[FTC]: Samantha? Like it or hate it?

[emmell]

Originally Posted by ssi

Actually, the Samantha holds TWO configurations at one time. It can know how to connect both to an FTC_FIELD and an FTC_PIT at the same time. That is why they did not have to load a separate configuration for each area.

Exactly right. David beat me to replying.

[wilsonmw04]

Just coming back form the Richmond Regional, I have to say that Samantha worked much better than the Bluetooth solution from last year. Matches all ran smoothly throughout the day. There were 4 communication issues my team encountered today. Twice, our NXT froze in the middle of matches after sustaining a shock during normal game play. Samantha stayed connected on both occasions. Second, one of our alliance partners lost communications with the field. The cause of the disconnection was a poor power connection. The last was a miscommunication with the field staff about which controller set my team was using during an elimination round. None of these were do to the Samantha module.

[Andrew Schuetze]

the later posts in this thread seem to validate that the Samantha unit is working but we do need to learn what causes large scale crashes to improve on the best practices for tournament organizers and team behaviors. I think the post by emmell is a must read at this point for everyone either competing in or running FTC events.

[JesseK]

I don't think the posts in this thread are indicative of a 'lack' of problems that were experienced.

1.) The FTC organizers need to send out something official to all of the teams in TIMS about best practices in mounting the modules. Go to an FTC event and ask around about ChiefDelphi ... very few (rarely ever a first-year team) have heard of the website.
2.) Telling students their battery voltage dipped during the match (which is why the module dropped out), yet not allowing the students to see how bad the drop was (length of time, amount) in order to determine whether or not to return a brand new 13.7V battery back to the mfr. is not the way an FTA MVP should treat people he wants to sustain within his program long term
3.) If we're expected to have proper battery voltage meters, SEND IT OUT IN AN OFFICIAL UPDATE. As 'smart' as the mentors are, we are incredibly dumb about the many things we can't even fathom postulating, let alone knowing we need the something. (The flip side it true as well)
4.) Fact: if we ever change communications modules again in FTC, we will forgo the FTC program. Sure the 4 teams we have are nobodys, but we've gone through this exact experience twice now. A robot sitting still on the field doing nothing is not a way to 'Celebrate' the accomplishments of the students. We are tired of being an 'experiment' for the lowest bidder. It is very obvious the Samantha modules were not shock tested one bit. Even with a proper USB attachment to the frame, I could thump the thing and reset it.

[emmell]

I just want to make some suggestions about the previous post:

Originally Posted by JesseK

1.) The FTC organizers need to send out something official to all of the teams in TIMS about best practices in mounting the modules. Go to an FTC event and ask around about ChiefDelphi ... very few (rarely ever a first-year team) have heard of the website.

I beg to differ. FTC has sent out something official. Read all of the Team Email blasts that have been sent. The blast on 11/18 had a link for a white paper with a diagram of how best to mount the Samantha module. You can find the email blasts here: http://www.usfirst.org/roboticsprogr....aspx?id=18132

Originally Posted by JesseK

2.) Telling students their battery voltage dipped during the match (which is why the module dropped out), yet not allowing the students to see how bad the drop was (length of time, amount) in order to determine whether or not to return a brand new 13.7V battery back to the mfr. is not the way an FTA MVP should treat people he wants to sustain within his program long term
3.) If we're expected to have proper battery voltage meters, SEND IT OUT IN AN OFFICIAL UPDATE. As 'smart' as the mentors are, we are incredibly dumb about the many things we can't even fathom postulating, let alone knowing we need the something. (The flip side it true as well)

I won't comment on what the FTA told you at your event, however you don't need a voltage meter at a competition. Your NXT will tell you what your battery levels are and so will the FCS if you are running it with the FTC_PIT configuration. If your NXT is >7.5 volts, then you're good. Anything less than 7.0 volts will probably not work well. For your TETRIX battery, anything greater than 11.0 volts is good and < 9.0 volts will not run. The FCS will light with Red, Yellow, and Green in the team box for these conditions. This is documented in the FCS manual.

I won't comment on the 4th item. Just pointing out the facts. The key for all the mentors and teams out there - READ EVERYTHING THAT YOU GET. It's important information and will help you be better prepared for your next event.

Good luck teams!

[PSHRobotics]

The biggest problem I personally found in how the regional in St. Louis occurred was the determination if a match should replayed. This is nothing against the referees as they were forced to make decisions on the spot in order to make sure the competition continued to run smoothly. This, I feel, is more a problem of the rules.
The referees decided to only replay one match throughout the day. The reasoning for replaying this match was because the referees felt that there had been a "significant" impact to the outcome of the round. The rules need to be rewritten to account for factors such as this to avoid confusion and make it easier for the referees. There were many tempers that were ignited because of this specific round being replayed, while others had not been replayed - a rule would redirect anger away from referees who already have other frustrations pointed in their direction.

[l0jec]

Originally Posted by PSHRobotics

The reasoning for replaying this match was because the referees felt that there had been a "significant" impact to the outcome of the round.

I beleive the reasoning was because that signifigant impact to the match was determined by the FTA to be a direct result of the field. The other matches which were not replayed were not determined to be caused by a field fault.
Of course we can argue all day whether certain communication issues where because of the field control system or because of individual issues such as loose wiring on samathas, but and the end of the day, I think the refs and FTAs already make their decisions as best they can based on what they have available to them in a fair manner.
Perhaps there simply needs to be better communication to teams when such decisions are made?

