Recent content by toolpusher123

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    Solve Mass-Spring Model: Find Shear Force

    Stiil pretty much stuck with this one? Using Housner paper the max shear force that can be produced by the half filled tank is; T = 2*π√m/k ∴ T = 2*π√500/1000 = 4.443 seconds. This is the period of oscillation therefore shear force F = (2*π/T)/m = 500/(√500/1000) = 707.1 N. The answer given in...
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    Solve Mass-Spring Model: Find Shear Force

    Yes you're correct, T (period of oscillation) = 2*π√m/k. Therefore F (max force produced) = (2π/T)*m. I'll have to σo through the paper properly & post once I have a more thorough understanding. Thanks for your input, back asap...
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    Solve Mass-Spring Model: Find Shear Force

    It's not 100% clear to me either, but if you look at page two of the attached .pdf below. It seems that what I've been given is a simplified model where the mass of the water (m) is 500 kg & the equivalent stiffness of the building is (k) 1000 N/m. It then asks me to find the shear force? pdf...
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    Solve Mass-Spring Model: Find Shear Force

    Homework Statement A half-full water tank mounted on the top of a building is modeled as shown below. Find the shear force it can produce? m = 500 kg k = 1000 N/m model: https://app.box.com/s/qke2kbwag2mp9a23kkqq Homework Equations Transfer Matrix Method: Point & Field Matrices...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    No my post was in response to your post (post # 87). My solution regarding my system i.e. K1 = K2 was to find the open-loop tf. The equation I used to do this was: https://app.box.com/s/arwnrxwopi6y2cjls42q Did I enter an incorrect tf in order to plot 'root locus' of system when K1 = K2 ? Is...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    In response to 'milesyoung' post #87; Closed Loop Tf: https://app.box.com/s/twk1h23blxebgawzaw7d Characteristic Equation for post #87: https://app.box.com/s/qivkcx0b0csz6xx8oe8e Miles I have submitted my report. I must thank you for all your help & suggestions. Now that the project is...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    G(s): https://app.box.com/s/s7szsp7rztjndh58oolc H(s): https://app.box.com/s/8hn2fryguhnis8mr0469 F(s) open loop tf when K1=K2: https://app.box.com/s/arwnrxwopi6y2cjls42q Root Locus of F(s): https://app.box.com/s/wzaupxumo3j96lvjwobo 2nd Order Approx K1=K2...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    -K1*H(s)*(G(s)/1-H(s)*G(s)*K2s ? H(s) = 2/(s+2) G(s) = -0.125(s+0.452)/(s+1.25)(s^2+0.234s+0.0163) Therefore as I originally said , find closed loop of H(s), G(s) & -k2s the open loop is then: the closed loop above * -k1 Root Locus Plot: Open Loop Bode Plot...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    But that's exactly where I'm stuck, I've done everything but I'm not sure how to get the 'open loop' with velocity feedback i.e. K1=K2. For the 1st system you just multiply : -1*2/(s+2)*G(s) But how do you work out the open loop tf with velocity feedback? Not sure how to deal with the closed...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    Does the above represent the 'open loop' tf when the system includes K1 & K2?
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    One last thing I was going to ask, as I've asked you countless questions so far. Is for Q6,7 I've got to repeat the earlier Q's i.e plot root locus & do the 2nd order approx. This time I include (-K2s). I've been trying to resolve the TF I should use. Till now it's been 'open-loop', Would I...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    No. Are these markers of the gain (K)? I've tried to move them in order to adjust the reponse but it just becomes totally unstable? Edit: moving the 'pink dot' to -1+/- 2j I've reduced the Ts to under 4 secs but the PO is 22.6%. Does this mean I would have to use the same process again to get...
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    When I produce the 'step' response, the overshoot is gone but it still has a settling time of 36 secs. How would I go about reducing it to the design specs?
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    How Does Unity Position Feedback Affect System Dynamics in Control Theory?

    I get the exact same plot as I did before, with no intesection at s = -1 =/- 2j ? In the example above for C, it shows the zero as s = -1 ? Is this the value I should be using, as I've been using s = 1.58 ? If I use the s=-1, then I get a plot that quite similar but with the intersection at s=...
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