Pool swimming - counting laps algorithm

Tieutieu

@kamarasm said in Pool swimming - counting laps algorithm:

Hi Guys,

May I have somebody to explain to me the algorithm what S9B using for measure laps in pool swimming?
My question is that it can measure laps in case I’m not doing flip turn?

Thanks a lot,
Marcell

Not sure but I’d bet it is mainly based on the accelerometer sensor + perhaps compass. Even lap counting isn’t always very accurate, it works even if you’re not doing a flip turn.

Egika

@kamarasm yes of course. I can’t flip turn but am swimming from time to time in a pool. The laps count is based on the accelerometer.

You want to make sure:

that you firmly push away from the wall and have some gliding phase. This will ensure to get the turn registered.
you don’t get interrupted too much during the lane (like stopping and waiting for things to get out of the way), as this could introduce extra laps.

kamarasm

Thanks a lot Guy, it was really useful.
I hoped Suunto figured it out as carefully as they used to.

Ars Vitae

@Egika said in Pool swimming - counting laps algorithm:

@kamarasm yes of course. I can’t flip turn but am swimming from time to time in a pool. The laps count is based on the accelerometer.

You want to make sure:

that you firmly push away from the wall and have some gliding phase. This will ensure to get the turn registered.

you don’t get interrupted too much during the lane (like stopping and waiting for things to get out of the way), as this could introduce extra laps.

I am not sure that these conditions are sufficient. I tested the SV yesterday and it did not count the whole 400 m (out of the 1500 m I did in total), even though approx. 300 m (I am 200% sure of this) was done with the exact terms you describe. I hope I am referring correctly to the thread that a similar algorithm was used in SV? If so I would ask for more information on how exactly this algorithm counting pool laps works.

Jamie BG

@Ars-Vitae

Was it short or long i.e. too few laps or did it count too many laps.
Did you do sets or all one long set?

Genernally too short means push off wasn’t good enough in some instances.

Ars Vitae

@Jamie-BG said in Pool swimming - counting laps algorithm:

Was it short or long i.e. too few laps or did it count too many laps.
Did you do sets or all one long set?

Genernally too short means push off wasn’t good enough in some instances.

Thanks for your reply.

I don’t understand the first question.
What do you mean by making sets or one long set? I did a rather classic swim workout: warm-up (300), technique exercises for the four styles (600), legs (200), time regime exercises in crawl (400) and cool down (100).
I’m sure the push off was good.

Egika

@Ars-Vitae 1. did it count too many laps or too few?

Ars Vitae

@Egika Like I wrote: “I tested the SV yesterday and it did not count the whole 400 m”.

zadow

@Ars-Vitae for kick drills, does not matter how hard you push off the wall or whether you slide long enough. kick drill lanes are not counted.
As a triathlete I swim quite a lot. kick drill laps are never counted. Not even one hand drill, when one hand is still (that one where I have the watch on), is not counted as well.
In general, accelerometer is the only sensor (IMHO) which is taken into account. However, you have to use your hands for a lane to be counted in. Does not matter which swim style you are swimming.
And yes, it is not 100% accurate. It happens quite often that it counts some lap more or less. Accelerometer can be fooled easily with unpredictable moves, when you hit the other swimmer in lane…

Ars Vitae

@zadow said in Pool swimming - counting laps algorithm:

However, you have to use your hands for a lane to be counted in.

What do you mean: “However, you have to use your hands for a lane to be counted in”? How you have to use your hands?

zadow

@Ars-Vitae yeah, sorry for confusion, lost in translation. I mean, accelerometer can detect new lap only when you are swimming (free style, crawl, medley, whatever…) If your hands are still, like for example during kick drill or some rotation drills, acceleromateer cnnot detect new lap…obviously…hand is still…
hope I explained it better now…