[OT] ANT vs. ANT+

[Thomas Weichmann]

Hey guys,

I've been very interested in the real time GC stuff going on here. I has
looking on eBay for a cheap speed sensor and came across a "Suunto Bike Pod
Speed Sensor" for $12.00 USD. The guy says he is selling it because is is
not compatable with his Garmin 705, but he says that the speed sensor
transmits data in ANT.

I thought that Garmin read ANT, but when I asked the guy he said that the
Garmin only reads ANT+. Is there really a difference? I hear both of these
terms used and I just thought that it was people being lazy and dropping the
+ and just saying ANT. If there is a difference, which works with the real
time GC?

Here is a link to the eBay listing if you are interested:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330373394562

Thanks for your help,

Tom

[pa...@gch.sbrk.co.uk]

On Thu, Nov 05, 2009 at 08:01:12PM -0500, Thomas Weichmann wrote:
> I've been very interested in the real time GC stuff going on here. I has
> looking on eBay for a cheap speed sensor and came across a "Suunto Bike Pod
> Speed Sensor" for $12.00 USD. The guy says he is selling it because is is
> not compatable with his Garmin 705, but he says that the speed sensor
> transmits data in ANT.
>
> I thought that Garmin read ANT, but when I asked the guy he said that the
> Garmin only reads ANT+. Is there really a difference? I hear both of these
> terms used and I just thought that it was people being lazy and dropping the
> + and just saying ANT. If there is a difference, which works with the real
> time GC?

ANT is a low level communications protocol that allows you to send a
message of any format to anywhere and doesn't define the frequency,
network key or other parameters.

ANT+ is a higher level protocol that specifies all the communications
parameters and data format and thus allows interoperability.

Although the 705 could read the Suunto Bike Pod transmissions if it
were programmed to do so, it isn't and can only read those that are
transmitted according to the ANT+ bike speed/cadence profile.

Real time GC using quarqd would only read ANT+, however it would
be potentially possible to read the Suunto bike pod transmissions
too, providing somoene spent some time decoding them. You would
need a generic ANT receiver such as the Garmin USB ANT stick
or the Suunto PC POD (not recommended).

Paul

[Thomas Weichmann]

Thanks for the clarification guys!.

[Justin F. Knotzke]

2009/11/6 Thomas Weichmann <t...@weichmann.org>

Thanks for the clarification guys!.

   Bontrager has a speedo that is ANT+. They want $70 USD. Which, if you ask me, is a little steep for a reed switch and ANT+ chip.. But that, coupled with a Garmin/Sparkfun USB ANT+ stick and you'd be in business.

   IIRC, we want to support simulated racing for speed and or watts with some conversion mechanism to even it all out. Obviously, it's never going to be perfectly accurate, but the goal is to have fun.. 

   Hopefully you can find one and join us. Golden Cheetah simulated racing is not far away !

   J

[Jamie Kimberley]

On Fri, 6 Nov 2009, Justin F. Knotzke wrote:

> IIRC, we want to support simulated racing for speed and or watts with
> some conversion mechanism to even it all out. Obviously, it's never going to
> be perfectly accurate, but the goal is to have fun..
>
> Hopefully you can find one and join us. Golden Cheetah simulated racing
> is not far away !
>
> J
>

Do we need speed?? It seems that sped would be overly dependent
upon the trainer/rollers setup that you are using. I can't see a
good way to even that out between riders. With power data alone you
should be able to use some models to predict speed.

Thanks,
Jamie

"It is a mistake to think you can solve any major problems with just
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__________________
Jamie Kimberley
Postdoctoral Fellow
Department of Mechanical Engineering
The Johns Hopkins University
Office: 410.516.5162
Mobile: 217.621.8272
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E-Mail:jamie.k...@jhu.edu

[Justin F. Knotzke]

2009/11/6 Jamie Kimberley <jamie.k...@jhu.edu>

Do we need speed??  It seems that sped would be overly dependent upon the trainer/rollers setup that you are using.  I can't see a good way to even that out between riders.  With power data alone you should be able to use some models to predict speed.

   Not everyone can afford a power meter.

   J 

[Jamie Kimberley]

On Fri, 6 Nov 2009, Justin F. Knotzke wrote:

Agreed. The question of how to calibrate the response based on speed
data alone remains.

Since you raise the issue of finances, I'd hate for someone to run
out a buy an ant+ speedo & receiver to find out that they can't
"race" with others because we don't have a good way to calibrate
their effort.

I suppose that we could try to have those of us with powermeters
provide calibration curves for different trainers. There will be
differences due to tire compression, and unit-to-unit variations
for the same model, but probably a decent place to start.

Anybody have any thoughts?

