Jargo.v2

Great news came in on Friday - Shawn plotted points.

We picked some random PID's to have a look at. It was great seeing points come up for the first time



Although we noticed a small problem - it would skip certain points and not be a uniform representation of the data.

So I investigated that yesterday. I first of all looked at the raw data and the speed at which he travelled to make sure he didnt suddenly stop.



The graph is his speed over a period of 40 minutes. [time starts on the right].

we can see that in the period that i show above - his fluctuation in speed cannot be responsible for missing data.

so i had a further look at the data, and saw quite an immense discrepency between the time points were added to the server, and the UTC time recorded on the devices. i expected a direct corrilation between the two. Yet what I got was a fluctuation of between -3 and up to 20 seconds.

then there were no points for several seconds and some times up to 10 seconds, which would account for missing data points.

So I put the missing points to two possible variables.

1. Woop Woop - places that Shawn drives around - usually have not the best GPRS reception. So that is a very feasible problem cause and would explain the missing points.

2. Software that I wrote for the phone doesnt sync. properly the baud rate of the GPS device.

So today I re-designed it from the ground up today in order to be more precise and hopefully sync properly.

Astoundingly - it[software - aka Jargo {stands for GPS Aggregator}] now reports accuracy up to 1 thousandth of a second. Only way to check that though - is to load it up onto our test phone [which Shawn has been carrying around] and give it a whirl. No matter how accurate it is though, will still have to account for the delay in communications.