GEAR number drops to 0

[KAZUNA]

GEAR number calculation looks good however, GEAR number drops to 0 for just a few samples, especially when the gear changes.
As you can see my LapTimerGPSRecDB.csv is attached, you can find GEAR number dropping to 0.

If I understand correctly, GEAR number is calculated based on the RPM, SPEED, and GEAR ratio but all other OBD data looks fine.

Any idea what's causing this?
Any way to fix or workaround it?

# drops to 0 while staying at 3rd
143886 3
143887 0
143888 3

# drops to 0 when changing from 3rd to 2nd
144024 3
144025 0
144026 2

# drops to 0 for three samples when changing from 3rd to 2nd
144723 3
144724 0
144725 0
144726 0
144727 2

# drops to 0 for five samples when changing from 3rd to 4th
144847 3
144848 0
144849 0
144850 0
144851 0
144852 0
144853 4

[Harry]

That's easy. While shifting gear / engaging the clutch, there is no defined relation between rpm, speed and gear.

[KAZUNA]

It's DCT and there is virtually no engaging gap between gears.
My understanding is that this GEAR number is not coming from OBD but HLT calculates it from the RPM, SPEED and GEAR ratio, correct?

[Harry]

Yes, it is calculated. Make sure your gear and drive ratios are set correctly in vehicle details.

[KAZUNA]

Yes, gear and drive ratios are set correctly.
As you can see in the csv attached, look at GEAR 0 value, RPM and SPEED look fine but HLT gets GEAR 0.
How come HLT is getting GEAR 0 from those OBD data?

[Harry]

LapTimer selects 0 in case no valid match between speed measured and speed resulting from any gear/drive/wheel/rpm combination is found. So in case you get 0, either gear/drive or wheel parameters for your vehicle definition is wrong, or speed measured is wrong.

[KAZUNA]

Maybe it is because DCT and due to the automatic rev-matching or something, the parameters may look a little out of range to HLT?
That's probably why this is happening during the gear shifting in most cases?

I guess if HLT can hold the previous gear number for a bit instead of selecting 0 in case it was just for a second or two, it would look more natural.

[Harry]

I guess you want to post your gear and drive ratios as well as drive type plus wheel sizes plus the precise car specification. There is a threshold of 10km/h difference to find the best gear match, that should be more than enough.

[KAZUNA]

Is this information enough to give you an idea?

Drive Ratio: 3.58

Gear 1 Ratio: 3.84
Gear 2 Ratio: 2.43
Gear 3 Ratio: 1.78
Gear 4 Ratio: 1.43
Gear 5 Ratio: 1.21
Gear 6 Ratio: 1.04
Gear 7 Ratio: 0.88
Gear 8 Ratio: 0.75
Gear 9 Ratio: 0.63

Drive Type: All-wheel

Front Wheel: 245/35 19
Rear Wheel: 305/30 20

Max RPM: 7500 rpm

[Harry]

Which car / model / year / style?