Quote Originally Posted by Anuvin View Post
Ask 10 engineers for a solution...

I have never spent so much of my time thinking about valves. It's tempting to use stepper motors with the peachy printer, in similar and entirely different methods than the ones presented by cephdon, but electric motors are troublesome devils. Look into motor issues with 3d printing, you will find plenty of scary stuff. One of my favorite things about this project is that it contains no motors. That feature alone differentiates the Peachy printer from all others, and I intend to maintain that perspective for as long as is reasonable.

Is it possible to use more than one drip counter on the mic line? If so, we don't have to bother with flow rate, motors, OR in-line valve mechanisms. We would still need to make a valve, but it can be in the reservoir itself, alleviating some typical leak problems that you get with in line valves. Same peachy printer, just with 4 reservoirs instead of 1, or a single reservoir with 4 outlets. If each line were set for sequentially faster drip rates, you can combine them for a large variety of speeds. For example, if line 1 drips 1 per second, line 2 drips 2 per second, line 3 drips 4 per second, and line 4 drips 8 per second, you get every speed from 1 to 15 drips per second. 15 steps of speed is good enough for me, I should think.

I think a pot and float is a really good idea. My fear is that it would take too long to respond. A float is a bit reactionary, compared to counting the drips. Then again, drips are inconsistent, so that may be less accurate than a float/pot could be. Please share any designs for the float you may have, I know I'd like to see them.
Just how can we get the float reading back to the software, without changing the design to digital? Also, the resolution of a float and a potentiometer would be poor and very unreliable IMHO. We only have to remember the volume controls on our old audio devices crackling as they lose contact with the potentiometer track. A much more reliable measure of depth and which would have good resolution, is an ultrasonic transducer, bouncing a sound wave off the surface of the liquid. Same problem though, no way of getting the reading back with an analogue Peachy.