of Control System for Tuning With looptune

looptune tunes the feedback loop illustrated below to meet default requirements or requirements that you specify.

Tune MIMO Control System for Specified Bandwidth

Tune a fixed-structure MIMO control system to achieve a specified loop crossover frequency using looptune.

Tune Feedback Loops using looptune

The looptune command facilitates loop shaping design by automatically generating the tuning requirements.

How Tuned Simulink Blocks Are Parameterized

Both Control System Tuner and the slTuner interface automatically assign predefined parameterizations to certain Simulink® blocks.

Tune Control Systems in Simulink

At the command line, use systune or looptune to automatically tune control systems modeled in Simulink.

Building Tunable Models

Build a control-system model for tuning with systune or looptune using numeric LTI models for fixed elements and control design blocks for the tunable elements.

Mark Signals of Interest for Control System Analysis and Design

Analysis points allow you to access to internal signals, perform open-loop analysis, or specify requirements for controller tuning in systems modeled in either MATLAB® or Simulink.

Using Parallel Computing to Accelerate Tuning

Multiple optimization starts can improve control-system tuning results. If you have Parallel Computing Toolbox™, you can accelerate multi-start tuning strategies.

Loop-Shaping in Control System Tuner

Quick Loop Tuning of Feedback Loops in Control System Tuner

Tune a control system to meet specified bandwidth and stability margins in Control System Tuner, without explicitly creating tuning goals that capture these requirements.

Case Studies

Decoupling Controller for a Distillation Column

Use looptune to decouple the two main feedback loops in a distillation column.

Tuning of a Digital Motion Control System

Use looptune to tune a digital motion control system modeled in Simulink.

Multi-Loop PI Control of a Robotic Arm

This example shows how to use looptune to tune a multi-loop controller for a 6-DOF robotic arm manipulator.

Tuning of a Two-Loop Autopilot

Tune a two-loop autopilot controlling the pitch rate and vertical acceleration of an airframe.

Multi-Loop PI Control of a Robotic Arm

This example shows how to use looptune to tune a multi-loop controller for a 6-DOF robotic arm manipulator.