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Questions tagged [system-identification]

Questions about "system identification" in the sense of control theory.

Questions about "system identification" in the sense of control theory. I.e. how to calibrate a model for the behaviour of a dynamic system.

See also https://en.wikipedia.org/wiki/System_identification

For questions on how to uniquely identify a client system, e.g. based on hardware serial numbers, the hardware-id tag shall be used.

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Discrete to continuous time transfer function

I implemented a class to identify ARX models in Python. The next step is the calculation of optimal PID parameters based on LQR. Apparently a continuous time model is required and I have the following possibilites: transform the discrete time model…
Yannick
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system identification using Least mean square algorithm

I am studying about system identification using Least Mean Square algorithm. I tried with some code using the equations for LMS. Based on the algorithm steps, the calculation of the error and weight updates looks alright. However, it fails to give…
remya
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Matlab: How to set the feedthrough characteristic in n4sid function for MIMO system identification?

I have a question regarding the feedthrough option in the n4sid function for subspace identification. According to the MathWorks help, 'Feedthrough' should be specified as a logical vector of length Nu, where Nu is the number of inputs. For example…
Mhatami
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How to evaluate sine-sweep (chirp) signal for system Identification

(for the quick reader) Question: Am I right that the Spectral analysis method to analyze a CHIRP is not so beneficial for parameter estimation/ model identification) [EDIT] My system is open-loop, 1 input (steering wheel angle) and 2 outputs…
Simon
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System Identification with nonuniform (irregular) sampled data

I am trying to identify the model of my quadcopter using MATLAB's System Identification toolbox (App) and the command line. I have both the input and output signals which are both non-uniformly sampled, specifically, the sample time between…
M.A.
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system identification for epidemic modelling in matlab

I am trying to estimate parameters using the system identification toolbox. I used the example of three ecological systems provided in the documentation, and worked on it o build my own model. Here is my model: > function [dx, y] = shigella(t, u,…
Ojaswita
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Creating a MATLAB system with tunable parameters for system identification

Im trying to get MATLAB to create a state space model with initial values, which i later have to fine tune using the system identification toolbox. The problem is that i am doing this with "white-box" models, which means that the A-matrix in my…
Rasmus Elbaek
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Understanding the compare command in Matlab

I am very puzzled by the following Matlab observation. In my problem I am trying to estimate an ARX/ARMAX model out of discrete sampled input-output data. I am following Matlab's guide to identify linear models in the command line (using the System…
titus.andronicus
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Identification of an ARX model with both linear equality constraints and stability

From input and output data I have to identify with least squares an ARX model y(n) = -a1 y(n-1) -....- aN y(n-N) + b1 x(n-1)+...+bM x(n-M) that has to be stable (all its poles are inside the unit circle) and at the same time the…
Simone Giorgi
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ARMAX fit Percent

I am using armax model to describe the relationship between two signals. I have used matlab armax function with different model orders. To evaluate the efficiency of the model I pulled the value from Report.Fit.FitPercent expecting that it will…
user3523143
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Using System Identification Toolbox transfer function with Simulink

I believe I am doing something fundamentally wrong when trying to import and test a transfer function in Simulink which was created within the System Identification Toolbox (SIT). To give a simple example of what I am doing. I have an input which is…
Jimog
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matlab command like arxstruct for systems like armax,oe,bj

arxstruct command help me to selects best ARX system order with a dataset data of input and output: NN = struc(1:5,1:5,1); and nn = selstruc(V,0); m = arx(z,nn); matlab selects best model order for an ARX system, but I don't find a way to do it…
cyberdyne
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matlab system identification toolbox gives me incorrect DC gain of transfer function

everyone. I'm trying to build a noise model using system identification toolbox. My system can be written as: y = C(z)/D(z) e . Basically I measure system response y purely due to unmeasured white noise e . I think system id will do the job since…
user37386
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Why does my non-linear regression system give poor validation results?

I am trying to identify a nonlinear system. This system is a differential drive AGV. Somehow the motion equations I found in a paper and the one from Simulinks Mobile Robotics Toolbox don't fit at all to my system. Hence I try to identify my system…
doublesobig
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Problem with System Identification of a Single-Tank Process using MATLAB and SIMULINK

I am an undergraduate currently working on a control design project that involves Nonlinear neural internal model control of a Quadruple Tank Process with Dead Times (QTPwDTs). I have been however stuck on performing system identification of a…
Similoluwa Okunowo
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