Converting a simple mass-spring system to state-space model, how?

AI Thread Summary
The discussion focuses on converting a simple mass-spring system represented by the equation m*x" + k*x = f(t) into a state-space model. The parameters given are m = 5 and k = 1, leading to the identification of two state variables: x1 = y and x2 = y'. The participant attempts to establish the state-space matrices, proposing A, B, C, and D matrices but realizes a correction is needed for the A matrix. The final A matrix should reflect the correct dynamics, specifically A = [0 1; -k/m 0], which simplifies to A = [0 1; -1/5 0]. The discussion highlights the importance of understanding state-space representation in control systems.
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Homework Statement



Hi guys/girls

Professor gave this very simple homework where I need to convert the system below to a state-space model.
Mass_spring.png

The system itself is represented by the equation
Code:
m*x" + k*x = f(t)
Where m = 5 and k = 1. Note that, " (doublequote) is a second-order derivative.
Unfortunately I don't have the background to solve it because I slacked too much :redface:

Homework Equations


State-space model that we use is below:
ddfd74546a0e35f9ec054af2ecd3f2fa.png

d0ac09f5cde2ce822ecc3e369692d04b.png


Any help&explanation would be appreciated, thank you.

EDIT: Ok, I've just read the rules and apparently I'm not allowed to as for solutions without an attempt to solve it. Since I can't even attempt, may I ask a good place/source to start?
 
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attempt:

Code:
5y" + 0y' + y = u

since my diff. eq. is second order, I should have 2 state variables:
Code:
x1 = y
x2 = y'
so the state space model's matrixes become
Code:
A = [ 0 1 ]   B = [ 0 ]
    [ 1 0 ]       [ 1 ]

C = [ 1 0 ]   D = [ 0 ]

does it look ok?
 
Dude,

A = [0 1]
[(-k/m 0]

-k/m = -1/5 lol!
 
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