Recent content by backstance

thanks for that, useful!

that explains it, thanks again! :)

thanks williej, good mechanical solution. Why do you need the "zero" flow of water though? Is the urine flow too weak to make the rotameter float rise or something like that?

I had this idea, based on dadface's suggestion... could we have the patient urinate into a bucket of known dimensions and then use a weight transducer to measure the (changing) mass of that bucket, then an op-amp differentiator to differentiate it into mass flow rate? Then we could find Q =...

Dadface: indeed, we had thought of weight reduction measurement, but you need high accuracy transducers, since the weight reduction is minimal. but in fact the prototype we're building will be tested with water coming out of a gardening can or similar, so it has to be direct measurement...

thanks for that digoff, useful paper. i'll try to renegotiate our budget and see what i can do. although I am still confused about how sensors are integrated into flow, as in, you don't just put a pressure sensor immersed in urine... how is it connected? thanks to all for the help :)

sounds like a solution! but that would require user input, and somekind of feedback, as well as the container to be volume labeled, etc... whereas just plugging pressure or height change readings into MATLAB would be a little simpler, but I don't know how to connect the transducer to the flow

hi everyone, thanks for the ideas, they're all practical solutions. Q_Goest, i had thought of something similar to what you suggested, although it's more clear now that you've suggested it. The only complicated issue is the geometry of the float itself, and how exactly it could be made to rise...

indeed that's the simplest solution, but 1) that gives the average flow rate 2) it requires calculation after the measurement, which is in disagreement with the requirements, which are for the patient to self-measure their flow rate directly via some calibrated scale or similar... but yes, at...

Hello :) For a undergrad design course I'm asked to design and manufacture a device for measuring the peak urine flow rate to indicate possible signs of prostrate cancer. Basically, the allocated budget is too low to use any electronics (transducers and data acquisition), which was my initial...

any ideas? any help would be appreciated, thanks!

Homework Statement use thevenin's theorem to find the current in the 3 ohm, parallel branch, resistor http://img217.imageshack.us/img217/909/img0267cc7.jpg Homework Equations Thevenin equivalent circuit, voltage divider ruleThe Attempt at a Solution I don't think its possible, since...

thanks I've got it... I = V/Z... z= r+j(wl).. just didnt realize it's that simple.

Homework Statement It's a simple AC circuit with a 100ohm resistor and a 10mH inductor connected in series. The voltage is given as a function rather than a quantity: V = 20sin (5000t). Problem asks to find the peak current in the circuit. Homework Equations i = integral (V/L)dt Z = sqrt...