Harry's GPS Suite Forum

I am getting ready for an OTD on Sunday and am working on my telemetry collection now. I am noticing after some updates to HLT that my sensor delays aren't the same as I set them.

Prior to v18 (I think it was still V17) I had a 0.4s sensor delay on "Any OBD" the Dual XGPS (5Hz) at 1.5s with Int. Accel at 0.5s. I think "Any OBD" was the only one different from default. Anyway, after the updates "Any OBD" is now back at default (1s IIRC), and I am wondering if I should change it to 0.4s since that produced the best timing results from previous testing I've done. I would go out and test more, but my new track day car isn't insured/registered so I like to minimize running it on the street. Unfortunately, that leaves waiting until after the OTD and finding out the hard way.

I guess my question is; did anything regarding sensor delays change in the software from late '13 to now that would require a different sensor delay setting or should I be good setting to the previous value I was using?

Hi,

There is no change in delay handling although OBD delays have been mapped to one value from several some versions ago. OBD delays mostly on the car and update rates achieved. The default is good for around 4 Hz, reduce it if you get more.

Harry

Harry wrote:Hi,

There is no change in delay handling although OBD delays have been mapped to one value from several some versions ago. OBD delays mostly on the car and update rates achieved. The default is good for around 4 Hz, reduce it if you get more.

Harry

OK, so you're saying the delay setting has more to do with the vehicle's OBD data rate than other factors (HLT changes, iOS device, etc). If that is the case I should be fine with 0.4s, since it's basically (not identically) the same car. Is there anything I can monitor live to help confirm they are matched? Watch RPMs live on HLT versus tachometer perhaps? When testing it previously I created a test course around my block and then would make sure my test run movements matched on the accelerometers, GPS, and OBD output. I would have to go back on the PC and import everything into Dashware to make sure it all aligned. If I could do it live and make appropriate adjustments real time it may help.

I haven't been on the track since this happened (http://youtu.be/lvlMr24_jB8). That was essentially a year ago; so I think HLT has had a few updates since then. Wasn't sure if one of them altered how the delay mechanism worked.

As a general rule, sensor delays rarely need adjustments to generate nice overlaid videos. The only sensor related mismatch you will see immediately are problems with acceleration and OBD. The delay that is more often changed is the relation between data recordings and video. This is something you will see immediately and needs more fine tuning. As long as you use Dashware (and align data and video manually anyway), you do not need to change this either. But to answer your questions: create a short recording around the block and watch the relation between throttle and longitudinal acceleration. In case this looks fine, the rest will be fine too (mostly ).

- Harry