Converting linear state space into a transfer function

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SUMMARY

The discussion centers on the process of converting a linear state space representation into a transfer function, specifically addressing the use of the Laplace transform in this context. The transfer function is derived using the formula \( C \cdot [SI - A]^{-1} \cdot B \), where the matrix operations yield a transfer function of \(-0.5/s^2 + s + 0.5\). Participants clarify that while Laplace transforms are not explicitly required for the conversion, they are essential for analyzing system stability and feedback gain. The conversation highlights the algebraic manipulation of polynomials in the s-domain as a critical step in determining system characteristics.

PREREQUISITES
  • Understanding of linear state space representation
  • Familiarity with transfer functions and their derivation
  • Knowledge of Laplace transforms and their applications
  • Basic algebra involving polynomials in the s-domain
NEXT STEPS
  • Study the derivation of transfer functions from state space models
  • Learn about the application of Laplace transforms in control systems
  • Research methods for analyzing system stability using pole placement
  • Explore feedback gain calculations in linear control systems
USEFUL FOR

Control engineers, systems analysts, and students studying linear control theory will benefit from this discussion, particularly those focused on state space representations and transfer function analysis.

Std
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Homework Statement
Need elaboration in solving steps of...

Given The state space X(k)= [ 0.5 -0.5; 0.5 0.5] X(k-1) + [0;1] u(k) and out y(k) = [ 1 0] x(k) It is requested to get the tansfer function, Stability... and to design state feedback gain [k1 k2] to place the system poles at the origin....
Relevant Equations
transfer function is = C* [SI-A]-1 * B
My questions are now... Do the steps of converting this space to transfer function include any laplace ? or just we do get [SI-A]-1 and then transfer function is = C* [SI-A]-1 * B As [1 0] * [s-1/det -0.5/det ; 0.5/det s-0.5/det] * [0; 1] = -0.5/s^2+s+0.5 I mean do we need any laplace after that and if yes ?? Why and when shall we use it?? Also what is the difference in steps of solving if the question given was descriping the state as x' not x(k)?

How to get stability ... and feedback gain??
 
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I see this is a couple of months old. Where have these questions been? It also appears that @Std has been inactive since right after posting.

It has been awhile for me, so I'd have to look it up to get the steps to solve it. As I remember it, you should be able to stay in the s-domain solving for the poles and the gain, though. It's mostly algebra with the polynomials in s, if I remember correctly.
 

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