Event Partner thoughts for Teams and Other Event Partners

Our 4-H robotics club just hosted the Second Northwest Maryland VEX Robotics competition in Westminster, Maryland on Oct 31. Here are some things we noticed this year that may be helpful to other event partners and teams:

To start, we ran a combination VEXNet/crystal event. All teams were encouraged to use VEXNet, and teams who chose to run crystals did so at their own risk We would not accept complaints about interference and bad crystals. From an event organizer perspective VEXNet is great! From a coach perspective, VEXNet is still a little frustrating. It seems solid once you get everything working properly. Teams transitioning to VEXNet, buy the $19.99 VEXNet Competition Switch and test, test, test…. I believe in the end VEXNet will improve the quality of events. But don’t expect to place VEXNet on your robot and head to your next competition without thorough testing of your code and robot.

Template problems- We had many teams show up with old versions of the Easy C and Robot C templates in use. When I say old, I do not mean last year, but rather, versions that were downloaded a month or two ago. The developers of both Easy C and Robot C have been releasing new updates (templates, master code and software updates) fairly regularly. All teams should look on the appropriate website for their programming environment a day or two before their upcoming competitions to make sure they are running the most up to date versions of programming software (Easy C or Robot C), Master Code, and competition templates. While we delayed our start to try to ensure teams would run on the field, some spent several hours solving their software problems and they kissed some matches. Teams running VEXNet seemed to be most vulnerable to the issues associated with old templates and software. As I said above, buy the switch and test thoroughly! … and when I say test, drive your robot and make it work hard as you would in competition.

VEXNet Backup Batteries- We had teams without VEXNet backup batteries. If yours was backordered, I understand IFI (VEX) now has them in stock. But IFI seems to have forgot to ship to the teams who did not receive them with their VEXNet upgrades. In another post I saw where IFI is asking that teams contact them with their VEXNet order number and they will ensure you receive your backordered battery holders and cable. When running without the backup battery, it appeared that excessive current draw resulting in a battery brown-out would reset the radio link, and when controlled by the field VEXNet did not always re-establish the link once lost.

New VEXNet Field Controllers- We had some challenges getting MS Windows to install the field controller driver correctly. But once we overcame this issue, the field controllers worked very well. This is an issue we have experienced in the past with old field controllers as well. The addition of the LEDS showing disabled, autonomous and driver modes on the new field electronics are wonderful. Unfortunately, we found all the LEDS on the VEXNet backpack rather confusing . Each field manager and ref really needs guide to compare colors and blink rates to figure what’s going on with a robot that did not run.

Scoring- Congratulations to IFI for a great game, but scoring is a challenge until the refs get the hang of things. We had a couple mistakes at the start where refs reversed the Blue and Red scores because of the position of the teams is opposite of the scoring zones.

Field Reset and Match Schedule- We were able to run six minute match spacing quite comfortably once we got everything flowing properly. We alternated between 2 fields. Expect the first 4 to 6 matches to go somewhat slower due to the Refs figuring out the scoring and the field reset volunteers getting up to speed. Very ambitious event organizers could probably shorten the match spacing to 5 minutes or maybe even 4.5 minutes.

Entanglement- We had a number of instances of entanglement where teams were trying to dump over the wall and a team on the other side was blocking. Some instances were cleared quickly, but a couple bordered on entanglement with intent to hold and disable an opponent. Warnings were given by the Refs, but I believe we had no disqualifications. Teams need to be careful with their designs to ensure they cannot be held responsible for entanglement.

Tournament Manager Software- IFI has done an excellent job adding features to Tournament Manager that helps with running of the event and provides more information to teams and the field operators.

Robot Sizing- Teams, be careful with your robot size. The rules this year do not allow touching of the sizing box. We had a couple teams who came with designs that needed to be crammed into the box and had zip ties and more rigid items touching the slightly generous sizing box that we used. The box cannot be supporting or touching any part of your robot. If you do not have a sizing box, a couple 24” framing squares (available at most any hardware store) and a tape measure will help you determine your actual size. If you are pushing the size limits, don’t just eyeball it assume you will be ok. Fixing your robot size as the competition starts without you is no fun! Oh, and your flag must fit within the box as well, without touching. Though I do have another comment on flags below.

