10hz GPS + GoPoint BT1A gives noisy OBD data

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fredemmott
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10hz GPS + GoPoint BT1A gives noisy OBD data

Post by fredemmott »

When using the built-in GPS data, I was getting perfectly smooth OBD data in the videos. I'm now seeing rapidly fluctuating data that doesn't seem right, both in the videos and in the data files.

Raw data: https://dl.dropboxusercontent.com/u/237 ... 404.hlptrl

As a workaround, I'm using https://gist.github.com/fredemmott/861f800299f694eaefb6 to make 1hz versions of the CSV file, and putting both the full version and 1hz version into RaceRender - and switching the noisy displays to use the 1hz version

I'm using a BT1 and an XGPS160
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Harry
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Re: 10hz GPS + GoPoint BT1A gives noisy OBD data

Post by Harry »

Using the internal GPS means that only a tens of the load needs to be processed. OBD is pretty sensible to system overloads and usually the first item that breaks. Which smartphone do you use?

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fredemmott
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Re: 10hz GPS + GoPoint BT1A gives noisy OBD data

Post by fredemmott »

iPhone 6 - and I'm not recording video on it so there's no encoding contributing to the load.
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Harry
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Re: 10hz GPS + GoPoint BT1A gives noisy OBD data

Post by Harry »

The 6 should be quick enough :-) Have you checked for other - disturbing BT devices? What exactly is OBD showing? Is the connection dropping or is the update rate going up and down (a lot)?

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