Control System Toolbox Release Notes |

Control System Toolbox 5.1 Release Notes

**New Features**

This section introduces the new features and enhancements added in the Control System Toolbox 5.1 since the Control System Toolbox 5.0 (Release 12.0).

For information about Control System Toolbox features that are incorporated from Version 5.0, see New Features in the Control System Toolbox 5.0 Release Notes.

**SISO Design Tool Enhancements**

Enhancements to the SISO Design Tool include the following:

- Save/load session -- You can now save the state of the SISO Design Tool before exiting and restore it at a later time.
- Graphical design constraints -- You can use a new set of design constraints that you move and shape with the mouse or specify by typing their parameter values. For example, the design constraints for root locus include damping ratios, settling time, natural frequency, and percent overshoot.
- Interactive open-loop Nichols plot -- You can use a new view to graphically tune the parameters of the feedback compensator. The open-loop Nichols plot contains the same functionality as the open-loop Bode diagram and root locus.
- Interactive Prefilter Design view -- You can now interactively shape the prefilter compensator. Both interactive graphics and a right-click menu are available.
- New compensator format -- You can display compensator transfer functions in the natural frequency format, which is of the form

- where
_{z1},_{z2}, ... and_{p1},_{p2}, ..., are the natural frequencies of the zeros and poles, respectively.

For detailed examples of how to use the SISO Design Tool, see Designing Compensators in *Getting Started with the Control System Toolbox*.

**Algorithmic Enhancements**

Enhancements to controls algorithms include

- M-circle grid for Nyquist plots
- A new function,
`bandwidth`

, that calculates the bandwidth of SISO systems - LTI models with complex data -- You can now specify transfer functions or state-space models with complex coefficients. Most commands work on such models,
*except*for the following: - New LTI method
`conj`

for use with LTI models with complex data (works for TF, ZPK, SS objects)

Platform Limitations for HP and IBM | Control System Toolbox 5.0 Release Notes |