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Discussion: Applying time offsets to controls

in: Orienteering; General

Jun 3, 2024 1:14 AM # 
I'm writing up some guidelines on synchronising SI boxes (and fixing problems arising from unsynchronised SI boxes). I'm trying to make it applicable to the event management software used in Australia (MeOS, OE10, OE12, and SITiming), and would be grateful for advice on how time offsets are applied in MeOS and the OE variants.
Jun 3, 2024 2:15 AM # 
I just had to do this in MeOS, it was straight-forward and these instructions from their documentation apply to all controls, not just start/finish.

From the Controls tab, select the control you need to adjust and enter the adjustment into the "Time adjustment" box, then click Save.

The time adjustment value is saved, so you can always see what adjustments are being made/undo them or adjust them easily.
Jun 5, 2024 4:53 PM # 
By using SI BSF8 "SI Master"/"Time-Master" station, it takes less than 20 minutes to clear the logg memory and sync about 100 base stations with a resonable procedure. By doing so a day or two before the event, my exerience is that they will diff less than a second during the event (which is enough for us). So far I have not had any need to add a time offset in MEOS. But naturally misstakes can happen. And with significantly more units, this might be a challange. My point is simply that with an SI Master unit , we don´t see the "sync part" as an issue. More challange is to be sure all units are correctly configured. It is easy to do misstakes when you have to reconfigure a significant amount of units, even if you check afterwards.
Jun 5, 2024 6:52 PM # 
The most important piece is making sure the finish unit(s) and start unit(s) / results system for timed starts are fully synched. If a control on course is out be a little bit it doesn't affect the official results.

Synch everything a week or so before the race. The morning of or night before resynch the start and finish punches with the Time-Master station after ensuring the Time-Master station and results computer system are synched. At least for championship races.
Jun 5, 2024 7:14 PM # 
Maybe off topic, but has anyone looked into the timming sync issue in the emit system?
As I understand the time is kept by the piece carried by the runner... Is there a possibility of variation between 2 emit cards in the timming accuracy? And is there a risk of technical cheat where the runner would use a modified card with a slower clock resulting in a faster race time?

Emit has been used for at least 30years so I guess this must have been figured out by now...
Jun 5, 2024 8:18 PM # 
What does that mean Canadian "after ensuring the Time-Master station and results computer system are synched".
At Suncoast Orienteering we zealously sync all the BSF-8 stations every time about two days, perhaps three before the competition, making sure to use the EXT Master setting so all old information is erased from the BSF 8s.
We use a BSF 7 station for download to a computer running the Irish Or timing system but it could be MEOS or any other timing system. What does it mean ensuring those two are synched? I don't think we have ever consciously done that.
Jun 5, 2024 8:20 PM # 
The variation between two cards should be quite good, I think on the order of one second per day, so less than a second for any race. A card with a slower clock could be built, I'd think, but it at least used to be the rule that the electronic punching system was supposed to be separate from the overall timing system, at least for high-profile events. Has that changed, and if not, is that policy actually followed?

(If you want to hack electronics, there are other approaches, but I don't of any cases of it happening as of yet.)
Jun 5, 2024 11:23 PM # 
Related to intentionally cheat: If not your start time, finish time and also a separate check that you visit every checkpoint in correct order are monitored externally, I assume it is possibel to cheat with whatever punching system that is used. At least it would be rather easy to cheat also with the SI system. But why should you? Orienteering is in a rather high degree based upon fairness between competitors.

Related to sync SI units and the MEOS computer: I can´t see a strong reason to do that, even if it is a good practice to sync the computer to an atomic clock via internet, and then set the time of the SI master from that computer. What might be more important is to sync the start clock with the SI units, if fixed start time is used. That said, if just one start clock is used, a potential diff would mean same time error for everyone.
Jun 5, 2024 11:28 PM # 
EricB, Gord,

The potential reason for it being important is that if by default participants are running on a timed start without a start punch but someone say a volunteer with the start crew that is starting late uses a start punch then the volunteer's start time is based on the start unit synched to the time master but the other participant's start time are based on the time in the results software/computer. They are unlikely to be off by much but still they could be off by enough to effect a placing or two in a tight race.
Jun 6, 2024 12:07 AM # 
But for a timed start I assume you need a start clock, synced with the SI units as I wrote above? Sorry, not sure I see the connection to the computers clock itself, as long as you don´t use the computer screen as the start clock. For a timed start, MEOS just subtract the start time (from a start list) from the finish time (from the SI pin) when calculate the actual time. The computer clock itself is not used what I know. But we might have different start set-up, and if so I am eager to understand yours!
Jun 6, 2024 6:49 AM # 
@rphlo Emit brick has internal clock, but there is no need or way to set it right. For races It is used only for elapsed time between controls. And it is used only for split times. For trainings it is used also for result.

