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Re: [HOWTO] Debugging OBD Communication

Posted: Mon Mar 09, 2015 5:44 pm
by froggy47
gplracerx wrote:I set my accelerometer update rate to 100Hz. It shows up as 91Hz on the accelerometer display. At 20Hz, the filter time constant is too low for autocross, in my opinion. YMMV. If I get time, I'll put up some graphs to show the effect. I've got to prep the car for the Dixie National Tour event this weekend.
I would really like to see those, thanks you if you can post.

:)

Re: [HOWTO] Debugging OBD Communication

Posted: Mon Mar 09, 2015 5:47 pm
by froggy47
Is there any downside to going higher than 30 Hz?

:)

Re: [HOWTO] Debugging OBD Communication

Posted: Mon Mar 09, 2015 6:09 pm
by Harry
Yes, processing load / battery drain. 30 Hz is good for GPS update rates of 10 Hz and below. Some prefer higher resolution to get less smoothing, but for most, 30 Hz is fine.

- Harry

Re: [HOWTO] Debugging OBD Communication

Posted: Mon Mar 09, 2015 8:53 pm
by froggy47
Harry wrote:Yes, processing load / battery drain. 30 Hz is good for GPS update rates of 10 Hz and below. Some prefer higher resolution to get less smoothing, but for most, 30 Hz is fine.

- Harry
Thanks Harry!

I just realized there are (in expert settings):

Accelerator tweaks update rate (mine is now 30)

AND

Sensor Delays (also in expert settings):

GPS 1.5
OBD 1.0
Accelerator 0.5

Those I believe are the default sensor delays, are they OK?

:)

Re: [HOWTO] Debugging OBD Communication

Posted: Mon Mar 09, 2015 9:16 pm
by Harry
Yes, these are the default. Please don't change them. Video Synchronization / Video should be 1.0.

- Harry

P.S. None of these are related to OBD communication.

Re: [HOWTO] Debugging OBD Communication

Posted: Tue Mar 10, 2015 4:20 am
by froggy47
Harry wrote:Yes, these are the default. Please don't change them. Video Synchronization / Video should be 1.0.

- Harry

P.S. None of these are related to OBD communication.

Overlay Synchronization

Video 0.0-9.0s
This preference's current value: "0.5"

I HAVE NEVER TOUCHED THIS.

:)

Re: [HOWTO] Debugging OBD Communication

Posted: Tue Mar 10, 2015 8:06 am
by Harry
Yes, sure :-D

Re: [HOWTO] Debugging OBD Communication

Posted: Tue Mar 10, 2015 3:58 pm
by gplracerx
30Hz is fine for track use. In autocross, the time constants for direction changes are much shorter than on a race track and need a correspondingly smaller time constant filter. The filter time constant is proportional to the sampling time constant. A higher sampling rate gives a smaller time constant.

Re: [HOWTO] Debugging OBD Communication

Posted: Tue Mar 10, 2015 5:36 pm
by froggy47
gplracerx wrote:30Hz is fine for track use. In autocross, the time constants for direction changes are much shorter than on a race track and need a correspondingly smaller time constant filter. The filter time constant is proportional to the sampling time constant. A higher sampling rate gives a smaller time constant.
Trying 100.

:)

Re: [HOWTO] Debugging OBD Communication

Posted: Tue Mar 10, 2015 5:38 pm
by froggy47
Harry wrote:Yes, sure :-D
Haha, really I never touched it, should it be 1.0? I don't even know what it does.

:)