[EthanMiller]

New information from an informant at Clarkson shows that some of the problems may have resulted from poor setup on Clarkson's part - I don't know the details of it, but it sounds like not quite everything was set up right and/or tested realistically.

[Random Dude]

In terms of router naming, one issue I ran into when running a scrimmage out in Oregon, was the school I was at already had a router named "FTC_FIELD", which I didn't know at the time. I think it got turned on part way through the morning, and I suddenly had 1/2 my teams complaining they couldn't connect.
Once I tracked that down, I decided to put custom names on all my competition routers. That way if someone accidentally turns on a FTC_FIELD router at a competition, my network won't collapse. I also plan on running around with a WiFi scanner and disabling any rogue access points.

[Madison]

Originally Posted by Random Dude

In terms of router naming, one issue I ran into when running a scrimmage out in Oregon, was the school I was at already had a router named "FTC_FIELD", which I didn't know at the time. I think it got turned on part way through the morning, and I suddenly had 1/2 my teams complaining they couldn't connect.
Once I tracked that down, I decided to put custom names on all my competition routers. That way if someone accidentally turns on a FTC_FIELD router at a competition, my network won't collapse. I also plan on running around with a WiFi scanner and disabling any rogue access points.

My understanding has been that the FCS connects to FTC_FIELD by default whenever it is present. It only looks for and connects to the secondary SSIDs when there is not an FTC_FIELD present.

We've competed up here for the last two weeks. The first event was late in getting started because of interference from routers running their own FTC_FIELD. After that problem was weeded out, the event ran smoothly, for the most part.

This weekend, there were fewer problems with conflicting network names, though we did have some trouble with persistent intermittent connection loss -- if that makes sense -- and it resulted in some pretty terrible consequences to teams and robots. The folks running things were great about troubleshooting it and rerunning matches as necessary, but it still meant that several robots broke or were broken because of our inability to properly control the robots.

The wifi system operates better than the bluetooth system, but I wouldn't go so far as to call it a good system.

[Random Dude]

Originally Posted by Madison

My understanding has been that the FCS connects to FTC_FIELD by default whenever it is present. It only looks for and connects to the secondary SSIDs when there is not an FTC_FIELD present.

We've competed up here for the last two weeks. The first event was late in getting started because of interference from routers running their own FTC_FIELD. After that problem was weeded out, the event ran smoothly, for the most part.

<SNIP>

The wifi system operates better than the bluetooth system, but I wouldn't go so far as to call it a good system.

The behavior was actually changed in a newer version of the firmware (which should have been installed at your competition). Samantha has two network configs stored in it (typically FTC_FIELD and FTC_PIT, but can be anything). It will toggle between then approximately every 6 seconds, until a FCS attempts to connect to it, and then it will remain on that network until power is cycled.


I'll consider it good if I can get through my 7 tournaments without having to babysit the connections of every single match. (Because, it sure felt like I had to do that with bluetooth last year)

[JesseK]

Originally Posted by Random Dude

I'll consider it good if I can get through my 7 tournaments without having to babysit the connections of every single match. (Because, it sure felt like I had to do that with bluetooth last year)

The only thing I'll say that's definitely positive about the Samantha module is the fact that we no longer have to lug a laptop and controller pair around. Our teams (at least) understood the nuances of bluetooth enough to remove all connection issues (usually reset the stack on the laptop and then reset the brick every 5-6 matches). We only shut off once throughout all of last year, and video revealed that was because another robot's outer mechanism went into our robot and wound up hitting a button on the NXT. If we could at least figure out what's going on with the Samantha, the kids really wouldn't care if they had to babysit it again ...

I would like to thank the feedback in this thread that points out helpful tips -- these things will definitely be passed on since often times other teams I've met barely have the capacity to program the thing to begin with let alone read every email, blog, and forum thread on the subject. We'll see how things go at the next qualifier in January.

[Shadowfl]

I honestly can't say much about this question because it is my rookie year in FTC. but from what i know from technological evolution i conclude that the Samantha system does its job pretty well for its first year of mainstream FTC competitions.

[aklego]

I just FTA'ed at a small regional and we had two of the problems mentioned here: Signal drops and NXT lock ups.

Excepting the occasional loose wire, the signal drops were caused by low 12v batteries. However, I'm reluctant to blame that on the teams. The FCS uses essentially open circuit voltage to determine the state of charge. That is problematic, as a moderately discharged battery can still show green. Then, as soon as a load is applied, the voltage drops below the Samantha minimum and the module resets. We were fortunate in that our tournament had a 3-hr built in break. During this time, all the teams fully charged their batteries and the problem vanished. Teams that did all their practice and testing using tethering or bluetooth would never see this issue until their tournament. And teams that use many heavily loaded dc motors will be much more vulnerable to dropouts.

An inelegant fix for next season is to run samantha off of an independent battery.

NXT lock ups were the other issue. The only pattern I saw was that some robots never had the problem; the robots that did, however, had it repeatedly (but not consistently).

[Random Dude]

That pretty much mirrors what I've been seeing in Oregon in the 4 tournaments we've had so far. We've only had 1 NXT lock up, but Samantha losing power happened with some regularity. I definitely agree with the weak vs strong battery data.

As much as I don't like having another battery, I'm tempted to suggest to FIRST that Samantha have it's own. (I may also experiment with some of my local teams during the off season). The other thing I think will help would be splicing samantha directly into the battery connector, instead of way out at the end of the motor chain.