System (GPS) user in Great Britain, using the free services
provided , can obtain precise coordinates in the European standard
GPS coordinate system ETRS89, and instantly convert these to
British National Grid and heights above mean sea level (Newlyn
datum) using Ordnance Survey national standard high-precision
transformation models. Surveyors and GIS developers can convert
2D and 3D spatial datasets from GPS coordinates to Ordnance
Survey coordinates and vice-versa, with high accuracy.
Viva GS12 Smartrover and has experienced surveyors
who have beeb using the technology for many
years. We are therefore able
to integrate its use into your project large or small at a cost
that is realistic and economic.
(European Terrestrial Reference System 1989)
is our national coordinate system for 3D GPS positioning. It
is a much more exacting definition of the GPS coordinate system
than the better known WGS84 standard. Consequently, ETRS89
coordinates are also WGS84 coordinates, but be aware that
general WGS84 coordinates do not necessarily meet the ETRS89
standard. ETRS89 is the GPS coordinate system standard used
for high-quality GPS surveys throughout Europe.
(Ordnance Survey Great Britain 1936)
is our national coordinate system for topographic mapping. It
is used for Ordnance Survey mapping at all scales, and for many
private topographic surveys.
The OSGB36 part of the name refers to the geodetic datum (system
of latitude and longitude) used, and the National Grid part
refers to the map projection and grid referencing convention
for eastings and northings.
(Ordnance Datum Newlyn)
is our national coordinate system for heights above mean sea
level (orthometric heights). It was originally based on
tide gauge readings at Newlyn, Cornwall. ODN is the usual
definition of height above mean sea level in mainland Britain
and some islands.
Survey has fully adopted GPS positioning
as the basis of all three national coordinate systems listed
above. So in the future, OSGB36 National Grid will not
be realised by triangulation stations, and ODN will not be realised
by levelled bench marks - both will be realised by GPS positioning. All
surveyors who want to take advantage of the new infrastructure
will therefore need access to survey-grade GPS equipment.