Re: [RPI Map Dev] RPI Map List

[Jie B. <ba...@cs...>]

Thanks Brian. 5 seconds updating is certainly much better. I just
googled a little and find there are a couple GPS tracking systems can
do this. I hope our GPS vendor also supports it.

An alternative for "realtime" position maybe using the route and
shuttle speed information to predict the location of the bus before
the next position report. We may show both the known position and
predict of a bus, using different icons. I'm also thinking about using
different icons for each shuttle, so the predicted bus locations can
be distinguished.

Jie

On Thu, Jan 29, 2009 at 6:19 PM, Brian Michalski <mi...@rp...> wrote:
> Hi Jie,
> I'm glad to hear the database access is working out well for you.
> The vendor the original shuttle tracking group chose a 2-3  years ago to
> supply the GPS tracking units specialized in fleet management, providing
> tools for companies to see where their fleet of vehicles are and where they
> have historically been.  Unfortunately the vendor is very concerned about
> load on their servers, and for us to be able to use the API that lets us see
> where the shuttles are, we had to agree to limit our requests to around one
> every 15 seconds.  Additionally, the units in the bus only update their
> position every time they travel 1/4 of a mile.  This accurate enough for a
> tracking a nationwide fleet of big rigs but for our smaller scale operation
> the update interval is a little constricting.
> We're in the process of upgrading a few things on our end behind the scenes,
> and I hope that will resolve any delayed update issues we might be
> experiencing.  I'm going to try to have the server update the database at a
> random interval between 10 and 15 seconds past the previous update, and the
> new structure we're working on should ensure we're updating the database in
> very consistent fashion.
> I might try to put a call into our GPS vendor to see if they can do
> something on their end to pull the data any faster.  If they say its OK for
> us to get an update from them every 5 seconds, I'd be more than happy to
> update our interval accordingly.
> Hopefully this helps,
> Brian Michalski
>
> On Thu, Jan 29, 2009 at 3:34 PM, Jie Bao <ba...@cs...> wrote:
>>
>> Hi Brian & Brian
>>
>> We have got bus updated every second on RPI Map, by directly visiting
>> your database. Thanks a lot for sharing the DB access with us! The
>> following credit line is added on the main page
>>
>> "Bus position, route and stops are provided by the
>> [http://shuttles.rpi.edu RPI Shuttle Tracking] site."
>>
>> Even the code allow by-second updating, apparently the data is updated
>> much less frequently. My observation is that bus locations change in
>> about every 20 seconds.
>>
>> There are a couple of other campus shuttle tracking systems that
>> enable second-by-second tracking. For example:
>> http://umbc.transloc.com/
>>
>> Will the RPI shuttle GPS reporting device be able to update more
>> frequently? It will give more real-timeness if the shuttle icon can
>> move constantly.
>>
>> Jie
>>
>> On Thu, Jan 29, 2009 at 12:40 PM, Jie Bao <ba...@cs...> wrote:
>> >
>> > https://lists.sourceforge.net/lists/listinfo/semanticmap-rpimap
>> >
>> > We will use this list for RPI Map
>> >
>> > --
>> > Jie
>> > http://www.cs.rpi.edu/~baojie
>>
>>
>>
>> --
>> Jie
>> http://www.cs.rpi.edu/~baojie
>
>



-- 
Jie
http://www.cs.rpi.edu/~baojie