Positioning Visitors with iBeacons

When Apple released iOS7 in 2013 one of the new features introduced was iBeacon. This technology would now enable Apple devices to pick up broadcasting signals at short distances from pieces of hardware called Beacons. Theoretically beacons can be used for all sorts of things including and most importantly for us, indoor positioning. We want to use iBeacon technology in the ASK app to give location information about the visitor as they ask a question. If we know what gallery the visitor is in—and even better, where in that gallery they are—we’ll be able to better answer their question. To achieve this we placed beacon hardware in the galleries so that when a visitor asks a question the app detects the closest beacon; the visitor’s location is then transmitted to our audience engagement team who will answer queries.  Each beacon has location information assigned to it so we know where the visitor is in the museum. We initially chose two beacon vendors to begin our beacon testing:  Estimote and Kontakt. Both are big players in the newly founded beacon vendor world. And so we set out ordering a handful of each and began our tests.

The first round of testing ended with disappointing results. We experienced very erratic results…very, very erratic. We could be standing right on top of a beacon and it wouldn’t be detected—although strangely, it might detect the beacon on the other side of the room.

With test one behind us we started to look a little deeper and do our research into what was going on. Beacon technology wasn’t going to be as plug and play as we’d hoped. We referred to endless blog posts of experience working with beacons.  Stephen Elliott founder of Llama Digital had written an insightful post on beacon positioning for best detection results.  The article suggests using brackets to mount beacons in such a way as to achieve optimal signal strength. Because of the gallery layouts and general architecture we aren’t able to follow this approach so onward we went. We spoke with Jess Elder and Scott Newman over at the National Geographic Society. They’d recently added beacons into one of their installations. They found mounting beacons on the ceiling gave them more accurate results. Although they also cited similar frustrations with inconsistent beacon detection. Placing beacons on the ceiling wasn’t an option for us either—in many cases our ceilings are incredibly high and getting lifts through the galleries for placement, testing, and battery changing was not going to be practical over the short or long haul.

We performed various other tests, including changing power settings on the beacon which would in theory make the signal weaker or stronger. We tried adding and removing beacons in a room. None of these tests were giving us the consistency we’d hoped for. One gleaming limitation is of course the technology used to transmit beacons—Bluetooth low energy technology. Bluetooth technology is based on radio waves. Radio waves are inherently flaky because of interference. In our case interference might mean any work of art, vitrine, installation partitions, or even other visitors in the gallery! Ultimately each gallery has its fair share of radio wave blockers.


In the end we found that basic detection was not enough and so the app works a little harder to determine which beacon is the truly closest one. This involves caching beacon results and time of detection as well as using the accuracy metric from the Apple Core Location API. This metric gives the number of meters the Apple device is from the beacon…in theory.  The accuracy measure is at times wildly inaccurate but tracking that measure and averaging results helps give a more ‘accurate’ result. Beacon placement was very important to make sure we were getting decent coverage in the space we were attempting to identify. We placed the beacons roughly 7-8 feet high and 15-20 feet apart in each gallery. Having the beacons sit higher on the walls works well to remove the beacon from the general range of vision.

One thing we were certain on was that Estimote and Kontakt were both decent beacon vendors. We ultimately chose Estimote because we’d found their developer community to be sizable and very active. The Estimote forums discuss issues which Estimote then fix in a relatively timely manner. The SDK has had various releases as has the firmware. These releases have addressed some big improvements in battery life and security around the beacon.

estimote beacons
estimote beacons

Of course the one big difference between the two beacons is the look. At the museum the aesthetics of each gallery are very important. A great deal of time is spent designing the galleries and adding beacons throughout was a sticking point for some. The Estimote beacons come in a limited number of colors and have a distinctive look. As a starting point we’ve chosen the least intrusive color ‘Icy Marshmallow’ and we are eagerly awaiting more color options which we understand are coming by the first quarter of 2015.  The decision around placement of the beacons has been informed both by accuracy and detection for our app as well as minimizing intrusiveness in the gallery as much as we can allow.

Adhesive was also a concern as objects in galleries are often changed and so might the beacon placement. We had to be sure the adhesive wouldn’t damage the wall and would be easily transferable to the next location. In most cases Estimote beacon adhesive seemed to work ok with several exceptions where we’ve doubled up with Scotch Removable Mounting Squares.

So all in all, it’s been a fantastic learning experience for our team—not only working with new technology and evolving software and hardware SDKs, but also how they can best interact and co-inhabit a delicate environment like the traditional museum gallery space. This is only one of many ways we are trying to merge the physical and digital experience, and look for a simple, elegant application of technology that is invisible to the visitor, yet enhances the experience.

What’s next for us? Our Beta test of the ASK app will be happening soon. We are hopeful this will reveal more insights into iBeacon technology and its best application for us.