Left/Right Power?

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lbville
Posts: 1
Joined: Mon Feb 20, 2017 11:08 pm

Left/Right Power?

Post by lbville »

Maybe I'm missing it but is there a way to see power generated by left leg vs. right leg in Isaac? I see wasted watts, etc (yikes, btw) but would love to be able to see L/R power.
tangible
Posts: 1
Joined: Sun Feb 19, 2017 10:25 pm

Re: Left/Right Power?

Post by tangible »

New User, PowerPod w/Powerstroke option received two days ago.

I have the same question! Hopefully our friends at Velocomp will reply.
Velocomp
Velocomp CEO
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Joined: Fri Jan 11, 2008 8:43 am

Re: Left/Right Power?

Post by Velocomp »

The left and right legs of most cyclists do not apply power equally as they turn the crank, nor is each leg equally as strong.

If you look at the crank plot of PowerStroke you'll see how your left and right legs apply power, every 10 degrees as you turn the crank. The PowerStroke distribution shows how your legs are accelerating the bike, as you turn the crank.

If one leg is stronger, then more acceleration dots from that leg will extend outside of the green oval.

If one leg is "lazy", then the number of dots outside the circle will be fewer.

If your legs are equally balanced, if your cycling technique is strong, and if you have a great bike fit, then the dots will adhere very nearly to the green oval at nearly all points.

That's what PowerStroke tells you.

In the image below, from one of my recent bike rides, my right leg is doing a lot more work than my left leg--both in terms of strength, and in terms of the amount of time it is working.

So, I need to work on my left leg.

The other guys give you a simple L/R power split. Why nothing more? It's because strain gauge sensors can't usefully measure what is really going on.
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John Hamann
GooseRider
Posts: 58
Joined: Wed May 10, 2017 10:52 am

Re: Left/Right Power?

Post by GooseRider »

John,

Thanks for the explanation! Would still be interesting to see a balance number. It would even be cooler if one could see balance in the Garmin headunit in real time. Don't know if you are able to distinguish with enough accuracy to do that?

Thanks,

Morten
ronpei
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Joined: Sat Jun 08, 2013 7:47 am

Re: Left/Right Power?

Post by ronpei »

since the power pod/ Newton is capturing power reading at such a high frequency, one would think that it would be rather trivial math to add a line in the power stroke display that captures the left right balance as a percentage? Just one more piece of info to improve pedaling dynamics. If a user has power stroke it would be a nice metric to add to the main page as an average for the ride?
TuRu00
Posts: 69
Joined: Wed Jan 04, 2017 9:34 am

Re: Left/Right Power?

Post by TuRu00 »

I am agree, PowerStroke it is a great feature but I think that a step ahead could be done...

1) Reading, writing into .ibr and broadcasting (via ANT+) the balance, torque effectiveness and pedal smoothless data from a DFPM.
2) Using that data, if available, to complete PowerStroke analysis. I think that a good pedal stroke it is not just about the motion of a handlebar, specially the torque effectiveness of the pedal stroke combined with the motion can help to improve (and train) the pedal stroke.

What do you think?

Thanks!
Velocomp
Velocomp CEO
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Re: Left/Right Power?

Post by Velocomp »

This is not as simple a calculation as it might seem. Isaac is doing a h*** of a lot of processing in the background.
John Hamann
ronpei
Posts: 120
Joined: Sat Jun 08, 2013 7:47 am

Re: Left/Right Power?

Post by ronpei »

I do not discount that the power stroke is doing a lot with respect to dealing with the accelerometer data and using an algorithm to translate that into what you show with respect to timing it to the right and left pedal stroke based upon the position of the left crank arm, and maybe I am being optimistic. I thought that you had said that you capture the power data , which I do understand is a complex calculation, at a frequency faster than 1 per sec. So it may be that the calculation to get a power number more frequently than once a sec, at a minimum of 20 data points per second. So yeah that might be a bit too much to get a wattage that hits that frequency or higher, one could probably figure out which leg is which, but again there has to be a trigger signal from the cadence sensor to align thing to make it all easier. Anyhow this right left balance data or graph, be it sinusoidal or a spider graph would be really more informative to me or in addition to the current data so that I can see this alone or in addition to the current display. That would be very positive and allow you to go head to head with the so called dual sided or other strain gauge metres that give a traditional left right balance... just more apple to apple is all I am saying. I realize it may be a lot to ask for but what the heck, it is worth a try.
kdx200
Posts: 171
Joined: Sat Jan 14, 2017 10:09 am

Re: Left/Right Power?

Post by kdx200 »

I think all data anda explanation(the dots degrees, the dots quantitites, etc) John told many posts above can be added to the actual powerstroke graphics/video... the pp has the data anda think tus easy to add.
In fact i think its easy or more easy than do and all new GUI that the isaac is shouting for.

Thank you
Velocomp
Velocomp CEO
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Re: Left/Right Power?

Post by Velocomp »

Check out this video we made a while back...

https://www.youtube.com/watch?v=mdPH29kkjsI
John Hamann
kdx200
Posts: 171
Joined: Sat Jan 14, 2017 10:09 am

Re: Left/Right Power?

Post by kdx200 »

John thank you, i watched this video many times.
I only was suggesting about the numbers that exists inside the pp and we cant see in the powerstroke app.
Also and only as a fan and customer of velocomp or pp, the isaac really neeeds to be upgrade in terms of look and feel and some minor options. As i said the hard side is to get the data and is already in the pp... take note iam only talkimg about the isaac that is post ride. I know that live/online data stream to the head unit is not simple and is another history.

Thank you for your permanent attention
BBQcyclist
Posts: 49
Joined: Mon Apr 10, 2017 8:38 pm

Re: Left/Right Power?

Post by BBQcyclist »

Re. "...as a fan and customer of velocomp or pp, the isaac really neeeds to be upgrade in terms of look and feel..."

As a fan of PP - I also fully agree
TuRu00
Posts: 69
Joined: Wed Jan 04, 2017 9:34 am

Re: Left/Right Power?

Post by TuRu00 »

BBQcyclist wrote:Re. "...as a fan and customer of velocomp or pp, the isaac really neeeds to be upgrade in terms of look and feel..."

As a fan of PP - I also fully agree
I would suggest to integrate the powerpod specific functions into GoldenCheetah, and use GoldenCheetah as a foundation. It could be a good mix.
Velocomp
Velocomp CEO
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Re: Left/Right Power?

Post by Velocomp »

Well, I know I'm going to get into trouble for this post...

For the first time ever I downloaded Golden Cheetah. I opened it up and (I think) was presented their sample ride file. This is the screen GC presented to me. I took a screen shot of it, below.

Really?

GC may have some interesting analytical capabilities, and I'm sure that, after you "learn" GC, it can be useful.

But this kind of daunting data presentation will, in my opinion, cause too many cyclists throw away their power meter.
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John Hamann
TuRu00
Posts: 69
Joined: Wed Jan 04, 2017 9:34 am

Re: Left/Right Power?

Post by TuRu00 »

Don't know if your screenshot is the default view or not, but i do like this kind of representation:

Summary:

http://www.goldencheetah.org/img/RideSummary.png

In wich PowerPod could include their own metrics specially from PowerStroke, CdA when available, DFPM power and PowerPod power and so on.

More detailed graphics:

http://staminist.com/file.php/1/359/gol ... t_copy.jpg

In wich powerPod could include their own metrics (CdA, wind, wasted watts, and so on).

Out of that, specially trends is very useful, in Isaac there is no way to "plan" and "track" a season.

I don't mean that GC is the perfect tool, nor the best look and feel, just mean that it could be a good foundation...
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