Hi everyone. For a project with the museum “Buddenbrookhaus” here in Lübeck, Germany, we were working together with five students, about 15 years old each, to create two exhibits for an exhibition. We, some guys from a local hacker- & makerspace were supporting these students to implement their great and crazy ideas. In the end, one of the exhibits involved 21 estimote stickers for an IoT suitcase. (I’ll try to make an English translation of our blog article describing the project in the next few days)
The first experience with the first box of ten estimote stickers was great, in that it was relatively easy to start and get going with the nodejs library “node-bleacon” on github, by Sandeep Mistry. Unfortunately, quickly we discovered, that out of these ten stickers, three ones were not working at all or only after some squishing… The Estimote support was very helpful to send us some replacement stickers very quickly, together with the second batch of ten stickers (as we needed at least twenty for the project).
That was in April. The exhibition opened at the 12th of June with finally everything up and running. Until then, the number of malfunctioning stickers had increased from three to five, we had to replace two more stickers about one week before the grant opening. So we ordered a third batch of ten stickers, just to have some stickers ready for any quick replacements.
Last week I got an email (24th of June), that one more sticker misbehaved. I went through the list of 21 stickers that should be there remotely and even found two of the 21 stickers gone. I came over to replace them today - and by that found out that from Friday until Tuesday, so just within four days, the number had increased from 2 out of 21 to 5 out of 21 not working anymore… Now I’m running out of replacement stickers…
The remaining stickers in the replacement box seem to have some issues, too: One of them beaconing at 100ms interval even though not in motion. One beacon sent gyro values x=0, y=0, z=0 once in motion, and only send correct values when still (battery starting to die, unable to power both the gyro chip and bluetooth at high rates, maybe?). Btw, I’ve never used the iPhone app or changed any beaconing intervals. I mostly used node-bleacon, sometimes the Linux “hcitool lescan” tool to check whether a sticker seemed to work and just a few times I checked with the Android app.
For the first batch with the three broken ones, we had opened up one of the stickers: It was clearly a hardware defect (will send a picture the next days): The hard solder blob of the battery holder had made two tiny but big enough rips into the flexible circuit board to create a loose connection.
For the others that died over time, it seems to me like the batteries are draining too quickly. Are there any known issues with a sticker firmware bug, resulting in getting locked to a 100ms interval? Or could it be possible that node-bleacon sends some messages to the stickers which might increase the battery usage?
Sorry for the quick write up, I’ll try to describe the project and setup more thoroughly the next days and ill try to gather more information, like the battery and beaconing values via the official Android app and will compare that to their actual behaviour.
If you have any recommendations what else we could/should check, then please let us know.
PS: The estimote stickers are mostly still. Only sometimes visitors are moving an object with an estimote sticker inside from a table into suitcase.
PPS: The Buddenbrookhaus had planned to lend the overall exhibition to other museums in Germany after this special finishes in January. But for the IoT suitcase, that won’t work out with the current issue of regularly broken estimote stickers and overall maintance work…
PPPS: We all love Estimote, the museum as well as the people from our hacker- & makerspace are totally hooked with the potential use cases of these and love to do more with them. And we are loving the availability of open source software for this hardware. So let us know how we can help to improve them, what to code & test, etc.