Kalman-Bucy Filter: Calculate Eqns

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The discussion centers on calculating the Kalman-Bucy Filter equations, specifically focusing on the derivation of the covariance matrices Q and R. Participants clarify that Q represents the process noise covariance while R denotes the measurement noise covariance, both of which are critical for the filter's performance. There is uncertainty about how to derive these matrices from the given F matrix and output data. It is noted that while the Kalman filter can function without Q, R is essential. Additionally, concerns are raised about the formulation of the problem, particularly regarding the state transition matrix F needing to be square.
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Homework Statement



Calculate the Kalman-Bucy Filter equations

Homework Equations


F=(0 1)'
K is unknown but y = X_1 + d/dt(v)
E=((Fw-Kv)(Fw-Kv)')=FQF' + KRK'
Q = E(ww') and R = E(vv')

The Attempt at a Solution


There is more to this question but I am just having trouble understanding where Q and R come from if w is q and v is 1.
 
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dmorris619 said:

Homework Statement



Calculate the Kalman-Bucy Filter equations

Homework Equations


F=(0 1)'
K is unknown but y = X_1 + d/dt(v)
E=((Fw-Kv)(Fw-Kv)')=FQF' + KRK'
Q = E(ww') and R = E(vv')

The Attempt at a Solution


There is more to this question but I am just having trouble understanding where Q and R come from if w is q and v is 1.

Q is the covariance of the process noise and R is the covariance of the measurement noise.
 
Right but where do they come from? Or how do i calculate it?
 
dmorris619 said:
Right but where do they come from? Or how do i calculate it?

Q comes from the uncertainties in your processs model. R comes from the errors in your sensor.
They are specific to your particular problem.
 
Thats what I am unsure of. All I have is the F matrix and the output. So from this how do I get Q and R unless there is another way of getting the Kalman Equations without Q and R.
 
dmorris619 said:
Thats what I am unsure of. All I have is the F matrix and the output. So from this how do I get Q and R unless there is another way of getting the Kalman Equations without Q and R.

You can use the Kalman filter without Q, but not without R. The values of Q and R should have been data of your problem.
By the way, I think the whole problem is ill-formulated. The state transition F should be square and not a vector.
Can you post the problem in its totality?
 
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