[Cdavis]

@neilh20 so the board here is called a MKS Base V1.4 if i remember correctly. It’s an old 3d printer board. There are a slough of options and which is used really doesn’t matter. They are all, like the mayfly, a modified arduino. Though these use the arduino mega as their main design.

I have the relay controlling the power to the board itself. The power source is still TBD. These board generally take in 12v or 24v. A separate charge controller and 12v battery could make quick work of this task. Though if there are regular maintenance visits, then there is potential to just swap out batteries. The battery basically just needs to sit idle, until sampling, in which case someone should be on the way to pick it up. battery swaps can occur then too. Just off the top of my head I’m thinking maybe a 12v 5ah battery, or the very easy to get 12v 7ah battery. Another option might be tool batteries with and adaptor. This would make swapping things out very quick and wont allow for it to be hooked up incorrectly. Something like this.

This is a lot of spit balling.

 

[Cdavis]

@neilh20 For my sediment machines I use a high torque 920z Nema 17 motor and is rated for 3.36v and 2.1amps. It works very reliably. The one I prototyped is a 76oz Nema 17 which is rated for  4.2v and 1.5amps. I have a pancake motor as well but they are lower torque. Here is a reference to a number of steppers from the 3d printing side of things: here

Generally the biggest issue is to balance the torque of the motor, the fit of the printed pump head, and the feed rate for which you move the motor. In that gcode I provided above, there is two steps to the sampling stage. The pump first moves (G1 E10 F400) tens step at a feed rate of 400. Then is moves faster, (G1 E200 F1400) moving. When reversing the pump it does this same two stage process. I found that it helps reliability and believe it takes full advantage of the torque the motor provides. I could be missing something but this is what I have experienced with this particular pump design.

 

 

 

[Cdavis]

@heather, I would consider that. I still need to figure out the details on implementation and code.

[Cdavis]

The pump project that I used can be found here: https://www.thingiverse.com/thing:3148717

Marlin: https://marlinfw.org/

Here is how I currently put this strategy into action. A wifi connected outlet turns the machine on and off.

https://youtu.be/c7tz9yOD6Wc

[Author]

Posts