iAero "Filter" function

[jvandyk]

I recently paired a Cinqo with my iAero. At this time I have only used the iAero as the computer head to record the Cinqo's power data as it has been too windy here to do the 4 mile calibration ride without dealing with heavily gusting winds so no comparisons can be made between the two units per se.

I had set the iAero Filter function to "On" and as I understand it from the manual, this will smooth the data over a 4 seconds period of time so that when viewed on the screen it doesn't jump around so much. Now I did a few accelerations and sprints on some small rollers and I did see >750W a few times on the iAero screen but when I downloaded the file, the highest recorded wattage reported was ~346W. I imported the iBike file into WKO+ and it showed the same low wattage. Is this due to the Filter function being turned "On" and is it my power recorded/smoothed over a 4 second period of time? If I was to turn it "Off" would I see more variable power data and of course the higher/peak values I seek?

My intention is to track my power production across a range of time periods and how they change with training over time in WKO+.

Has anyone used a Garmin with the Cinqo and does it have a filter function too? What are the results?

Thanks for the help.

Jack

[coachboyd]

can you send me that file to boyd (at) totalcyclist dot com

I'll take a look at it for you.

[jvandyk]

Thanks Boyd but I think I figured out the issue on my end. It seems that the first 25min of my ride (where the higher power values should have been) did not record or was saved to a seperate file which I have already cleared from the iAero.

I will try this again and see if things appear as they should for me.

In the meantime, could you elaborate more on the Filter function - benefits, better to use in certain scenarios versus others, what specifically is being recorded and shown - is there much difference between no filtering versus filtering in reported power when viewed in the software?

Jack

[coachboyd]

The filter is good for people who don't like how much wattage jumps around (it also prevents those big power spikes that randomly happen from an SRM, not our fault but we fixed their problem).

If you are trying to hold a specific wattage on the flat, you will notice that wattage can be all over the place if you are not experienced at holding specific numbers. This helps the user target in a little better.

In your download, are you sure that you are looking at the DFPM power? Also, if your ride is breaking into separate ride files, you may want to check your battery. This is a new feature we made where it automatically splits the ride file when the battery gets below a certain level. This is to prevent a corrupted file from happening and making you lose all your ride data.

[jvandyk]

I wasn't careful enough when I downloaded the files from the iaero. My file name was showing 45km and the total ride time was 90min but all that remains is 37.2km over ~72min. Granted the temperature was dropping in my area (Calgary Alberta) so I know the battery was being affected until I returned home and finished on the trainer.

If I understand correctly then from your response there is no difference reported when the data is downloaded into the iBike software when the filter is either on or off. Sorry for the confusion but I don't feel that you quite answered my original question - "is there much difference between no filtering versus filtering in reported power when viewed in the software"?

[coachboyd]

If I remember right, there is a slight difference when downloading with the filter. This is so that we could get the SRM to stop showing random blips of 2800 watts throughout the ride.

The filter is very small, and brings the update frequency right at where the iBike power is when using just the iBike.

[kylef]

would it be possible to make the filter configurable? That is, make the moving average adjustable? The Ergomo headunit was pretty cool in that you could specify the display to show a configurable average of the last 1-9 samples. (actually, I think it was pedal strokes, not samples, but anyway...)

[Velocomp]

This is a nice idea.

[Morocco Mole]

Not 100% sure how it works now, but I would be great to have the display filter configurable as above, but still have the iBike record at the highest resolution, eg 1 second.

Thanks

[kylef]

Not 100% sure how it works now, but I would be great to have the display filter configurable as above, but still have the iBike record at the highest resolution, eg 1 second.

Thanks

That's exactly what the Ergomo computer did: it recorded at the highest sampling rate, but the user display was a moving average of the last 1-9 pedal strokes (since Ergomo sampled based on crank revolutions ).

For the "max values" screen on the display you'd want the raw data, not averaged over some samples. But in all honesty the max value on the computer display don't mean much to me.

[thassman]

i can´t really see any difference on the fluctuation of the power numbers, regardless of the filter is on or off.
Can anyone confirm that this smoothing actually works, with firmware 4.16 ?

If it works, will the 1 sec power recording be affected by it, in any way ?

My DFPM is a Quarq cinqo saturn


thanks
Tommy

[noel]

I was just wondering unless you are in the small cog 13 to 11 and pulling some phenomenal RPM, 794 watts on the rollers does not seem right. The lower numbers seems the right one.

[kylef]

I hate to say "me too", but me too. I've got the latest firmware but I do not notice any difference with or without the filter.

i can´t really see any difference on the fluctuation of the power numbers, regardless of the filter is on or off.
Can anyone confirm that this smoothing actually works, with firmware 4.16 ?

If it works, will the 1 sec power recording be affected by it, in any way ?

My DFPM is a Quarq cinqo saturn


thanks
Tommy

[coachboyd]

The filter is a very slight one. Seeing the power numbers change and trying to lessen that change while doing intervals is one of the key points in power training. It makes a more effective rider.

The filter we enabled was mainly to deal with the 2800 watt spikes that the wireless SRM would send out fairly regularly. We're not sure why those spikes happened, but we fixed it for them.

[Steve_Davidson]

The filter is a very slight one. Seeing the power numbers change and trying to lessen that change while doing intervals is one of the key points in power training. It makes a more effective rider.

The filter we enabled was mainly to deal with the 2800 watt spikes that the wireless SRM would send out fairly regularly. We're not sure why those spikes happened, but we fixed it for them.

I've noticed the occasional spike when the SRM values are first shown on the screen when starting off. For info as far as I can tell this doesn't happen with the PCVI (friend has iAero and PCVI). It must be something to do with the data packet sent when the two reed switches are activated on the first revolution. Other than that I've not seen any other spikes with the SRM. The filter doesn't appear to do much as far as I can determine as it happens whether on or off.

Another friend has got a Garmin head unit that I might be able to borrow to try out.

Steve

[thassman]

thanks for the clarification, it would be really nice to be able to configure a 3 sec rolling average.