[Justin F. Knotzke]

2009/11/6 Jamie Kimberley <jamie.k...@jhu.edu>

Since you raise the issue of finances, I'd hate for someone to run out a buy an ant+ speedo & receiver to find out that they can't "race" with others because we don't have a good way to calibrate their effort.

   I don't think that will be an issue. It's not a show stopper. It's just a question of coming up with something that is "good enough".

   Remember, the scope is pretty loose. The UCI won't be sanctioning these races. ;-) 

   There's lots of different ways to cheat.. especially since it's open source. So with that said, we just need to come up with something that'll do. We could make it tweakable. 

   We didn't want to get caught up in this debate right now as we are too busy just trying to get the game-play part worked out. We did however state that we want as many people to join up as possible. So the requirement was a speedo will do. This is the kind of debate that could go on forever, as matching speed to watts perfectly is nearly impossible. 

   J 

[Berend De Schouwer]

Jamie Kimberley wrote:
> On Fri, 6 Nov 2009, Justin F. Knotzke wrote:
>
>
>> 2009/11/6 Jamie Kimberley <jamie.k...@jhu.edu>
>>
>>
>>> Do we need speed?? It seems that sped would be overly dependent upon the
>>> trainer/rollers setup that you are using. I can't see a good way to even
>>> that out between riders. With power data alone you should be able to use
>>> some models to predict speed.
>>>
>>>
>>>
>> Not everyone can afford a power meter.
>>
>> J
>>
>
> Agreed. The question of how to calibrate the response based on speed
> data alone remains.
>
> Since you raise the issue of finances, I'd hate for someone to run
> out a buy an ant+ speedo & receiver to find out that they can't
> "race" with others because we don't have a good way to calibrate
> their effort.
>
> I suppose that we could try to have those of us with powermeters
> provide calibration curves for different trainers. There will be
> differences due to tire compression, and unit-to-unit variations
> for the same model, but probably a decent place to start.
>
> Anybody have any thoughts?
>

A 1kg weight on the pedal, a level, and a stopwatch? No idea if that
will be anywhere close to accurate, but it's friday.

[Mark Rages]

On Fri, Nov 6, 2009 at 7:28 AM, Justin F. Knotzke <jkno...@shampoo.ca> wrote:
>
>
> 2009/11/6 Thomas Weichmann <t...@weichmann.org>
>>
>> Thanks for the clarification guys!.
>
>    Bontrager has a speedo that is ANT+. They want $70 USD. Which, if you ask
> me, is a little steep for a reed switch and ANT+ chip.. But that, coupled
> with a Garmin/Sparkfun USB ANT+ stick and you'd be in business.

Is this the one?

http://bontrager.com/model/08895

They claim $30 MSRP for the speed sensor. I'm pretty sure I've seen
that sensor with other brands on it:
http://www.saris.com/p-337-speedcadence-sensor.aspx

Garmin has their GSC-10 speed / cadence combo sensor for ~$50.

Regards,
Mark
markrages@gmail
--
Mark Rages, Engineer
Midwest Telecine LLC
mark...@midwesttelecine.com

[Justin F. Knotzke]

2009/11/6 Mark Rages <mark...@gmail.com>

Is this the one?

http://bontrager.com/model/08895

   Sorta, this one: http://store.trekbikes.com/jump.jsp?itemID=2336&itemType=PRODUCT&path=1,2,15,445,449&iProductID=2336&bShopOnline=1

  J 

[pa...@gch.sbrk.co.uk]

On Fri, Nov 06, 2009 at 08:28:42AM -0500, Justin F. Knotzke wrote:
> Bontrager has a speedo that is ANT+. They want $70 USD. Which, if you ask
> me, is a little steep for a reed switch and ANT+ chip.. But that, coupled
> with a Garmin/Sparkfun USB ANT+ stick and you'd be in business.

For US people, there's someone selling Garmin GSC 10 ANT+ speed/cadence
devices for $17 on ebay (including delivery).

Paul

[Mark Rages]

Their website is confused. Is that a speed sensor, cadence sensor, or
heart rate belt?

[Mark Liversedge]

At the risk of opening the wound on speed calibration, we could ask a
user top spin up to 25 kph and then time how quickly it gets back to
say 15kph when they stop pedalling, We can then calculate a rolling
resistance from that, then use that in any calculation or speed to
power.

That is kinda how the CT works anyway.

Regards,
Mark

[Justin F. Knotzke]

2009/11/6 Mark Rages <mark...@gmail.com>

On Fri, Nov 6, 2009 at 10:27 AM, Justin F. Knotzke <jkno...@shampoo.ca> wrote:

Their website is confused.  Is that a speed sensor, cadence sensor, or
heart rate belt?

   Or the clip to hold the heart rate belt? ;-)

   I agree, it's totally whacked.

  J