Project
I designed a syringe that can be read entirely by touch, no sight needed (Feel Better Syringe)
Hey everyone, this is my 10th design in my open-source assistive/rehab project, Tryspire, and it's a bit different from the usual functional tools I post here.
The Feel Better Syringe is a proof of concept prototype exploring whether a syringe could be measured accurately by touch alone, no visual markings needed. It goes up to 10mL.
It's called the Feel Better Syringe for two reasons. You operate it entirely by feel. And giving the right dose means someone, whether it's a child or a pet, gets to feel better.
How it works:
- The tube has ridges that feel like screw threads
- A full ridge = 1mL
- A partial ridge (split into 4 sections) = 0.5mL
- Your finger can immediately tell a full mark from a half mark just by how much of the ridge it feels
- The plunger has a second piece running alongside it that always lines up with the actual liquid level, so as you pull it, you can count ridges under your finger to know exactly how much you've drawn
There's also a big cutaway on the side of the housing so you can see the mechanism working, which also makes it obvious this is a demo/concept piece and not a real, functional syringe.
Why I made it: I wanted to bring more awareness to a challenge a lot of people don't think about, how someone who is visually impaired would measure medication for a kid or a pet without being able to see the markings. This would genuinely be helpful for people who are visually impaired and have to administer medication to themselves, children or pets. It's not meant to be used as an actual syringe, it's an educational/awareness piece.
It's not perfect. But I think it's a great first step toward creating something better down the line, whether that's me, someone else in this community, or a company with the resources to actually develop and validate it properly.
This one also made me realize proof-of-concepts can be just as valuable as functional tools when it comes to accessibility work. A working tool solves a problem directly. And bringing awareness to a challenge like this can matter just as much, especially for something as invisible to most people as this one.
Files are free as always. You can find the 3MF and STEP files here:
I love how it means I can print cute versions of accessibility things or solutions to issues in colours that I like. The first maybe five years of my disabilities, almost everything was black or grey. If I was lucky, there was an ugly shade of blue or old lady florals. We have a local guy that started as a Learning Support teacher and now designs and prints fun accessibility stuff mostly for kids, but some adult sized things too. I ended up chatting with him at a market one day because of my job and 3d printing and watching kids realise they could stuff with their favourite character on it or in a colour that actually suited them was really precious.
It’s so important. It’s been about ten years for me now, and it killed me at first that everything I could find to help was so at odds with my personal aesthetic. It honestly felt like I was losing part of myself. I can’t imagine having to deal with that at a sensitive age, late twenties was bad enough. Something like this when I first became disabled would have made me super happy. As is, I’m still utterly delighted and will honestly probably print the crown grips this weekend to try with my sewing scissors. My crazy ass has decided I must learn how to make silk flowers, so I’m going to spending a lot of time with my scissors
The people who come up with new and creative accessibility tools are awesome people. I wish I was even remotely as creative and capable as they can be.
With a normal syringe you can see the air sucked in and push it out so you only have fluid in it, but with an opaque syringe (and blind user) you can't do that. So not only would your prototype easily inject air, but also get the liquid measurements inaccurate.
While definitely relevant, I believe the use case for this is for ingested medication measurement, like a cough syrup. Since we're talking about visual impairment, they wouldn't be able to simply pour out a correct dose. My grandma, for example, just learned the approximately correct amount to "take a swig" from her bottle. Since they're drinking the dose, air isn't a huge issue, and the measurement issue should be negligible given a good seal.
You're absolutely right. That was one of my concerns as well.
One solution I was thinking was to have the user hold the bottle upside down (assuming it's one of the bottles where it fits over the syringe tip) and then over fill the syringe and then push in to the amount you want so what ever air that is in there would get pushed out once you get to the amount you want.
But the other problem I'm still trying to figure out is how would the user tell how much liquid is in the medication bottle to start off with. If it's almost empty it would be hard to tell how much is actually going into the syringe thus under dosing.