Flags- Are they really needed this year? There is no mixing of the Red and Blue alliance robots, and I am all for eliminating any item that is not needed. Even the smallest item, like the occasional missing flag that must be found and installed can slow down an event.

Anyway, enough of my rambling. Hopefully someone finds some of this info helpful.

Thank you for taking the time to write this. It is great advice, and our first tournament of the year is this Saturday.

We bought the switch but it did not tell us that we would not be able to run the Robot Skills competition, which was a big disappointment to us.

Again, we bought the switch and had the latest RobotC code and templates but we didn’t know we would not be able to run the Robot Skills competition.

These batteries are called backup, but ours seems to go dead in a couple hours. What exactly are these supposed to do and how do you keep them from going dead?

The other thing that we noted is that a number of teams that showed up with VEXnet abandoned it and went to crystals. We stayed with it but had a number of issues at the competition that we didn’t have at home, such as:

  1. our code was corrupted after each run on the field and we had to re downloaded after each run. We didn’t move on the first match even though we came straight from the software testing station and ran just fine there.

  2. We were not able to download wirelessly at the competition. We had to unplug VEXnet and plug the orange programming cable directly into the microprocessor.

So again, I don’t think the competition switch does a good job of emulating the field control software.

Sorry if this is the wrong place to post this and I don’t mean to complain. This was just our experience. The event was fantastic and we had a blast. It was very well run.

very nice experience sharing
i have a question though
my team has the crystals (no more budget for vexnet :()
and they are using last years elevation template
they are doing so because it already has a 20 second autonomous and a driver control
will there be any clash between the two transmition type/template type?
thanks

You should ensure that both your development toolkit (RobotC, EasyC, MPLab, or other) and the template that you use are in synch so that mismatches don’t cause problems.

And, you should avoid known, already-fixed problems that exist in some versions of those toolkits.

You should download the latest version (at no cost) of whatever toolkit you are using and should use the template that comes with that latest version. This is one thing Dave was emphasizing.

For example, you should not download and use a new release of EasyC, but continue to use an old template from last year (or vice versa).

Separately, your software’s/robot’s interaction with the field will not be affected in the slightest by the control method other robots use. However, during the match, the crystal-based communication method can be degraded by ambient noise or by other crystal users’ signals. This is nothing new and is not related to the software.

Blake

**If you are using Crystals, the safe thing to do is use the same programming software/templates that worked for you last year. The time for the matches has not changed.

ROBOTC will be releasing a new version of the software to fix some of the above issues. Always use the latest version available (easyC or ROBOTC) for VEXnet operation.

ROBOTC software would not enable Driver Mode unless Autonomous was run first. Therefore, you most likely could have used the VEXnet Competition Switch for Skills testing but you would have had to start with the VEXnet Competition Switch set to Disable and Autonomous. To start the Skills Robot Test you would select Enable on the VEXnet Competition Switch, and then select Driver Mode. This sequence allows the Autonomous Mode to be active a very short time – the time from Enabling to selecting Driver.

To obtain maximum battery life, you should disconnect the Backup Battery after your match is over and reconnect it before the beginning of your next match. The Backup Battery will keep the VEXnet running should you lose main power. If the team is just practicing, etc., you do not need to have the backup battery connected. It is only really necessary during an actual match when it is absolutely critical that your VEXnet pair not lose power – time will be wasted if the system needs to re-link.**

I helped out at the NW MD Vex Robotics Competition. We found that several teams using crystals had to use the newest version of EasyC with the built in templates. They experienced issues switching from operator control to autonomous on the field. Simply updating the master code did not correct the problem. After installing the EasyC update and cutting and pasting their code into a new file (created from the built in template) they were able to run successfully. If you are running crystals, I would strongly recommend updating both EasyC and your master code.