It's hard to explain - just tried putting them side-by-side for a video but if I put them both on my wrist the performance depends on which order they're in.
Here are two screenshots...
Red is the filtered value (which is then peak detected)
Purple is the raw HRM value (with DC bias removed)
Green is the raw value from the HRM
The one on the right is the new VC31B. The actual signal varies less with heart rate, but it's much 'cleaner' - I believe the sensor itself probably has a higher dynamic range.
I run the new one at 25Hz rather than the old one's 50Hz as well, which helps with power consumption. Even at half the rate it seems to perform slightly better
I run the new one at 25Hz rather than the old one's 50Hz as well,
Hmm. That should be fine for counting BPM, but other metrics will probably require a higher sampling rate. What is the range of tge sensor? In theory, could apps request a higher sampling rate for specific purposes?
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It's hard to explain - just tried putting them side-by-side for a video but if I put them both on my wrist the performance depends on which order they're in.
Here are two screenshots...
The one on the right is the new VC31B. The actual signal varies less with heart rate, but it's much 'cleaner' - I believe the sensor itself probably has a higher dynamic range.
I run the new one at 25Hz rather than the old one's 50Hz as well, which helps with power consumption. Even at half the rate it seems to perform slightly better
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