Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race

[Bulkan]

@zhang965 Nice park, I’ve ran there.

I remember saw a guy running fast with two watches…

[zhang965]

@Dimitrios-Kanellopoulos said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

@zhang965 Beidou?

both are gps+galileo

[isazi]

@zhang965 seems consistent with my Galileo experience: when it works, it works great; when it fucks up, it does it spectacularly.

Galmon also seems to point out to recent issues with Galileo satellites.

[zhang965]

@Bulkan said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

@zhang965 Nice park, I’ve ran there.

I remember saw a guy running fast with two watches…

last year, i ran a lot around of this park.

this year because of the obvious circumstance, I back to the park last month and my s9b gps got way worse than last year, sometimes I can see my speed dropping a lot even though I keep the same pace. (for example 4m/km drop to 7m/km during a while)

I don’t know what happened, does the covid affect the GPS satellites?

[Dimitrios Kanellopoulos]

Despite me being super excited by gallileo , I never use it.

I get the same experience with most.

Either great or siiiiittt.

Beidou and glonass seem the best for me.

[Fenr1r]

@zhang965 said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

I don’t know what happened, does the covid affect the GPS satellites?

You may have it backwards: GPS went Skynet on us, created covid and blamed 5G. In this case it’s just messing with you for shiggles.

[kabzior]

@Brad_Olwin said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

I would hope so too, the only thing I can think is they donated watches? I am a publishing scientist, not in this field but it is hard for me to imagine why the study was sponsored. It is possible the sponsor paid for the salary of a student or technician.

There is no need to guess, the authors have revealed everything in Acknowledgments:

Polar Electro Oy (Finland) funded this experiment in part. Polar Electro Oy provided the Swiss Federal Institute of Sport Magglingen (SFISM) with financial support to conduct the study. The funding was targeted for data collection, results analysis, and Polar reporting costs. Additionally, the products tested were provided by Polar. The Polar products were from the company stock directly and the other products were bought by Polar from stores and given to us for the period of the study. After termination, all products were returned to Polar. As agreed beforehand, representatives from Polar Electro Oy had no influence on the data collection or analysis or on the outcome of the article or any right to stop the SFISM from publishing the findings. The manuscript content does not necessarily reflect the views of Polar Electro Oy.

[Maryn]

@Dimitrios-Kanellopoulos said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

Despite me being super excited by gallileo , I never use it.

I get the same experience with most.

Either great or siiiiittt.

Beidou and glonass seem the best for me.

@Dimitrios-Kanellopoulos I recently apologized to the GPS only mode:)

[Dimitrios Kanellopoulos]

@Maryn same here

[Shrek3k]

Currently - which is approximateky the last 3 - 4 weeks - the GPS is not what it has been. I even tried it in combination with Beidou, had a few soft resets, always checked if the GPS-file has been the newest one - up to now nothing helped. Today I had the worst track on my Berlin-route.

I am really not sure what happened as this route has never been perfectly tracked, but nevertheless never with these errors either.
Screenshot from march

[sky-runner]

@zhang965 My observation is Suunto 9 is quite accurate on roads and straight trails, but the distance accuracy drops significantly when there are a lot of turnn and switchbacks, and especially at higher speeds e.g. running downhill as opposed to walking. For example I remember one case where I went with 3 friends, all wearing Fenix 5. On 2.5 mile uphill that was mostly straight up the distances matched pretty well and also were consistent with my previous runs with A3P. However on a 5 mile downhill, that had a lot of switchbacks Suunto 9 lost 0.4 mile compared to Garmin watches. Looking at the track it was obvious the distance was lost by cutting through switchbacks.

The point is that it may be quite accurate for some users and quite inaccurate for others. It seems Suunto has tuned Suunto 9 accuracy for road and strait trails where it used to overshoot distance initially due to wobbling. The right solution would be to use slightly different algorithms depending on activity type (e. g. road running vs. trail running) but I don’t know if that is possible.

[zhang965]

@sky-runner said in Suunto 9 with the recent GPS firmware was among least accurate GPS watches in today's 25K trail race:

@zhang965 My observation is Suunto 9 is quite accurate on roads and straight trails, but the distance accuracy drops significantly when there are a lot of turnn and switchbacks, and especially at higher speeds e.g. running downhill as opposed to walking. For example I remember one case where I went with 3 friends, all wearing Fenix 5. On 2.5 mile uphill that was mostly straight up the distances matched pretty well and also were consistent with my previous runs with A3P. However on a 5 mile downhill, that had a lot of switchbacks Suunto 9 lost 0.4 mile compared to Garmin watches. Looking at the track it was obvious the distance was lost by cutting through switchbacks.

The point is that it may be quite accurate for some users and quite inaccurate for others. It seems Suunto has tuned Suunto 9 accuracy for road and strait trails where it used to overshoot distance initially due to wobbling. The right solution would be to use slightly different algorithms depending on activity type (e. g. road running vs. trail running) but I don’t know if that is possible.

Let me explain the S9’s gps problem,

If we run straight, the gps accuracy is not bad, because s9 can calculate the distance with two points of locations. (in this cause, I remarked, I run with a speed A, but suddenly S9’s speed drops to speed B, 300 meters after it back to a speed C which is faster than A. in this case the final distance and average speed are good: I think during the part B, the GPS sign is lost, and during the part C, we got a compensated speed so it will not change the final accuracy).]

But if you run with a lot of turns, S9 calculates the distance for the part B with the straight distance between two locations. so you lost the distance.

[zhang965]

And I didn’t get the same issue last summer

[sky-runner]

@zhang965 Right, because Suunto 9 doesn’t produce a new point (and doesn’t calculates update for the distance) until distance from the previous point exceeds 10 meters. And in reality I observed 11-14 meters most of the time and sometimes even further. Suunto never advertisers that but Suunto 9 does this sort of smart recording based on distance between points even on the best quality, and it can’t be turned off.
I know this from looking at a lot of FIT files produced by Suunto 9.

[Dimitrios Kanellopoulos]

That is not correct. The production of gps points is not per se based on distance nor does the distance increase every 10meters. It depends on the quality of the Gnss

[nseslija]

@sky-runner SV welcome back to Suunto forum

[sky-runner]

@Dimitrios-Kanellopoulos May be you are right, but that is my observation from looking at multiple FIT files. Distance between points was pretty much always greater than 10 meters and the time between points was usually 3-4 seconds when running on trails, sometimes longer.

[Łukasz Szmigiel]

@sky-runner I’ve noticed there’s quality threshold in Suunto watches - watch won’t save a point if quality is below certain threshold. This way the path recorded is more sane in difficult conditions (less wobbly) but it may be refreshed less often.

[zvonejan]

@Łukasz-Szmigiel

hmm interesting. I have no complains about accurancy on suunto devices, but distance between ponts are between 3-15 meters.

suunto

but on garmin distance between points are consistent and much shorter

[sartoric]

Maybe (and maybe it was already explained) it’s a way to optimize “disk” space.
You don’t need to save N points for a straight line, 2 are enough, even if the watch is reading info every second.