Badge parts and hub function

[Margaux]

Hi Oren and everyone,

I am considering using open badge (V3.0) to study team interactions in a group of 20ppl in an open environment and during several successive days (so lot of data!). And I have several questions, I should warn you that I have no background in electronics, I literally learned what a PCB is a few weeks ago, so some of my questions are probably very basic (and hopefully easy to respond to).

First, thank you for making all the information about the open badge available, I have found everything I wanted on the github, it's well organised and explained for a beginner like me!

About making the badges

1. I found the https://octopart.com/bom-tool/TAh4HILh created by Patrick that was cited in one of the GitHub discussions and 2 references are missing, I have found alternatives but are they a good match?
Num 8 - description: CAP CER 100UF 6.3V X5R 1206 - would the Murata GRM31CR60J107MEA8L work (https://octopart.com/grm31cr60j107mea8l-murata-111767348?r=sp#Specs)? It seems to present the same characteristics than the description, but I want to make sure I am not missing some crucial information!

Num 19 - description: RF TXRX MOD BLUETOOTH CHIP ANT - from what I understand it needs to be nRF51822 compatible, I looked on digikey would any of these ones be better than the others? https://www.digikey.fr/en/products/filter/modems-et-modules-d-%C3%A9metteurs-r%C3%A9cepteurs-rf/872?s=N4IgjCBcoJwBwBYqgMZQGYEMA2BnApgDQgD2UA2iAMxwAMA7GDCALrEAOALlCAMqcAnAJYA7AOYgAvsSZxm0EGkhY8RUhRC1Wk6SABMGgDqcABACUAGiYAqFyyYCyAeQAiJgEIAZAKoBRa05O1gASJgDCwQCSAAomvA4u2kA

2. Some elements are obsolete, how much should I worry about that? I don't really know what that implies in the case of the open badge. For example, the nRF51-DK still can be bought but has been discontinued by Nordisemi, but as long as I get parts that are compatible, it should work fine, right? In this case, I think I'll buy an extra nRF51-DK just in case! Or should I get another nRF (like the nRF52)?

About the study and hubs

3. The open environment implies that people will not necessarily always be close to a hub, or to each other. From what I understood the hub's main functions are to initialise and then periodically pull data from all badges that are synced with the hub. So would it be possible to have a hub per badge that each subject would always have close by to ensure sync and prevent data loss? And could it be a phone? If all the phones have an internet access, all badges will be time synced.  Would it be a good solution (1 hub/badge) or did I miss some specificities about the hub role?

Thank you so much for your help!

Margaux