(Control Design & Simulation) State-Space block doesn't give output

I've tried and tried but can't get the State-Space block module to give me a graph / output.
I have no idea what the problem is and hope that somebody can help me. The numbers and calculations work in Matlab (Simulink) but i can't get it to simulate in labview.
Anybody got any ideas?
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Attachments:
Cavities.vi ‏30 KB
Matrixes.vi ‏27 KB

The problem is that you are assuming that LabVIEW executes left to right. Dataflow doesn't work this way. Your code as this:
does not tell LabVIEW that it has to execute everything from left to right. What is happening is that he is executing the 3 'island' of code in parallel and, in this case, it will have 'empty' values. You have to remove the local variables to make this work and dataflow paradigm will execute your code from left to right, as you want. here is the code:
Also, one more thing. Your input to the "CD Linear Simulation" is all zero. That means that you are trying to input zero input to a linear system, which will give you a zero output to the response. You probably do not want that since zero as input doesn't give you any more information. If you want to see how to system goes to zero after initial conditions, you should use "CD Initial Response". Or you should modify the input signal to the system. Please study this shipping example to understand how to use Linear Simulation and Initial Response:
C:\Program Files (x86)\National Instruments\LabVIEW 2012\examples\Control and Simulation\Control Design\Time Analysis\CDEx Time Domain Analysis.vi
Hope this helps...
Barp - Control and Simulation Group - LabVIEW R&D - National Instruments

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Solved!
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Attachments:
1.xls ‏7 KB
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Hi barp
Thanks for your reply, Erm for the second question, please take a look on the picture below. When the setpoint, desired speed is 500, the Actual Speed suppose osillating at 500 for instance (501, 502, 499), but in this case the actual speed is exactly 500, which is not the actual speed but is the desired speed.
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Jenő Kocsis wrote:
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I am trying to do a fairly simple state space task with Control Design and Simulation toolbox, however I am quite new at using this toolbox and need some help :-)
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Message Edited by SCMAJA on 10-16-2009 11:21 AM
LabVIEW 8.6 / 2009 / 2010
Vision Development Module 8.6 / 2009 / 2010
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Attachments:
2 DOF robot with ramp input, polar coordinates plot, state space.vi ‏49 KB

Hello Simon,
The error comes from your Ramp Input. Since your system is MIMO, you would need to feed in a vector input to the system.
I've changed your VI and attached here~!
Andy Chang
National Instruments
LabVIEW Control Design and Simulation
Attachments:
MIMO Robot VI.vi ‏76 KB

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Dear Chin ho,
After going through your questions I found some documentation which will be useful for you. But I you still have more questions, you can reply me any time.
1- About the data and amount of it I couldn't find any info but maybe you can use the new functions in LV version 2009 and find your answer.
Estimating States of Nonlinear Stochastic State-Space Models with Extended Kalman Filters
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The LabVIEW Control Design and Simulation Module provides tools to study the dynamics of systems described by linear time-invariant (LTI) continuous and discrete models. You can create deterministic state-space, transfer function, and zero-pole-gain models. You also can create stochastic state-space models and the second-order statistics noise models. You can use these forms to describe both single-input single-output (SISO) and multiple-input multiple-output (MIMO) systems.
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Continuous
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Discrete
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w is the process noise vector.
v is the measurement noise vector.
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B is an n × m input matrix of the given model.
C is an r × n output matrix of the given model.
D is an r × m direct transmission matrix of the given model.
n is the number of model states.
m is the number of model inputs.
r is the number of model outputs.
G is a matrix relating w to the model states.
H is a matrix relating w to the model outputs.
Q is the auto-covariance matrix of w.
R is the auto-covariance matrix of v.
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Solved!
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Hmm, thanks. It must've been the proxy server in the office. Disabled and it downloaded it via the wifi.
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Solved!
Go to Solution.
Attachments:
Project 1.png ‏12 KB
Project 2.png ‏18 KB

Well, my suggestion then is to do the following: change final time from Inf back to 10 s (or whatever number that capture the whole simulation) and do a while loop around the Control and Simulation Loop with a "wait until next ms" function to give you time to react and change parameters, like this below. This would make LabVIEW to do the whole simulation, wait for 1000 ms and then, run the simulation again with new parameters. If you need more time, just need to change the constant wired to the "wait until next milisecond".
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Hello
The problem is the following. The version of LabVIEW that you are using does not match the version of the evaluation version of LabVIEW Control Design and Simulation Module (CD&SIM). If that happens, the installer will not select the support files for your LabVIEW. If you download LabVIEW 2011, then you must install CD&SIM 2011.
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King regards
I love the smell of napalm in the morning

alij wrote:
its because the main labview is install in c:\program files , but when you install the module it will install in programfiles(x86) ,that because the **bleep**ing bug in the installation and programmers , plz fixx this , i think you have to copy paste files into the main NI labview which is in program files not program files (x86)...
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(Control Design & Simulation) State-Space block doesn't give output

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