Harry's GPS Suite Forum

Hi,

what´s important for smoothnes of OBD data during overlay (except refresh rate)? I have OBDLink LX. I tried overlay yesterday and it´s really "shi*y".
I know sometimes I need to disconnect phone from BT of the car and keep only OBD and GPS to increase OBD speed rate. But this time it does not helped.

in expert settings I only changed Throttle position to D, everything else is in "standard" settings.

There may be a problem in OBD itself? It use to be OK some time ago, but then I had older FW in OBD adapter.

There is a known problem in sensor fusion resulting in smooth, but stepped movements of OBD data. The problem occurs (at least) in situations with a high rate GPS and a lower rate OBD. E.g. 10 Hz GPS and 8 Hz OBD.

Furthermore, please check if you get consistent OBD readings. It is fine to have ups and downs in update rate by 1 or 2 Hz, but the rate should never drop to 0. The later means there is some problem in communication or connection.

- Harry

Few years ago (approx 4), when I bought OBDLink I had refresh rate about 8Hz and faster, but in last 1-2 years I see rapid fall in refresh rate in HLT (I´m happy if I get over 6Hz). Maybe it depends on firmware on OBD? I can try some older firmwares. Or exclude all unnecessary PIDs?

On track, i had timer view, so I did not check rates on OBD :/ But yes, data are realy "stepped", you can see it in the picture (also on video it´s really annoying)
I tried DashWare and RaceRender and I saw RaceRender have a feature to artifically smooth data. Do you planning something similar in the app?

Hello,

The rate variation is not a real problem as long as it doesn’t drop to zero - which signals a loss of communication. LapTimer applies a quite sophisticated approach to interpolate data correctly independent from varying rates. Or the other way around: rate variation is not the source of anything you will see in overlays. So I assume you run into the first problem I mentioned in my last answer. Do a short manual recording on your way to work using the internal GPS(!) and your LX. Data in gauges should be smooth.

On update rates: LapTimer utilized all known technics to raise OBD rates. You may need to adjust some OBD Tweaks to benefit from this. See the OBD / Engine document available on http://www.gps-laptimer.de/documentation Skipping PIDs is possible, but is not a big lever. There are better ones like parallel requests and ECU filtering.

Harry

Hi Harry,

So I tried it only with internal GPS, and result is the same like before. You can see it in the picture. I checked expert settings. Before I had one custom PID defined (fuel), so I disabled it, without success. Also I make a short screen recording on engine page. Rate flows between 1 to 15Hz.
I double checked everything (I hope so). Also I tried several firmwares. I also disconnected smartwatch, so to the phone only OBD was connected via BT nothing else.

It´s possible there is a problem with data flow from the car?

and here is live video from app
[youtube]https://youtu.be/yUZEySMU1n8[/youtube]

Yes, this is too much... Please create a log as described in the Debugging OBD FAQ here in the forum.

Harry

Ok, I will. Thanks Harry.

But. I tried OBDLink app, and I also noticed same problems there. If I look on revs and I try to slowly raise them, gauge is not smooth just like in HLT. So I think problem will be somewhere else :/ Unfortunately I don´t have access to any other car than VW brand (SEAT and Skoda) to try it on different car.

Do the log please, maybe we can see something we can work around.

Harry

Hi Harry, I did a log, you should have it in your mail