Bangle.js 2 cycling (riding on bike) set up.

[espruino-discuss2]

Posted at 2022-08-30 by RomanistHere

Hey guys, I'm wondering if someone came up with a stable set up for 2-3 hours cycling. I'm talking about GPS + heart monitor. I had high hopes for GPS location and detecting current speed, distance and other stuff based on it, but if I set up GPS measurements every 10s, my battery drains in like 40 minutes. True, that for average distance/speed for a few hours ride measurements every minute or 2 would be enough, but it will never give the actual current speed. I wanted to write an app for that, but since it's going to work only for 40 minutes, it doesn't make a lot of sense. Note: I don't want to use phone (through bridge) for it. I wouldn't need a watch if I wanted to.

Another thing is heart rate. Because of vibrations and idk why it could show something like 190 bpm and then 15 in the range of a few minutes. I understand, that watch is not the best thing to measure your heart rate. Probably someone used some heart sensor like for example like this one: https://support.polar.com/uk-en/support/H10_heart_rate_sensor and managed to connect it to Bangle.js.

I would very much appreciate if you shared your experience with any of these problems or recommendations.

[espruino-discuss2]

Posted at 2022-08-30 by user140377

For the HRM part: Check the https://banglejs.com/apps/?id=bthrm app (click on read more). It should list compatible belts.

GPS/Battery: With recorder at 10s I get at least 4 hours (Have not tried with heart rate).
How long does your battery last usually when not using GPS?

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Posted at 2022-08-30 by RaoulDuke

If you seriously want to save battery, you might look into BLE wheel and heart rate sensors. If you mount the watch to your bars, you could also power if with an external battery or a hub generator.
40min sounds very short, my watch easily lasts more than two hours with the tinyVario app, so there might be a problem with your code as well. (tinyVario used GPS and barometric sensor, no heart rate)

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Posted at 2022-08-30 by RomanistHere

How long does your battery last usually when not using GPS?

with BLU off and nothing but pedometr and clock working - around a month

It should list compatible belts.

Thanks, didn't notice

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Posted at 2022-08-30 by RomanistHere

I tried "recorder" and "gps recorder" apps, but only once. Probably needs more testing

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Posted at 2022-09-01 by Fteacher

@RomanistHere , I use a Oh1+ from polar, the bthrm app mentionned above and the run app. The gps recorder is set on 1 sec and I also record bthrm. My longest run was 1h20 and I still had battery left. I suspect it can take almost 3 hours with these settings, so there's definitively something wrong with your watch.

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Posted at 2022-09-01 by Mi

H10 works perfectly well. Also does not drain much energy.
Haven't specifically measured, but remember have worn it for hiking whole day and didn't see much difference (without GPS!).
Update: used recorder app