The new and improved bubble display

I redesigned the bubble display to address some of the issues I was having with the previous version. Hit the jump to see what I changed to make it work.


One of the big problems I had in the previous version was that opening all eight air valves at once yielded dramatically smaller bubbles than opening just one. To combat this I added two large glass chemistry flasks to act as an air reservoir. I drilled a bunch of holes in to rubber stoppers so that I could run all the air lines into the glass. This worked out nicely because the rubber grips the air tubes securely without the need for hose barbs while creating an airtight seal.  I used two flasks because I couldn’t put enough holes into a single rubber stopper to support all the solenoids. To help keep things even, I ran an air hose between the two.  I am not sure if really makes much of a difference, but all the lines coming out of reservoirs running to the solenoids are all the same length. In the previous version I cut them to different lengths to make everything look a little bit more organized. I speculate that since air is compressible that this might have resulted in slight variations of air pressure running to the solenoids and consequently variations in bubble size.

The second big change is the addition of vinyl tubes to hold the liquid. The previous version had one large tank to hold the liquid with little dividers inserted to keep the bubbles on the right path. Now each solenoid gets its own length of clear vinyl tube. This makes a huge difference. Now when I force bubbles into the tubes they rise at a steady rate independent of the size of the bubble. The key seems to be making sure the bubble is large enough that it contacts the walls of the tube on all sides. Another thing is making sure that the bubbles are not formed too close together. There seems to a minimum gap that can exists between bubbles. Any closer and the trailing bubble will be sucked up into the leading one and collapse into one larger bubble. With mineral oil the minimum gap is acceptably small.

One thing to note about the new setup is that the amount of liquid displaced by the air is now much more noticeable. In fact, while I was initially calibrating the printing algorithm I increased the duration of time that the solenoids were opened for each bubble. That made for bigger bubbles, which made for more displaced liquid. At that point I had the tubes filled with blue colored water instead of mineral oil. Long story short, I now have blue stains on the ceiling in my study.

All in all I really like the new setup. It is much easier to work with since the check valves fit right into the vinyl tubes and make a wonderfully secure water tight seal. Plus with the tube there are no longer any worries about leaks along the seams (because there aren’t any). One problem I did have with the vinyl tube is that it comes wound up onto a drum and when you pull it off it wants to curl back up. To fix this I cut it into lengths, stretched them out on wooden dowels and then hit them with a heat gun until the curl relaxed. This is a functional solution, but it is really slow. If I do a bigger version, I will probably need to come up with a better solution.

In case you missed it here is the thing printing out the letters VML

About these ads
Tagged , , , ,

25 thoughts on “The new and improved bubble display

  1. [...] emailed in to show us how he has improved his bubble display since the last time we saw it. If you recall from last time, he was having issues with the air pressure dropping when multiple [...]

  2. [...] emailed in to show us how he has improved his bubble display since the last time we saw it. If you recall from last time, he was having issues with the air pressure dropping when multiple [...]

  3. ajlovegrove says:

    Loving this and I am trying to do something similar, I am currently mucking about with POV code and byte masks etc, but would love to see your code if possible! Any chance of a sneek peek!

  4. Antonio says:

    Hi, congratulations for your project

    What is the number part of the electro-valves?

    Thanks

  5. [...] emailed in to show us how he has improved his bubble display since the last time we saw it. If you recall from last time, he was having issues with the air pressure dropping when multiple [...]

  6. Ed says:

    Love it. I’ve followed what you’ve been up to with your project, and love what you’ve been posting. Especially when you run into problems, and keep coming back to it!

    I haven’t even bought an Arduino and got it to blink … let alone get it to say hello to the world!

    But … would it be difficult for me to get up to scratch with it all, so as to get an interactive waterwall on the go? Laserjet quality bubble-printing might be just a bit too ambitious for a newb.like me…

    I was thinking of sensors and columns of bubbles, which visitors to a science house could then ‘activate’. Say ten columns, ten sensors. Probably all a little low tech for you – bubbles coupling up in holy matrimony to become one, or jolting down the line …. these are no problem for me.

    But, as someone new to this all, am I still biting of more than I can chew?

    Regardless: I’ve loved looking at the You-tube clips, and you’re a real inspiration. Keep at it, it’s looking fab!!

  7. [...] emailed in to show us how he has improved his bubble display since the last time we saw it. If you recall from last time, he was having issues with the air pressure dropping when multiple [...]

  8. Matt Richardson says:

    Hey Matt! I absolutely love this, and I’m not sure how I missed it until now. Regarding the issue with the curling vinyl tubes: have you considered using hard acrylic tubes instead? At Canal Plastic in NYC, they have many different sizes of acrylic tubing. It’s probably considerably more expensive than vinyl, but it may save you time and you may need less structural support. Anyway, nice work!

    • Matt Bell says:

      A few people have suggested acrylic tubes instead of vinyl. I need to check it out. It looks like I will be building a 64 column wide 8′ high one soon, and the prospect of straitening that much vinyl is daunting.

  9. [...] by a Jeep’s falling water display, Matt Bell created an Arduino-based bubble display, which turns Jeep’s idea on its head. Matt’s latest version makes a few key [...]

  10. [...] by a Jeep’s falling water display, Matt Bell created an Arduino-based bubble display, which turns Jeep’s idea on its head. Matt’s latest version makes a few key improvements that [...]

  11. [...] by a Jeep’s falling water display, Matt Bell created an Arduino-based bubble display, which turns Jeep’s idea on its head. Matt’s latest version makes a few key improvements that [...]

  12. [...] by a Jeep’s falling water display, Matt Bell created an Arduino-based bubble display, which turns Jeep’s idea on its head. Matt’s latest version makes a few key [...]

  13. [...] by a Jeep’s falling water display, Matt Bell created an Arduino-based bubble display, which turns Jeep’s idea on its head. Matt’s latest version makes a few key improvements that [...]

  14. [...] More about the build-instructions and inspiration can be read here and here. [...]

  15. [...] was also the bubble display built by Matt Bell. I only captured a short 240p clip of it, but it was very impressive. He uses mineral oil instead [...]

  16. [...] More about the build-instructions and inspiration can be read here and here. [...]

  17. I really like it when individuals get together and share views.
    Great site, stick with it!

  18. Cherie says:

    Great goods from you, man. I’ve understand your stuff previous to and you’re just too fantastic.

    I really like what you have acquired here, really like what you’re stating and the way in which you say it. You make it entertaining and you still care for to keep it wise. I cant wait to read far more from you. This is really a wonderful site.

  19. […] Bell has been working on a small bubble display and making steady progress improving it. His display uses solenoid operated valves to inject the bubbles, and his improved version uses […]

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 27 other followers

%d bloggers like this: