u/Solarbg

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:

Thingiverse: https://www.thingiverse.com/thing:7397662

Printables: https://www.printables.com/model/1815346-feel-better-syringe-tactile-dosing-for-the-visuall

Maker World: https://makerworld.com/models/3190738?appSharePlatform=copy

Creality Cloud: https://www.crealitycloud.com/en/model-detail/6a8522aee2371c959ea56a8e?cloudPlatform=19

Happy to answer any questions about the design or mechanism!

I posted the original Owl-Reach a while back, a clip that mounts to underarm crutches so you can carry a grabber tool hands-free instead of holding it or letting it dangle. Since then I got a lot of comments and messages from people saying "this is great but I use a walker, not crutches" so I've been wanting to make one for a while.

Funny enough, what finally made it happen was finding a walker at Value Village. I picked this one specifically because it's the standard hospital-style/two-wheel type, which is the most common walker I see people using, so it made sense to design for it first.

The Walker Edition clips onto the frame in seconds. Same idea as the original: it turns your walker into a hands-free tool station so you're not trying to balance a grabber while you move. It's built for a 23mm bar, which covers most hospital-style and two-wheel walkers, and if yours is a different size you can scale it in the slicer or tweak the included STEP file.

A few notes from testing:

- Print it in TPU 95A, it needs the flex to snap on and off easily

- A strip of rubber tape on the inside of the clip helps a ton with grip against metal frames

- Most people can fold and store their walker without removing it

- If you want extra stability you can print two and mount them on both sides

Forearm crutches are next on my list, I just need to get my hands on a pair to design against properly. I don't like guessing dimensions when I can test on the real thing.

As always, this is an experimental design, not a medical device, so if you've got specific mobility needs it's worth running it by whoever you work with (PT, OT, etc.) before relying on it.

Happy to hear feedback again.

Here where you can download the free files:

https://www.thingiverse.com/thing:7383749

https://makerworld.com/models/3056179?appSharePlatform=copy

https://www.printables.com/model/1782521-owl-reach-walker-mounted-grabber-clip

https://www.crealitycloud.com/en/model-detail/6a58570131674c1f4bbba05c?cloudPlatform=1

Hey everyone,

I just wanted to share my latest design that I just released.

Like most of my assistive and rehab tools, I don't have a need for this one. But someone commented on another post about struggling with round doorknobs, and that got me thinking. I did some research and realized the real issue: when people travel to different places, they interact with all kinds of doorknob types (mostly an issue in North America) that just aren't accessibility-friendly. Luckily as a society we're moving away from round doorknobs but they are still present in certain buildings and homes.

So I designed the Door-O-Clock to address that. It's an adaptive tool that works on most common knob styles (Plymouth, Oval, Orbit, Tulip, ball-style, etc) so you're not stuck dealing with whatever unfamiliar doorknob you encounter.

The tool has two rotating parts that work around the doorknob like clock hands. The big hand rotates to open and close the door. The little hand rotates to handle locking and unlocking from either side, and it's designed with four different features depending on what type of lock you have. There's a claw-shaped end for thumb-turn locks and push-to-lock mechanisms. On the other end, there's a split peg where you insert a toothpick to reach pin-hole emergency releases, plus a thin blade for slotted locks. The Big hand has a slit at the bottom that makes picking up the toothpick more easy.

You add adhesive grip tape to the contact surfaces so it grips both the knob and your hand. It's portable, so it's great for travel. And honestly, the best part is you never have to pinch anything.

It's not meant to stay on the knob permanently because TPU can lose elasticity, but that's actually perfect for the travel use case.

This design isn't perfect, and I'm definitely open to feedback. The community feedback I got on the Bee's Knees really helped me iterate and improve, so I'd love to hear what you all think about this one too.

The files are free and open source, and a STEP file is included if you ever want to make changes or adjustments for your printer. You can download them here:

Thingiverse: https://www.thingiverse.com/thing:7376696

Printables: https://www.printables.com/model/1768509-door-o-clock-assistive-doorknob-lever-with-lock-co

Maker World: https://makerworld.com/models/2993509?appSharePlatform=copy

Creality Cloud: https://cp.crealitycloud.com/en/model-detail/6a4356d68561ea1696d28137?cloudPlatform=1

Curious what people think.

