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Old 07-17-2011, 01:26 PM   #15 (permalink)
bwilson4web
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Quote:
Originally Posted by dcb View Post
Just checking, you realize every other row is missing a battery measurement?
Yes, it is how the Graham miniscanner is reporting the data. I've attached the source and 'normalized' data.

The Graham miniscanner starts by sending a set of "..." as a timing clue for downloading a software update. Then it writes the first data timestamp and data:

2.840<TAB>0.0<CR><LF>
2.840<TAB><TAB><TAB>0<CR><LF>

The first and third data requested are MG1 torque and MG1 rpm. Since these come from a single response packet, the Graham miniscanner reports both values from the first packet which is why the first two data records have the same time stamp. Then comes:

3.357<TAB><TAB>0.0<CR><LF>
3.357<TAB><TAB><TAB><TAB>0<CR><LF>

The second and fourth data requested are MG2 torque and MG2 rpm. Again, they came from the same response packet so we get two, identical time stamp records from one data request.

So the third and fourth data requested are MG1 rpm and MG2 rpm and again, the Graham miniscanner is reporting the first and second items that come from the same response packets:
3.873<TAB>0.0<CR><LF>
3.873<TAB><TAB><TAB>0<CR><LF>
4.389<TAB><TAB>0.0<CR><LF>
4.389<TAB><TAB><TAB><TAB>0<CR><LF>

The fifth and sixth data elements are traction battery voltage and current:
4.907<TAB><TAB><TAB><TAB><TAB>0<CR><LF>
5.396<TAB><TAB><TAB><TAB><TAB><TAB>0.0<CR><LF>

These are separate requests and response packets so the time stamps change. But to minimize sampling errors, we use these two in the spreadsheet to calculate the traction battery power drain or charge.

So what happens when we normalize the data is:

A) MG1 torque, MG2 torque, MG1 spin, MG2 spin
B) MG1 torque, MG2 torque, MG1 spin, MG2 spin, Batt Volt, Batt Amp

It looks like the traction battery data is only every other record but it is easy to miss that there are two separate MG1/MG2 records. All of the data is there and clustered so the most time-adjacent data is in a single record.

Bob Wilson
Attached Files
File Type: txt 110715_134954.txt (18.8 KB, 29 views)
File Type: txt 110715_134954_csv.txt (7.2 KB, 36 views)
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