# Feasability of an Arduino indoor positioning system using BLE

Our project is to guide a blind person in a known environment (here it's an exposition hall), and we need to have a precise way of figuring out where the user is. Our current solution is to use something like WPS, but with bluetooth beacons.

This is however our first project with Arduino, and we're not quite sure if we're going the right way about this. So far, we're thinking of getting a compass module , a bluetooth shield, and 3+ BLE beacons.

For the compass, I saw the HMC6352 but it's not sold anymore I think? Then for the shield, there's the WRL-13019? I think? I have no idea if that's even what I'm looking for. And I'm not quite sure where I can find BLE beacons either; I was thinking iBeacons should do the trick but they're a bit more expensive than I had planned...

So my question is: Can it be done this way, with a good enough accuracy (~1 meter), and with a low budget (~$100)? Additional information: The system is placed on the user, most probably strapped to the arm. The communication with the beacons will be done from there, as well as the calculations. The user will interact with the system through a 3-buttons pad placed on the cane. The environment is supposed to be as complex as an exposition hall, but we can aim higher, although the prototype tests will be held in a smaller room (~60m², I think). Budget range is around$100, Arduino itself excluded. A UNO is already provided to us.

Originally from Feasibility of a Wi-Fi Positioning System, but I figured Bluetooth might be a better idea (...right?).

## 1 Answer

getting 1 meter accuracy with bluetooth or wifi is very ambitious (especially for 100$). The signal strength behaves very erratic and this translates in large positioning errors. Perhaps if you keep your system in one big room (with the beacons up high and in line-of-sight) it may be possible. State of the art algorithms are between 1 and 3 meters and usually use some database with RSS fingerprints together with an IMU. As for beacons, I have used the Nordic beacons as they are very small and relatively cheap (around 30$ for a single beacon). However, they still require quite some programming in order to do positioning.

Alternatively, there is an Arduino project called pozyx about to go live on kickstarter that uses ultra-wideband for positioning. The ultra-wideband allows for very accurate distance measurements by measuring the time-of-flight (TOF) between two devices. Ultra-wideband is able to achieve an accuracy in the order of 10 centimeters. I think the full system (4 beacons and a shield) costs around 450\$.