Research inline filtering options for tubing to improve sensor life

[jasonwebb]

Connecting a pressure sensor directly to a person's mouth via a tube is bound to lead to issues and potential safety issues.

I've learned that other commercial sip-and-puff devices use disposable, user-replaceable filters between the mouth and sensor to capture saliva and other bits of matter before they can reach the sensor.

Not only would this improve the life of sensor, it would also (more importantly) make the device more hygienic and safer to use over time. Seeing as this is a DIY, "for fun" kind of project, I don't think this necessarily needs to be a medical or commercial-grade solution, but it's definitely something I'd like to learn more about and pass along to fellow hackers.

[jasonwebb]

• https://www.liberator-international.com/sip-puff-breeze-replacement-inline-filters

[jasonwebb]

Note to self - search for replacement parts for existing commercial sip-and-puff devices.

Here is what other DIY sip-and-puff systems have sourced:

• LipSync uses a neat stepped male Luer Lock connector to connect to nearly any size of tubing, along with a disc-shaped hydrophobic filter - both available through Qosina. Unfortunately, it looks like Qosina does not sell their products to individuals, though the LipSync folks do resell replacements through Makers Making Change.
• FLipMouse uses this interesting Stick / Straw from QuadJoy, which is essentially a larger-diameter tube with a replaceable cylindrical filter in it.

I will plan on buying both the a disc-shaped hydrophobic filter and a Stick from QuadJoy for testing in a while. If I can find an alternative source for the stepper male Luer Lock connector I will also grab one of those, since they seem very useful.

---

QuadJoy "Stick / Straw":

Disc-shaped hydrophobic filter:

[jasonwebb]

Here is what is available for various commercial sip-and-puff devices:

1. Breeze from Origin Instruments

   • Replacement Mouth Tube - a tube with a stainless steel forming wire inside
   • Gooseneck Replacement Mouthpiece - includes an inline filter
   • Replacement Inline Filter

2. QuadJoy 3 Mouse

   • Stick (Straw) and replacement saliva filters
   • Disc-shaped hydrophobic filters