Bluetooth at competitions
 

Hello all,
Some other students and I on my team are currently working on designing an electronic scouting system to replace our old paper-based one. Originally, we were going to use a flash drive connected to our Android tablets via and OTG cable, but that plan fell through because Android does not seem to support hot-swappable external storage. We are currently exploring our other options; Bluetooth seems to be one of them. Can anyone confirm once and for all whether or not Bluetooth is allowed at competitions? I've seen conflicting information on this site and want to be totally clear on what is and isn't allowed at competitions.

Re: Bluetooth at competitions
 

I suggest asking Big Al at your next meeting.

His answer, like mine, will be NOT official, and therefore NOT once and for all. His might carry a little more weight than mine, though, partly because he's the Chief Inspector, and thus a little more versed in the intricacies of the rules than I am.



Now, unofficially, I can't find anything in the 2014 Administrative Manual that would by itself prevent a bluetooth network, or any other type of network, wired or wireless, provided that it does not connect to the Internet or attempt to do so (Section 4.15). Not having seen the 2014 Game Manual, I can't comment on what may or may not be in there regarding wireless networking and use thereof.

Re: Bluetooth at competitions
 

I think there's several sources of conflicting information. Lets first start by looking at the relevant rules (from 2013, you will need to verify with the 2014 rules).

Bluetooth is illegal to use on the driver station, so make sure your driver station doesn't connect to your scouting system. However, this rule does not ban Bluetooth in general.

Some people mistakenly believe that Bluetooth is part of 802.11. Bluetooth is 802.15, rather then 802.11, thus is not banned by that part of the rule. Other people believe that since Bluetooth uses 2.4 ghz, it is banned by the parenthetical. However, I (and most people) believe that the parenthetical provides clarification that both frequencies of 802.11 are banned, and not that 2.4ghz in general is banned.

The second issue is that there have been a few anecdotes of Bluetooth being disallowed in the middle of competition. On the other hand, there are many anecdotes of teams successfully using Bluetooth at competitions. One anecdote specifically mentioned possible interference with FTC at the championship. Considering that running a successful competition is more important then your team's scouting efforts, you should have a backup plan if there is interference and an event asks you to turn off bluetooth. In the past, where different venues have had different interpretations of rules, often asking a question in the Q/A will help to provide an consistent interpretation.

You may want to ask your teammate why he thinks bluetooth is banned. http://www.chiefdelphi.com/forums/sh...1&postcount=15

Re: Bluetooth at competitions
 

Thanks to both of you for your quick replies. I'll talk to Al at kickoff this Saturday (Speaking of kickoff, I can't wait! :D ) and see what he has to say. Both of your replies line up with what I've seen in the past (not explicitly forbidden, but anecdotally it has been disallowed during competition). As for my teammate, I'm not sure with what authority he says that. I'll check with him later, as he sounded pretty definitive.

On a side note, I did find a workaround for the flash drive issue discussed in the original post. If any teams reading this in the future run into a similar issue, contact me and I can help you out.

Re: Bluetooth at competitions
 

Just be sure you check CD every day for the next 15-20 years, because that's how long your post will likely be visible and relevant here on CD.

Or just write it up and post it as a whitepaper, so anyone in the future has their answer, immediately. Maybe?

Re: Bluetooth at competitions
 

"Who were you, nathanwalters? What did you see?!" (http://xkcd.com/979/)

Re: Bluetooth at competitions
 

Speaking to the issue with FTC, the new FTC controls system does not use bluetooth (Thankfully), so that should not be an issue.

Re: Bluetooth at competitions
 

Thank you Wren, that's good to know.

I fully intend on writing up a whitepaper once development of our system is complete, both as a resource for anyone looking to build their own scouting system as well as a resource for future members of my own team so they know how to maintain the system. Who knows, we could even open-souece the code! That last post was simply a stopgap solution until my teammates and I can finish the system and write up a whitepaper.

Re: Bluetooth at competitions
 

What tablets were you planning on using? I have a rooted nexus 7 (2012), which does allow hot-swap, but only if you root it first, and install an app designed to allow you to access the external storage. There are quite a few of them on Play.

Re: Bluetooth at competitions
 

We might want to move this discussion off into another thread about scouting tablets (as if there weren't already enough!) so we can keep the focus of this thread on Bluetooth.

Re: Bluetooth at competitions
 

I'm not sure what version of Android you're using, but I can hot swap flash and SD storage on my phone (HTC One, Android 4.3) with an OTG cable using the ES File Explorer.

Re: Bluetooth at competitions
 

I'm running a CyanogenMod 10.1 nightly build on a Motorola Xoom. Some file explorers may be able to support that; that's not really of any concern to me as I need to do all writing to the drive programmatically from my app. The problem was that the contents of the files I was writing to were not successfully being written out to the external storage if I didn't first unmount the drive from Settings->Storage->Unmount USB storage. It appears that the Android system buffers some external storage file operations, and those buffers aren't synced to the physical device until it is properly unmounted; at least, that's the only explanation I can think of for the behavior I was seeing. This problem was called by executing the shell command "sync; sync" immediately after writing my data to the flash drive. Thank God for SuperSU!

So much for waiting to write up a full explanation :P

Re: Bluetooth at competitions
 

I believe BT is allowed at competitions. However, keep the communications limited because there is the possibility that it will cause interference, because it operates at the same frequency.

How do you create a bt pan with a bt-enabled laptop act as the router? That would allow me to run servers directly on the laptop instead of the other side of the world (sarcastically). :confused:

Re: Bluetooth at competitions
 

3138 used 4G tablets standalone last year at Queen City and Championship.
4G USB adapter -> router -> ethernet switch -> USB ethernet adapter -> OTG cable -> tablet at Crossroads and IRI (trust me, it's as bad as it sounds). Even though ethernet wiring was a complete PITA, it was quite reliable, and broke no rules. Though do yourself a favor and go with an OTG adapter that has both a power plug and an ethernet adapter, and not a generic OTG->USB-A adapter.

4G radios on their own is of course optimal if that's an investment your team can make - it's just not always working well at venues (see: Crossroads).

BT PAN was flaky when we tested it, but we're looking into it again this year. Who knows.

Just my $0.02, given IPA gave us quite the crash course in this type of thing last season.

Re: Bluetooth at competitions
 

There have been other scouting systems in past years that have used bluetooth, and I would assume they haven't added a rule about it (which I don't see why they would, nor do I remember reading that there was in the manual.). Ho from what I understand it takes some effort to set up and even so, I've heard scouting with bluetooth can be glitchy.