Electroosmotic Pump Progress

I am feeling like I might need to switch my focus from making an easily DIY-able 3D printed EOP. While I believe it is still possible to make a larger homemade EOP with relative ease and cheap materials, one of my core goals is to encourage others to make and use the design as well. Based on a decent amount of research I’ve done this week, I believe the required voltages are too high for the scale I’d like to make these pumps at, thus maybe too dangerous for a DIY kit.  For the size I want to make the pumps at, the voltage would live around 250 volts at 5 amps. While this is disappointing, I would still like to continue this project with a focus on general exploration of EOPs without an end goal of encouraging others to try it. I’m not fully sure if this is a summer project or the new focus of my final.

One very helpful research study I found for 3D printed EOPs is this one. The study focused on 3D printing techniques for the filter of the pump. The filter needs to be very fine, usually fritted glass filters are used. This increases the surface area while also creating a required pressure to pass through the filter. These researchers used a “log stacking” method where they modeled a bunch of cylinders sitting on top of each other, utilizing the space between the circles as filters. As a first test this week I produced some 7mm diameter filters using this method, and while I have not tested them in water, I can see lots of little tiny holes.

This is also a video that I found very helpful to wrap my head around EOP’s in general.

I am aware I may need to pivot ideas for my final, and I do have another idea, but I need to refine it more. It would be living much more on the art side of the spectrum of soft robots, not serving a utility. I’d like to make a silicon mold actuated by 3 or 4 of the bulb air pumps. The general shape of the mold is inspired by a flower bouquet in that it is comprised of varying shapes bunched together. The different hand pumps will actuate different elements of this mold, and the pressure along with various shapes will allow unexpected movement. Ideally, this would be engaged with by multiple people at once. Like I said, I need to chisel the idea out a bit more, but it’s approaching something I am excited about.