TL;DR: I designed a feeler gauge style device to measure the gap between your thumb and fingers (it's an occupational therapy and physiotherapy device prototype). Some people have trouble bending their fingers

I just designed and 3D printed Petal Pinch, a stackable petal gauge for thumb opposition testing.

The concept started with a milk bag tag and evolved into a gauge with rotating petals that gives tactile feedback while tracking thumb mobility.

How it works:

Hold it in one hand or place it on the table and try to pinch the exposed petal with your other. If you can touch it, slide that petal under the hummingbird and try again. The assembly stacks to about 50mm with 10 petals at 1mm and 4 petals at 10mm. I printed them in alternating colours to make tracking easier.

Learn more about thumb opposition scoring: https://mobilephysiotherapyclinic.in/kapandji-thumb-opposition-scores/

Why petals:

It's inspired by the "loves me, loves me not" petal game. Also added a little humming bird design to bring the theme all together (it's also used to store the petals).

About tolerances:

3D printing 1mm petals accurately is tricky. You'll likely get 1.05 to 1.15mm depending on your printer. I'm including a STEP file so you can adjust dimensions to match your output. So you might have to print the petals a few times to get it somewhat right.

Important:

Just to be clear this is not a medical device. I just design and 3d print devices that could potentially help people. There were no clinical studies or tests that were done when developing this device just a whole lot of trial and error and online research.

Hopefully this can help someone out. And by all means of you have any suggestions on how I can make it better, let me know. I'm always down to improve my designs.

Thank you,

Free Files available on:

Thingiverse: https://www.thingiverse.com/thing:7355682

Printables: https://www.printables.com/model/1725865-petal-pinch-thumb-opposition-gauge

MakerWorld: https://makerworld.com/models/2820455?appSharePlatform=copy

Creality Cloud: https://m.crealitycloud.com/en/model-details/6a0be3dee0b3fd73ac34b421

Edit 1: think of this device like a filer gauge. It measures the gap between the fingers when you try to make your thumb touch other fingers. The maximum distance this device does is 50mm which most people can do if they are suffering from a hand condition that limits their gripping mobility. The goal of this device is to keep reducing the gap between the fingers until you get to hopefully 0mm.

Edit 2: here's a video of it being used : Petal Pinch - Thumb Opposition Gauge (3d printed) https://imgur.com/gallery/GVWNwW8

Edit 3: to be more clear some people find it difficult to close their hand or bend certain fingers. So through Occupational Therapy and physio therapy they can do the exercise to practice the finger mobility to try and close them. In most cases they use the thumb as a reference point for contact with other fingers.

I'm working on a stackable functional assembly where dimensional accuracy matters, and I'm trying to dial in my Prusa Core One to get closer to nominal dimensions.

I printed simple test features designed as:

- 1.00 mm

- 10.00 mm

Measured with digital calipers, I'm getting:

- 1 mm feature → ~1.05 - 1.12 mm

- 10 mm feature → 10.05–10.14 mm

The problem shows up when stacking parts:

- 10 × 1 mm parts + 4 × 10 mm parts should equal 50 mm total

- Actual stacked height goes over 51.2 mm

That 1.2 mm cumulative error is too much for the assembly to work.

**Current settings:**

- 0.4 mm nozzle

- Creality Hyper PLA

- 230°C nozzle / 65°C bed (bed temp helped a lot with warping, even after washing the plate)

- 15% gyroid infill

- 4–5 perimeters (accidentally left high, usually run 2–3)

- Default Generic PLA profile in PrusaSlicer

**Questions:**

1. What should I tackle first to reduce the oversizing? Flow rate? Horizontal expansion? Pressure advance? Fewer perimeters?

2. How accurate can I realistically expect 1 mm features to be with a 0.4 mm nozzle and Hyper PLA?

I know FDM has limits, but I'd like to get as close as possible to nominal dimensions for functional stacking parts. Any direction appreciated.