I am working on a project and I ran out of ideas on how to implement one specific part. I am going to throw it here to get any help or ideas. This is not really arduino related question but this forum has been really helpful to me to solve wide array of problems over the years that is why I am going to give it a shot.
So I am trying to convey liquid (more specifically: ink) from a bottle to 4 different bottles via bundle of very thin tubes. Each tube has: ID(inner diameter)=0.5mm and OD(outer diameter)=1.5mm and is 1 foot long.
So It looks something like:
As you can see there is bundle of tubes to carry the liquid. Each bundle will have somewhere around 40 to 50 tubes.
How can I approach this? is it feasible? Do I have to use some sort of pump? How can I connect these bundle of thin tubes to a pump?
Also I want to control the flow of ink to each bottle. What I mean is that I am NOT going to pump into all 4 bottles at the same time. For example, at a given time, I would like to pump into bottle 1 for 1 sec then stop it and then pump to bottle 3 for 2 sec and then stop it. So I thought I might have to use an arduino to control 4 pumps, is this an efficient way of doing it? Or can I design a system that utilizes only one pump?
I have never used pumps before I need some guidance on how to approach this task.
Your main problem is the internal diameter of the tubing and the viscosity of the ink.
Can you make ink flow through the tube under the force of gravity?
If not then you will need a pump that can supply the ink at some pressure.
Otherwise you pressurize the supply tank and use some sort of valve in each tube.
Even going to 1mm internal diameter tubing will make a big difference.
it seems like an X/Y problem in that you have an end goal, of which you are not offering any details.
you have chosen a path for whatever reasons and want to use that path.
with all engineering, you have a known result and a hoped result.
if you pump fluid on each ilne, you know you are forcing fluid into each. this requires either a pressurized tank, or individual pumps.
if you elevate the thank, you can close off each tube, then open each and hope that there is flow. you would have to monitor the flow to know it is occurring.
the end result, a pump or a valve, would require one pin per tube.
it could be argued (rightly) that having a pump does not guarantee that it has power, is connected, has fluid to pump, the tubing is not blocked, etc. But a pump would have a much better chance to push through an obstruction.
With the listed diameter, we would expect a very low viscosity fluid, and a filter that would prevent any blockages.
there are lots of ways to pinch tubing to use the tubing as a valve and not have a solenoid involved.
a periastalic pump can be used to dispense known quantities, but it delivers digital values. 1 unit per chamber, no more, no less. the newer sharkbite type of fittings do not block the isides, but push on or barb fightings have a reduced opening. that said, you can get larger tubing and use an orifice at the end.
a periastalic pump can be used to dispense known quantities, but it delivers digital values. 1 unit per chamber, no more, no less.
The rotor can stop at any angle and the flow stops. Except for the space where rollers press on the tube, the output is quite constant. With precise positioning like a stepper motor, its volumetric control cun be much finer than the chamber volume between two rollers.
I think I recall a similar setup, my feeling is this is for a kind of printer, delivering 4 colour paint on a pattern matrix.
Take a fish tank pump, add a adapter for 4 tubes or make your own one, let the pump start
and pump your ink in the bottles if you want to stop the flow get 4x servo motors and add one to
each tube, the servo motor will push the tube or bend it and stop the flow of the ink.
Any time you can control the flow in the 4x bottles with the 4x servos and the small pump machine.
I'm with Blimpyway above on both counts.
Only difference was I was thinking a gear pump. (same difference really)
Point being, nothing will "run" from the 0.5mm tubing unless forced to do so.
The easiest way to create laminar flow in a liquid is to use straws nested inside a larger pipe. Naturally this necessitates largely straight pipe, at least at the end where you want the laminar flow liquid.
4 such pipes each hooked up to a pump with sufficient flow rate should work, and use the Arduino to control the on/off flow of the pumps.
It IS possible to create laminar flow in a curved tube but it's MUCH more complex (google it so see all the scientific papers discussing it) and almost certainly unnecessary for your project.
