Cloudspin

You have to use the exact same long & lat point names that your logger uses. On my Solo DL they are GPS_LonAcc & GPS_LatAcc. You can tell which your logger is using by opening an existing test and looking in the Measures column.My car has values generated by the logger GPS and another set generated by the my car's internal GPS. I think the experts (Matt, Pro Coach, Jerry) recommend the GPS generated ones as opposed to the SM (on my logger) variety.

linzman

I did that, and the formula worked in my session window. But when I tried to move it to the general window to automatically apply to every session, it didn't recognize those channel names

Cloudspin

Did you Follow the steps in Matt's post #8 on the first page?

Matt Romanowski

That's ok. The General Tab will kick out most channel names. If it works in an open test (the other tab), then it will work when automatically input on file opening (of a newly downloaded test).

Sorry that I didn't explain that better before. There are some small details in math channels that can trip people up and this was one of them. But, you'll really like using the general tab now so all your new tests will have the same set of math channels without having to import them.

linzman

Thanks Matt. I guess I'll have to wait til the spring to find out.

Matt Romanowski

If you have an MXL2, MXS, MXG, you can make it record when you are connected with your laptop even if the car isn't running/moving. If it's an MXL or Evo4, you'll have to start the car to get it to record.

Let me know what you find at either time. I hope this video/thread gets people to learn some new things with their data. It's great to have people experimenting and learning.

Cloudspin

I've been able to get a bunch of these entered tested and saved under the General tab using your guidance above. All good. I am having one recurring issue though. I started out entering them in the order they are listed in AiMSports_LearnFast_Maths_Oct_2015 (1).pdf. When I got to CST On, I got this error message when testing it:

The formula uses some channels that are computed later. Reverse channels order.

It highlighted one of the identifiers, so I rewrote the whole thing placing that identifier into the last place of the string. Re-tested it and got the same error message but it highlighted one of the other two identifiers. After too long of trying things like this, I deleted CST On entirely, hit OK which then closed the Modify Math channels dialog. I reopened it, entered CST On as a new channel and everything worked fine so I thought I was home free.

I continued down the list and CST Lap T went well but then I got the same error message shown above when trying to test CST LapD. It highlighted CST On as the offending identifier. I did use GPS_Speed from my logger's list and not just "Speed" from Roger's pdf so its not that.

I remember one of you guys writing about having to be careful of the order of these additional math channels but can't find where that was posted. I thought following the order of Roger's list would be the way to go but something's not right. Any recommendations? After not getting many track days during the spring, summer and early fall, I got 5 days at Sebring over three consecutive weekends in November (DMTD, Chin, PDG) and obliterated my previous PB multiple times so I have a lot of good data to analyze and try to get another couple seconds before it gets hot (hotter?) again.

Thank you for all the assistance!

Mike

ProCoach

The reason for this is because most folks are not very diligent in calibrating their electromechanical accelerometers.

On a Solo DL, you would place the car on flat level ground, connect via USB to your laptop, fire up the Solo DL and from Race Studio 2, select "Device Calibration."

Then, select "Auto-Calibrate all sensors" and click "ok"on the bottom of the dialog box.

Cloudspin

^ Just make sure you download any undownloaded data prior to calibrating the logger. Yes, I learned the hard way!

Matt Romanowski

I didn't look back at the channels, but you have to make sure that any math channels that are used in another channel are listed before it's used. For example, if you need "brake on" to calculate coasting, brake on has to be in the list before coating.

Cloudspin

In all cases the prerequisite channels, for lack of a better term, have been identified prior to generating the ones that don't test successfully and result in the error message. Probably better to not worry about it now. I looked at CST On on few previous laps and it only displayed "1" three times per lap and never after turn 13. That can't be right in my case as I know from looking at throttle position and brake pressure traces that I am slow to transition to braking in the fast corners, notably 1 & 17 and often in 16 for some reason.

I think my next step is to read up on how to interpret GSum traces in an effort to improve. I've seen several posts and links to other sites on the subject but haven't read them yet. It was beneficial to learn the mechanics of adding math channels though so thanks for that!

PS - just saw this:
https://rennlist.com/forums/racing-a...-coasting.html

Hadn't read my SS email from yesterday yet.

ProCoach

You're on the right track...

rm21

Matt - thanks for the post. I took Roger's seminar but we didn't get to do a lot of advanced work on math channels. I'm utilizing many of his examples but there is one type of channel I want to create that has me stumped, which is how to show the Vmin and Vmax values for the turns at a given track. In my case, I'm starting with Road Atlanta. I know how to calculate the distance function, but I'm not sure how to represent the rest of the calculation. In English, it would go something like this: Calculate the minimum GPS speed when the distance is between 500 and 1000 ft. Once I have one working example, I'd be happy to create all the variations and post them. Not sure if this is possible, or if I'm overlooking a simpler way to do this. I know you can get this info in many of the reports, but I want it represented in a math channel so I can quickly compare laps in the channels report.

ProCoach

Matt and Roger may have a way closer to what you want, but a track report is how I would compare.

The way AiM does a distance calculation, it seems like you would have to set the splits to recalculate the start of the next "latching" (peg vMin and vMax for the) sector. So a track report might be your best bet.

Matt Romanowski

It can be done, but takes some work. You are on the right path. You can first get th lap distance with an intergration of laptime to distance, then define the corner distance, then you can take the minimum speed of the corner distance. I'll send you more info later today.