Measuring the volume of urine (or liquids) and monitoring it at bedside or central station of units at hospitals
are very important.
In my design, by a simple and cheap way we can monitor the volume of urine and liquids.This design is independent of cylindrical container for each patient. In comparison with current ways and monitoring my design is more effective, precise, simple and cheap.
Also, it can be used to measure all liquids.
So, as you can see in Fig.1, I used two pairs of ultrasonic sensors, that should be as the type used in sonography or echo cardiography equipment for their sensitivity and precision. One Height/Y sensor to detect the height of cylindrical container at the first, when press s1 key of the set before entering liquid or urine into it that is; H. And a Radial/X sensor to detect the radius of that container. Then, a LED blinking informed that to press S2 key and set is ready to measure volume of entering urine (liquid).
Finally, we have; [see Fig.2]
(t / 2) = s * Vs & s = Vs *(t / 2) Formula (1)
s is distance,
Vs is speed of sound (In dry air at 20 °C (68 °F), the speed of sound is 343.2 m/s) &
t is the time of the sound travel flight and its reflect, so should be divided by 2.
tR=time of X sensor and extract radius of the cylindrical container by formula (1)= R.
tH=time of Y sensor and extract height of the cylindrical container before entering urine (liquid) by formula (1)= H.
td=time of Y sensor and extract height of the cylindrical container after entering urine (liquid) by formula (1) = d.
Now, we can calculate the height of the urine[liquid]in the container by formula( 1) ; X=(H-d) , [see Fig.2]. The volume of the urine (liquid) are: [Vx=(3.14)(R*R)*X]. [volume of a cylinder is; V = ?r2h].
Container should be cylindrical and can be thrown away and is one consumption.
We can use PIC18F8722 with xtal=40MHZ crystal or dsPICPIC33FJ256GP710A with xtal=64MHZ crystal and uC compiler sending it to central station and bedside via RS232 or RS485 (and also displaying it on T6963C GLCD or TFT of the set