RE: Question regarding CSCS demo measurement values

daubsi — Wed, 11 Nov 2020 15:25:59 GMT

Thanks Jørgen!

RE: Question regarding CSCS demo measurement values

Jørgen Holmefjord — Wed, 11 Nov 2020 14:00:22 GMT

Hi,

As far as I can understand the last_wheel_event_time delta is the time spent for increasing the cumulative wheel revs. The example only adds full revolutions to the cumulative_wheel_revs parameter, while the remainder is saved for next measurement. If the remainder is close to a full revolution, it may cause the next measurement to increase multiple revolutions (like you see happens on line 3 and 5), but parts of the revolutions may have happened in different measurement intervals. If you average the delta over many measurements, it should get close to 1024 if I'm not mistaken.

I'm not exactly sure what is causing the crank time of 119, but it could be that if the remainder of the crank_rev_degrees modulo operation is larger than the degrees_per_sec will give a negative increase in event_time, which may cause some strange behavior. I do not think that the simulator values should be taken as a reference, the accuracy of this may not be very high. It simply generates increasing/decreasing values, and there are performed some calculations on these to give pseudo-random numbers for the service.

Best regards,
Jørgen