Sequential gear shift control issue

[SimonR32]

I have a R32 GTR with Albins sequential, set up with a G4X and using a gear lever force to start cut and gear barrel position sensor to end the cut. Everything seems to working very well in logs for all gears apart from the 4th to 5th shift where the ECU is introducing torque too early and seemingly ignoring its settings.

Basic settings for the barrel are 0-5V analog sensor, voltage tolerance of 0.26V and next gear reached voltage margin is 0.15V.

4th gear is 0.34V and 5th gear is 4.5V

When under power in 4th gear is around 0.34V, when the shifter is pulled this drops to around 0.2V, before the gear starts to change and it shoots up to 4.5V. By the software logic, the driven upshift should cease and the torque introduction should engage when the voltage is 4.5V +/- 0.15, in this case therefore at 4.35V

But for some reason, it's engaging the torque introduction much earlier, see example below

It actually appears to be using the minimum shift time (which is set to 30ms) rather than waiting for the waiting for the next gear voltage margin window. 

It only has the issue in 4th to 5th, which coincidentally and I'm unsure if related is the only gear that when upshifted goes from a lower voltage to a higher voltage.

It also frustratingly doesn't appear to always happen. Example below when it appears to work fine.

No issues in any of the other gears... Help?!?

 

 

[Electredge]

have you done other sequential setups where the barrel sensor rotated back around to a higher volatge? I'm not sure if thats causing your issue but seems likely. does your vehicle speed work? and have you setup the gear ratio table in the ecu?

can you post up a log and copy of the map?

[Adamw]

You will need to log gear pos voltage at 500Hz minimum to see enough detail.  It is not going to work correctly with a gear position voltage that rolls past 0V and back to 5V during a normal shift.  It is ok for that to happen during an R or N shift but not for a normal shift.  Your voltage doesnt reflect barrel rotation so the "next gear voltage margin wont be applied incorrectly.  If we plotted gear pos voltage (Y axis) Vs gear barrel rotation yours would look something like below.  

So the correct shift end would be 0.15V before 5th which is 4.65V where I have put the green dot.  But because the ecu only knows 4th is 0.34V and 5th is 4.5V, it will use 4.5-0.15 = 4.35V as the shift end (where I have the red dot), which is only about halfway through the shift.  Notice also 4.65V would occur just above the red dot as well so even if you fudged the voltages somehow the shift end would still occur in the wrong place.  

[SimonR32]

Thanks for the quick reply.

 

So essentially do a physical clock of the sensor so all line up in a sequential voltage drop?

 

Ps. I believe that AN4 was logging at 1000hz

[Electredge]

4 minutes ago, SimonR32 said:

Thanks for the quick reply.

 

So essentially do a physical clock of the sensor so all line up in a sequential voltage drop?

 

Ps. I believe that AN4 was logging at 1000hz

yes physically re-clock the sensor so that 1-6 are all ascending/descending voltage changes, as Adam said above reverse and neutral can rotate off the linear scale but not the drive gears.