Clean Air Bubble - Your Safe Atmosphere to Wear

In this Instructable I will describe how you can build a ventilation system into your clothes that will provide you with a stream of clean and filtered breathing air.

Two radial fans are integrated into a sweater using custom 3d-printed parts that each carry an air filter. Short tubes connect the fans to nozzles at the front of the hoodie through which the cleaned air is streaming to nose and mouth, keeping the environmental air away from your face. A fast rechargeable battery pack powers the device for more than five hours, so you always have your personal clean air bubble at hand.

Disclaimer
This device won't protect you from any airborne diseases! This is NOT a medical device nor was it tested under any scientific circumstances. Do not use this as medical protection!

Step 1: Tools and Parts

You should have access to the following tools:

3d printer & PLA (longest edge length < 12 cm / 4.7")
soldering iron
hot glue gun
sewing kit

The following parts are more or less essential:

Piece of clothing with hood (I'm using a sweater from a thrift store)
2x radial fans (here it's two Nidek Gamma 28)
Air filter fabric (medical supply store)
Short tube (less than 10 cm / 4")
Battery pack (mine is from a broken Bosch drill with 14.4V / 2.5Ah)
Step-Up-Converter (for up to 24V)
power switch
4x M4 screws and nuts
Threaded nuts (4x M2, 4x M3)

Should you need to modify the custom parts, you should also have Autodesk Fusion 360 or similar CAD-tool on hand.

Step 2: Print the Necessary Parts

Overall you will have to print eight items for the ventilation system plus two more holding the battery and electronics.

Download the STL-files, slice them appropriately and fire up your 3d printer. Total printing time for me was around 8-10 hours using the following settings:

Material: PLA (black for visible and white for hidden parts)
Infill: 30%, Layer height: 0.2625 mm / 0.1"
Support: Yes, Adhesion: Yes

All parts were designed in Autodesk Fusion 360, sliced with Ultimaker Cura and printed on the inexpensive Monoprice Select Mini V2. Feel free to modify the layout so it will meet your requirements in dress size and available materials!

After printing you should sand down the parts to avoid any skin irrtations and to have the optimal air flow.

Step 3: Mount Fans and Filters

At first you should setup both fans:

Use the soldering iron to insert threaded nuts (M3) as shown in the picture
Bring each fan and the two halves together
Add two M3 screws to secure each fan construct

This device must be washable, so all electronics and filters can be removed. Only the base plate is fixed permanently to the clothes as described in the following steps:

Cut two holes with diameter of approx. 5cm / 2" into each side of the sweater's hood
Use hot glue to connect the fabric to the base plate which has a raised gutter that will hide (and secure) the cutting edges
Sew the base plate to the cloth for extra support*
Mount the fan onto the base plate using M4 screws and nuts

* I am fairly inexperienced in the art of sewing. Sorry for the mess!

Step 4: Add Air Nozzles and Tubes

To transport the air stream to mouth and nose you will need to:

Sew the nozzles at three points to the hood
Cut the tube to length connecting each fan to the corresponding nozzle
Connect nozzle and fan

In case your piece of clothes has an inside layer (as shown in the pictures) you can hide fans and tubes so that only the nozzles will be visible from outside.

Step 5: Assemble the Electronics

A step-up-converter transforms the 14.4V provided by the battery pack to the 24V that the fan is running on:

Cut a washer in two halfes and glue it into the battery clip
Attach the power switch to the case using hot glue
Solder a wire to each half of the washer (use more glue to ensure insulation)
Connect one wire to the switch, the other goes directly to the IN-pins of the step-up-converter
Add a wire from the switch to the remaining IN-pin of the converter
Add two cables connecting the OUT-ports to both fans
Use the soldering iron to insert the threaded nuts (M2) into one half of the electronics case
Screw two M2's to assemble the case

This step highly depends on the electronics you are using. One half (having the clip) is highly customizable and will fit many other battery solutions. Save resources and use whatever battery pack you have available!

Step 6: DONE! - Some Final Words

Congratulations - you're done!

Engineering this device took me a lot of time but I love the idea of having a clean and somewhat safe atmosphere around me at all times. Future designs might improve the air stream as well as the wearing comfort and add new features like pre-heating and moistening the air flow.

Please feel free to get in touch with me if you have any questions, recommendations or want to discuss your improvement ideas!

Thank you for following along and see you next time!