Lab Post : Signal Flare
6
December
2014

Dealing with led balloons are harder then it seems

When we started playing with led’s we had two things in mind, led as light source and interacting with multiple light sources according to an input. So as a light source it is occasionally okay to see the source itself naked eye specially when talking about strips. Diffusing it with frosted materials way to go. But when it comes to balloons you realize you have to choose either wired connection with impossible knots or closed connection with battery for a limited time.

With this in mind we looked for the best cheapest balloons. Only option we found is Latex which can be inflated around 1.5 meters diameter. It is good in size and price ($10/each) but obviously it is easy to blow up. The next best balloon we found is made of PVC, it is definitely much more durable and functional nad way more expensive. It has to be sewed and sealed. That is the production material but for now we have to stay in the budget.

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As we were just looking for simple solutions, deflating the balloon everytime we need to update the code on Arduino wasn’t that convenient. Even we placed a radio transmitter, battery fact was there. Wired connection is hard depending on the led’s in use. Some of them has 6 pins which makes it just a mess. Because you have to get the led inside the balloon with some cables and return with the same amount of cables to the next balloon as it multiplies by two.

So we tried three or four different chips and decided on WS2811 because of the 3 pin connectivity and libraries. But after sometime we experienced some technical issues with the WS2811. We couldn’t figure out why but sometimes the first led burns and so the rest of the strip loses the connection. After a while as updated version WS2812B was released. We have been using it so far and no problems with it.

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We were looking for input options to change the colors in balloons. We tried tilt sensors inside to react a push or a kick but it was insufficent. The more collision point moves away from the sensor the less feedback you get. Tilt sensor is still may be the best and cheap to use but there was multiple variables that could affect it’s stability so we turned to accelerometers.

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After a while we wanted to just disconnect the balloon from usb port of the computer which was feeding the power it needs. We found a Sony portable battery and wrapped it with Arduino Micro with the software compiled into it and an accelerometer. Results were more than great. Next thing would be to get a well housed balloon produced for more stable and durable testings.