I'm trying to develop an accurate and responsive GRADE metric in CIQ. It isn't as easy as you might think. Elevation data bounces around especially on grades that are relatively small like in the 1-3% range. You have to smooth out the bad data over several readings, but also need a quick response to slope changes.
Garmin does a good job with their internal GRADE metric. They obviously use features other than Elevation and Distance. We know GPS elevation is not useful, so it must be something else. Maybe the accelerometer? For example, I might be starting up a climb and for a few seconds, the barometer shows no change or might actually bounce down a foot or two for the first reading or two on the new climb. But the Garmin GRADE metric accurately shows I'm on a 1-2% grade almost immediately.
So three questions:
1. Do we know if Garmin intentionally hamstrings CIQ in some areas? Not exposing GRADE in the Activity.Info is just one of a number of native metrics that would be very helpful but not given to CIQ developers. There might be valid business reasons to hold back some capabilities - but I can't think of any.
2. Does anyone know what Garmin might be using to generate an accurate GRADE metric?
3. Since barometric data and distance doesn't, by themselves, provide the accuracy and responsiveness needed to produce a GRADE value that can match the performance of Garmin's internal GRADE value.... is there something else we can tap into via CIQ to help improve that metric?