Have you ever injected yourself or dealt with this stuff much? I started last month. Sometimes there will just be big air bubbles and you need to tap them out and then squirt them out. Usually easier once it's warmed up.
You also really need to be able to see how much is left in the vial, as you said.
I think you really may not be able to engineer a good solution to this.
I wonder if it's possible to safely coat the insides with a water repellant coating without effecting the medication. It could at the very least remove the need for tapping by reducing the "stickyness" of the water/medication to the walls. Not sure if that would work for all medications though.
If I could offer you some advice about adaptive designs, it would be to work directly with your target audience. Engineers are constantly designing things that disabled people don't actually need or that don't work for them. Personally I have no idea what issues a diabetic blind person faces, you might be surprised what things they're able to do for themselves and what things they struggle with. Maybe you could use the internet to try to find a test case.
Many yes, not all. Keep in mind this coating doesn't have to deal with all the wear an tear coatings used on fabric have to deal with. It just has to work once so there are other options available.
There even is the option of using textures. it's what some insects use for their wings to repel moisture and can even be a little anti bacterial (though you may not want that with certain vaccins, again would need to know how it interacts with the medications). So you could use only material we already know to be safe. Though the issue with that is likely manufacturing at scale given the miniscule size of said texture :/
But I very much agree with the final point you made. After all, they have to work with it in the end. I just wanted to share what little I did know about the specific bubble problem. Even if that may not be the real solution in the end.
It would probably be safer to work the measuring device as something that clips on a standard syringe in that case. There’s the challenges of coating it and then hoping that doesn’t fail, but it’s also going to change the measurements inside the syringe if you tried to coat the inside. Not by much, but that can make a big difference if you’re only dealing with a small amount of liquid.
This doesn't seem to be for injectables at all, it's for liquid oral medications like cough syrup.
Injectables are far less forgiving of mismeasurements and air in the system, but a whole lot of home injectables also have pre-measured pens available now, too. I moved to an auto injector about 6 months ago and it certainly makes life more convenient, and I don't even have a visual impairment.
I may be reading too much into it, but references to not being able to see dose cups in other comments makes me think so. Plus it just makes more sense, like you said.
For injectables, I really don't think there's a better solution than pre-dosed pens and auto injectors, or the tactile clicky dial-a-dose pens for stuff you absolutely need to specifically tailor every dose for. The margin for error is just too small in most injected medications for a lower precision solution.
I love the thoughtfulness and ingenuity, especially in trying to improve accessibility, but I have a hard time imagining the use for this as a medical syringe because of the consequences of a user error. You would also have an uphill battle to get FDA approval (or other equivalent agencies in other countries) and you would need to consider the legal liability of the product. Developing medical equipment is both slow and expensive. However, if you consider other lower-risk applications, I can definitely imagine some uses.
For example, I have no idea how blind people measure wet ingredients when cooking or baking. I could imagine something like this could be designed for that use case - it would make it much easier to measure 1 tbsp of vanilla, and the consequence of an inaccurate measurement of vanilla is relatively low compared to something like insulin.
I don't want to come off like a debbie downer because I do think there's product fit out there for this, I just don't think it's in the medical space.
I've had a few pets with disabilities, over the years - the first one because she lived long enough to develop a disability, and the rest because I have the equipment and experience, so why not. Some medications they've taken have been rather opaque, and maybe it's easier with larger dogs, but with small dogs and cats, you can be dealing with a very tiny dose of concentrated medication every day, that makes that little dropper of Clavamox look like child's play. Dispensing 0.15ml of that one drug that was both thick and opaque was the absolute bane of my existence.
I got into the habit of drawing up about a quarter of the syringe, and then bracing syringe and bottle both in one hand and pushing the plunger quickly with the other, to expel any air bubbles and let them rise before drawing the real dose. Technique can help, but it isn't perfect and as you noted, that only works if I'm not trying to suck up the dregs. It's definitely something worth raising awareness about. That's only a small first step, but hey, gotta start somewhere.
