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LabVIEW Control Design Toolkit is freeware from Tech Teach.

The Control Design Toolkit was initially launched in Spring 2004. It expands LabVIEW's capabilities for control system and dynamic system analysis and design considerably. The set of functions available is comparable with the Control System Toolbox in Matlab and the similar control system function category in Octave.

Included in version 2.0 is the Control Design Assistant, which is an interactive tool which can be used independent of LabVIEW, and without LabVIEW programming (you can however create LabVIEW code from your Control Design Assistant project). The Control Design Assistant is available from the Start / Programs / National Instruments menu on your PC and from the Tools / Control Design Toolkit in LabVIEW.

The VIs in the examples does not contain any while loops. Consequently, the VIs run just once. If you want a VI to run continuously with a well-defined time step between each while loop execution, possibly while you are adjusting some parameters, you can place the block diagram code in while loop.

Here are its Contents:

1 Preface
2 The contents of the Control Design Palette
3 Creating models
3.1 Creating continuous-time (s-)transfer functions
3.2 Creating discrete-time (z-)transfer functions
3.3 Creating continuous-time state-space models
3.4 Creating discrete-time state-space models
3.5 Standard transfer functions
3.6 PID controllers
3.7 Writing models to file. Reading models from file
3.8 Getting information about a model
3.9 Converting Control Design models to/from Simulation Module models
4 Connecting models
4.1 Series connection
4.2 Feedback connection
5 Calculating transfer functions from state-space models
6 Discretizing continuous-time models
7 Simulation (time responses)
8 Frequency response
9 An application: Control system analysis and simulation

An application: Analysis and simulation of control system

Example 9.1: Control system analysis and simulation

The VI shown below shows how to analyze and simulate a feedback control system. The block diagram code is put inside a while loop with cycle time 100ms to make the program run continuously. The controller is a PID Academic controller (which has parallel form) with the following transfer function, Hc(s):



A Pade approximation is used to represent the time delay of the process because the CD Feedback function works correctly only if there are only rational transfer functions in the feedback loop.




Front panel and block diagram of controlsys_analysis.vi.