Science Project

Intro

I'm starting a project to do some interesting experiments, so I thought it'd be fun to document them here. I guess for this first post I'll describe what I'm planning.

So this is sort of one of those yak-shaving type stories. What I mean is that I started a project that ended up leading to a different project. So I wanted to create a wearable device that straps to your back, and can detect if someone is behind you and relay that through haptics. Now, I thought the detection would be the really hard part and the haptics would be easy, but it turns out I was completely wrong!

I mean, I guess the haptics could have been easy if I was willing to settle for what's easily available, but I got stubborn :) The crux of it is that I didn't want vibration. This device will often be giving near constant feedback, and vibration would get super annoying/irritating. I wanted something that could produce a gentle touch. Something that wouldn't constantly stand out, but you could feel it when you thought about it. Like, when you wear a necklace you aren't constantly aware of the feelign of the chain, but you can feel it if you think about it. But I couldn't find anything that fit my self imposed size contraints. Even tiny linear actuators would add like 20mm of thickness to it, and I don't want it to stick out under your shirt and look weird.

This led me to getting caught up reading research papers on the topic. and I came across a pretty amazing one from just last year (2025). In this paper the authors created a full "Freedom of Motion" actuator. something that not only pushes straight down on skin, but can also generate directional sheer force! The clever way they achieved this was by placing "tri-nested coils" above a neodymium magnet. The tri nested coils were so clever! each one is oriented a different direction, so you can generate fields in any direction, or even combine them to move orthogonally.

This inspired me to try something else, something that as far as I can tell no one has ever tried before. I want to apply the tri-coil to MR Fluid. MR Fluid stands for Magnetorheological fluid, and it's a non-newtonian fluid that changes viscocity when a magnetic field is applied. Basically stick magnet near it and it turns into a near solid. I'm soooo excited to see what effect a tri-coil has on it! I think no one has tested it because the tri-coil is such a new thing - I'm pretty sure last years paper was the first to apply it. This is what has me most excited - doing science thats NEVER been done before! I've always wanted to do that. I've always wanted to actually contribute something novel to the scientific community. And I know I may not make any cool discoveries. But by doing the research maybe it would save someone time of repeating it pointlessly. Or maybe it would inspire them to do some variation on it. Of course, the trouble is I have no way of publishing it as far as I know. I'm not with a uni or anything, and I'm pretty sure publisher won't accept papers from some rando doing home experiments. But that's a problem for another day.

here's my basic plan

My first goal is to replicate the results of the study that inspired this. I'll make the nested coils the the same (or at least as close as I can) specs as the study, and see if I can move a neodymium magnet the same way they were able to. That way I can know if my set up is correct.

Step 2: observe variations
My goal is to study the effects of the tri-coil on MR Fluid. I feel like I need to do some testing and ovservation before I can really nail down a good hypothesis for a proper experiment. So this step is all about playing around and seeing what happens!

Step 3: develop hypothesis
So I'm not an expert in electrical engineering or physics or any of the things that would really qualify me to actually do this stuff. Because of that I'm not likely to come up with some hypothesis about complex modeling or deriving equations or anything like that. My hope is that a tri-nested coil can be used with MR fluid to enhance haptic feedback. My hypothesis will likely be something roughly like that.

Step 4: formal experiment
Once I have a hypothesis nailed down I'll try to plan and execute an experiment to prove or disprove it. It's very very important to me that my goal is to test the hypothesis, NOT to prove it true. Trying to prove it true is a very bad approach that leads to bias and bad results. I'll have to think about the best way to document these experiments. I'm not sure if I should just use a plain text file or some kind of markdown or maybe a scientific notebook format?

Step 5: Iterate
I'm hoping to be able to create and test more than one hypothesis. I already have ideas for some variations I can do after this initial study.

Sorry for being such a long intro. Thank you so much for reading this far, and I hope you are as interested and excited as I am for this project :)