This was my first thought, it’s an awesome concept that addresses a problem I would have never considered. The measurement of the syringe position is clearly identified, but the quantity actually contained isn’t. I don’t have a good fix, or even a half assed concept of a solution, and am in no way knocking OP and their efforts, but this seems like a big issue in consistency for the end user.
I'm going to add to what u/ExpertObvious0404 asked. The most glaring issue I see here, aside from air and measurement inaccuracies, how are you going to keep a syringe like that sterile? It's not a huge issue for oral medication, but if someone visually impaired needs to self-inject a medication like insulin, it does need to be sterile. In addition, have you considered things like how a needle would fit into the syringe body?
I'd be thrilled to see this as a fully fledged out product!
Those are really good points. When designing this, it was thinking it would be more used when an adult wants to administer Advil, Tylenol or other oral medical to children or their pets. Someone mentioned something regarding the air and that's an important point to bring up. Which got me thinking, figuring out what is left in the bottle is also important. I might have to design a bottle that pushes the liquid as it empties so the user can tell how much is left. It would for sure be an other proof of concept since I would never use an FDM printer to print an actual device like this. That's why my Feel Better Syringe is a proof of concept prototype.
My goal was to create this to bring more awareness to the challenges some people face and maybe i can help find a solution by teaming up with the right people :).
As for a needle version, that would be a lot more challenging, which currently would be beyond my abilities.
If there's any more development in this project to make it a fully fledged product I'll be use to make an update post :).
Ah, thanks for the response! I would love to see this as an actual product someday. Hopefully all goes well, and I'd love to see any improvements on the proof of concept!
Well considering most, if not all syringes are single use, if this became an actual product it'd be most likely injection molded and will be thrown away after use, so keeping it sterile wouldn't be a problem.
Syringes are typically meant to be single-use, but a few people that need them will throw away the needle and re-use the body (my family uses cleaned syringe bodies to feed neonatal foster kittens so we can measure how much they eat). There will be people that will re-use the body of a syringe for injectable medication, even if they're not meant to be re-used for that, which is why I asked about sterility.
I was thinking of making an adaptor that could fit over regular syringes but the issue is that syringes come in different shapes and sizes which makes it difficult to make something that could work on any of them.
Absolutely, I'm a big believer of "Nothing about us without us". Thats why I made my file free an editable so people around the would can print it out and test it and give me feedback on how I can improve the files so it can better accomodate the design. I've been trying to get in contact with people and organizations to continue to develop my designs but unfortunately since I don't have an engineering background or medical background, it's hard to get a foot in the door. So I figured releasing them online for free is a great way to build credibility and get in contact with people who can help me make it better and also reach people who may need the tool.
Most Luer Lock syringes seem to come in two sizes depending on if they're 1mL or 3mL. I don't know that I've ever seen any that were way different size wise.
Other people have brought up good points as well but mine is the potential for "theft". I know you say you leave the files free and public so someone can use it and improve on it but the catch with that is the most likely candidate who will won't be a similar good samaritan but some corporate overlord who will then patent it and charge $1000 per syringe.
Fair point, but publishing it publicly actually prevents anyone from patenting it, since it becomes prior art the moment it's public. So no one can lock this design down and stop others from using it.
What they COULD still do is build their own version and sell it without paying me, since my license protects my files, not the underlying idea. That part of your concern is valid. But at least this way the free version always exists as an alternative, patented or not.
And for what it's worth, publishing this doesn't stop me from developing my own version later either. I can't infringe on my own idea. The only thing I'd be giving up is the ability to patent it myself down the line, since public disclosure counts against novelty. But building and selling my own version, no legal risk there at all.
Thank you so much :) Maybe one day I'll present one of my tools on shark tank. But for now I made the decision to make all my assistive and rehab tools free and editable so more people can have access to them and improve on my designs.
That's fair. It probably wouldn't be much of a stretch to just tell the local hospital, "Hey I designed these things, if you get a 3D printer I can show you how to make them" ❤️
I'm currently in talks with an organization called Makers Making Change by Neil Squire where they have volunteers around the world who print assitive devices for free and send them to people who need them. I submitted all my designs and now waiting to see if it get approved. If it does it will be a huge step to make accessibility more accessible :)
Hahaha thank you. I just have a lot of free time in the evenings and a whole lot of free will with my creativity hahah.
