[Talk-transit] NaPTAN bus stop database import - some more observations

[Peter J Stoner]

In message <ab4a6cf40904010541h22865786v247b90346238853d at mail.gmail.co 
m>
          Brian Prangle <bprangle at googlemail.com> wrote:

> Some more views and observations  on the NaPTAN data import in Birmingham:

> 1.       It serves as a great QA on OSM data and shows that in the City
> Centre where we have not been able to get decent GPS traces more accuracy is
> needed so the potential of obtaining aerial photography is great.

> 2.        It’s a great impetus to resurvey streets where earlier work
> (potentially inaccurate from NPE tracing, older GPS devices, less points
> collected,  inexperience, not realising that roads have a width greater than
> the rendered line so placing bus stops too close to the road etc.) can be
> improved.


I was in Birmingham today and obtained a trace on the top deck of a 
number 16 bus as it did its loop around the city centre.  There are 
now two traces down Corporation Street.  The more eratic one is me 
walking down the pavement.  Both traces are quite close to the NaPTAN 
stops.

Is there a reason for there not being more traces in Central 
Birmingham?

My trace suggests that the NaPTAN points in Lower Bull Street are 
probably too far from the road but conversely the OSM stops are in the 
middle of the road.  The true position may be in between.

The discrepancy between my trace and Station Street is very marked.  
Is the turn from Hill Street into Station Street a right angle as in 
OSM or less sharp?   The NaPTAN points are closer to my trace.




-- 
Peter J Stoner
UK Regional Coordinator
Traveline                       www.travelinedata.org.uk

a trading name of
Intelligent Travel Solutions Ltd  company number 3826797
Drury House, 34-43 Russell Street, LONDON WC2B 5HA