Race result is based on your start time (from start list) and finish time (laptop's clock, there is online control at finish line). So if your brick's clock runs too slow, you'll get very poor time to #1 and fast splits then on.

With Emit we never need to program any units or set times or verify those tasks anyhow. And that also means no human errors when programming or setting times. That has saved huge amount volunteer work during past decades and makes it possible to have this many events (about 3000..4000 events every year with emit). That is the main reason switching system to something new has not been a realistic idea, we simply can't switch to a system that requires a tad more volunteer work, especially the kind if volunteer work that requires skills like programming and ability to be meticulous. But I don't now how much other systems has improved, but this disscussion makes me believe there hasn't been enough improvements.
Jun 6, 2024 9:26 AM # 
@Jagge: Don´t see a big difference with Emit and SI from that aspect: For the final result, the important thing is that the start clock and the finish station are in sync, also for SI. The rest of the "sync" discussion above is just to get correct split times (for everyone, for all split times, so it can be compared). If that is not important, you don't have to sync anything else. For SI, there are possibilities to change things like control number, touch-free on or off and so on. Since it is possible to change, some people do it to optimize for a race. If it is good or bad to have this configuration options can be discussed, and in some clubs it is forbidden to chance it for the reason you are into. Many people like the system they are using (me included). Why consider to change if it works ok for you? A change itself will probably be cumbersome for both the organisation and for the participants.
Jun 6, 2024 1:37 PM # 
@EricB. Yep my bad.
Jun 6, 2024 1:41 PM # 
From SI Config+ User Guide: Time synchronisation with the main computer used for evaluating the competition is strictly recommended before the race start.

As jj mentioned in his first post, at major events there has to be a backup timing system and this is usually (in Australia at least) a separate computer (which should also be synchronised with the SI Master station used to synchronise all of the event stations) linked to a second download station. Our competitors are very used to doing two downloads, in any case they don't get their splits printout until the second download!

All stations used at an event should be synchronised, including Clear and Check.

Synchronising the Start clock is important, but either the clock or the Finish stations may drift (but only by seconds or milliseconds at most) during the event.

@ Hawkeye: there are links to both OE and MeOS websites on the OA Technical page, and OWA's Tech pages have concise documents on SI Stations and Synchronisation.

We use MeOS and while I don't have the information about time offsets I will forward your question to those who do.
Jun 6, 2024 4:02 PM # 
At most events in the USA, btw, the SI timing is used for results. There are a few exceptions, but most events take the "easy" approach, and the runner's time is from the start punch to the finish punch. There have been cases when there has been more than one punch at the start and/or finish, and they weren't exactly synchronized. That usually doesn't make a difference, and when it does, it's unlikely that anyone will notice, but...
Jun 6, 2024 11:47 PM # 
You will notice if its a relay (or mass start) and you finish ahead of someone on the run in who punches the other (really, why have more than one?) finish station and they get placed above you. It has happened.
Jun 7, 2024 3:06 AM # 
Thanks for the comments - the guidelines most definitely emphasise prevention, however we do occasionally see oversights in event organisation so I'm trying to make it comprehensive.

O-ing - if you are in a head-to-head tussle in a mass-start or chasing-start race, the AUS rule (23.7) is that the first over the line wins.

The IOF rules are interesting - 23.7 mandates an electronic finish timing system (for major races) and 23.9 states that finish judges must rule on final placings, so theoretically possible for the compeitor with the faster electronic time to be placed behind a competitor deemed by the judges to have won?
Jun 7, 2024 4:54 AM # 
For sure, just a few weeks ago we had a mass start race with two finish punches. I was listed as having the same time as someone else, even though he was clearly ahead of me. Before publishing the results, I contacted all of the people who were tied or nearly tied to ask them what really happened.
Jun 7, 2024 5:18 PM # 
Hi Hawkeye,
not wishing to play with your name, but please note that IOF rules 23.7 and 23.9 are stated to apply specifically to two different types of competition and start procedure, therefore finish procedure also varies. Also please note rule 23.5, which to some people might read like they can choose an option "on the fly", but probably means one option shall be chosen pre-race, published, and followed throughout that race.

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