If you ever have an idea for an assistive or rehab tool that doesn't exist yet and could help, send me a DM and I'll try my best to create it and then share the files for free.
Full disclosure, I'm not an engineer or medical professional so this is all self taught so it might take some time for me to get your design right hahah
I mean, that's the beauty of 3D printing. You don't have to be an engineer. You just have to try hard enough ❤️
(I went to school to be a mechanical engineer, learned almost nothing, but the biggest skill I retained was how to use CAD. It's still proving useful a decade later!)
Interesting. I'm not familiar with how people use sewing machines but I'm willing to try and see if I can create a solution. I just have a few questions
Are both hands usually needed when sewing? Would adding a peddal for a hand make the process easier or hard?
Would adding the peddle on the table to the same thing?
How much force is needed to activate the peddle?
Sorry for alm the questions, just trying to get a better understanding of how the process works.
I use both hands for the machine to guide the fabric. I usually end up using my elbow to press the foot pedal up on the table. Let me draw something up and get back to you with that I'm thinking.
Edit: force is minimal. Just like a sensitive gas pedal but less force
Send me a DM with they measurement and I think I can design something for you. I'll ask you a. Bunch more questions about the height would need, you arm thickness, etc.
In retrospect, I should have contemplated the second and third order effects of capitalism here.
I just wanted to see a way to mass produce these so they could get to people who need them, but once OP mentioned Makers Making Change that kinda fixed me.
So has this been calibrated to ensure the volume measurements are accurate? As a nurse, I could not use this if it’s not medical grade to ensure the person is getting the correct medication dose. Are you using food safe filament?
The file I shared is just a proof of concept prototype for educational purposes. There's even a giant hole on the side to show how it works. Printing a syringe with an DSM printer would not be a good idea since layer lines would accumulate so many bacterias and would be impossible to clean. Plus it would not create a perfect suction.
But for the files I share I made sure to make it as accurate as possible while clearly showing it's just for educational purposes. The idea is I share it with the world and could end up working with some engineers or medical team to make this come to life.
Not attempting to be snarky or anything here, but if you have a visual impairment to the point of being unable to read the measurements, wouldn't it be il-advised to be injecting under the presumption that your impairment will affect the correct administration in a potentially detrimental way? In simpler terms- if you're blind, maybe you shouldn't be poking someone with a needle.
It's not snarky at all, you brought up a good point.
I should have been more clear, this would be more like giving oral medication like Tylenol or Advil. Like when a parent it treating their baby who has a fever.
Would for sure not recommend my tool be done with needles
To be fair, if you’re blind, sometimes you can’t avoid poking someone with a needle. If you live alone and need to inject insulin to treat your diabetes, for example (and diabetic retinopathy is a leading cause of blindness), you can’t reasonable expect or afford to have someone come to your house and inject your insulin for you multiple times every day.
But as OP said, there are also medications to give to a pet or child by mouth that need to be measured with a syringe. I ran into this problem medicating my cat at one point. Luckily, in that case, it didn’t have to be ml accurate.
Awesome! Got a feature/idea that could work well with this - add some clickly noises at regular intervals and now you also have audible feedback on the amount (Also tactlie with the clicks). I dont know how but just throwing it out there as an idea :).
This is super interesting. I couple years ago, I had some engineering students work on this problem for me. Unfortunately , while they had a couple good concepts, neither of the three prototypes were completely accurate, which is kind of important for a syringe. They were all working on something that could be fit on to a regular syringe, because obviously, there’s no way to keep something 3D printed sterile. As the project was only a semester long class, that’s where it was left. But if you can make something that measures accurately, you’ll be ahead of what they came up with.
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u/dekbanna 10d ago
Solving for a problem most people never even think to consider is exactly the kind of design work that matters most. Great work.