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Questions tagged [system-identification]

Questions regarding techniques used to estimate unknown system parameters such as mass, friction coefficients, damping coefficients etc.

System identification is a domain which takes advantage of simple and advanced mathematical tools in order to estimate the values of unknown system parameters (mass, friction/damping coefficients, inertia coefficients etc) or even to produce a complete mathematical model of an arbitrary dynamic process. In order to do so, these techniques use collected input and output data of the physical system aimed to be identified.

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System identification of a simple motor with only position measurements

(Cross-posting from statistics stackexchange) Say we have a permanent-magnet DC motor that roughly obeys the system equation $$\ddot{x}(t) = \alpha \dot{x}(t) + \beta u(t) + \gamma $$ where $x(t)$ is the displacement of the rotor and $u(t)$ the…
user3716267
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Which rocket engines used this exotic cycle?

A "Hypergolic, Full Flow, and Closed Catalyst" cycle rocket engine Left side: All hydrazine goes through the centrifugal fuel pump All hydrazine undergoes thermal decomposition Out of it comes hot hydrogen gas and hot nitrogen gas All hot…
user50793
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Non-Linear grey box model Quadrotor system identification Matlab

I have been working with a commercial flight computer and have adjusted the gains of my controller. However, I want to perform a more in-depth analysis, which requires finding an appropriate model to fine-tune my gains. I have been experimenting…
David Nieto
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Using simple RNN to identify a simple dynamic linear system

I have been trying to identify a simple linear second order system (e.g. a pendulum or a mass-spring system), by simulating it in Python using backwards-euler method and then feeding the step changes in force as Input (x) to simple RNN network, and…
APasagic
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Measure a frequency response function

I have a slide here which says following: For the control loop ...apply $d$, measure $u$ and $y$, calculate $\hat{H}(f) = \frac{S_{yu}(f)}{S_{uu}(f)}$ but then typically $E\{\hat{H}(f)\} \ne H(f)$ Can someone explain to me the meaning of the last…
theNewOne
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